5 CCR 1002-32
DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT Water Quality Control Commission REGULATION NO. 32 CLASSIFICATIONS AND NUMERIC STANDARDS FOR ARKANSAS RIVER BASIN 5 CCR 1002-32 [Editor’s Notes follow the text of the rules at the end of this CCR Document.]
32.1 AUTHORITY [Eff. 12/31/2007]
These regulations are promulgated pursuant to section 25-8-101 et seq. C.R.S., as amended, and in particular, 25-8-203 and 25-8-204.
32.2 PURPOSE [Eff. 12/31/2007]
These regulations establish classifications and numeric standards for the Arkansas River, including all tributaries and standing bodies of water as indicated in section 32.6. The classifications identify the actual beneficial uses of the water. The numeric standards are assigned to determine the allowable concentrations of various parameters. Discharge permits will be issued by the Water Quality Control Division to comply with basic, narrative, and numeric standards and control regulations so that all discharges to waters of the state protect the classified uses. (See Regulation No. 31, section 31.14). It is intended that these and all other stream classifications and numeric standards be used in conjunction with and be an integral part of Regulation No. 31 Basic Standards and Methodologies for Surface Water.
32.3 INTRODUCTION [Eff. 12/31/2007]
These regulations and tables present the classifications and numeric standards assigned to stream segments listed in the attached tables (See section 32.7). As additional stream segments are classified and numeric standards for designated parameters are assigned for this drainage system, they will be added to or replace the numeric standards in the tables in section 32.7. Any additions or revisions of classifications or numeric standards can be accomplished only after public hearing by the Commission and proper consideration of evidence and testimony as specified by the statute and the “Basic Standards and Methodologies for Surface Water” .
32.4 DEFINITIONS [Eff. 12/31/2007]
See the Colorado Water Quality Control Act and the codified water quality regulations for definitions.
32.5 BASIC STANDARDS [Eff. 12/31/2007]
(1) TEMPERATURE All waters of the Arkansas River Basin are subject to the following standard for temperature. (Discharges regulated by permits, which are within the permit limitations, shall not be subject to enforcement proceedings under this standard). Temperature shall maintain a normal pattern of diurnal and seasonal fluctuations with no abrupt changes and shall have no increase in temperature of a magnitude, rate, and duration deemed deleterious to the resident aquatic life. This standard shall not be interpreted or applied in a manner inconsistent with section 25-8-104, C.R.S. Effective until December 31, 2012: Segments or portions of segments that are first, second or third order streams above 7000 feet elevation and classified Aquatic Life cold 1 or 2 shall have a chronic temperature standard of 17 °C (MWAT) with no acute standard. Other cold class 1 or 2 segments or portions of segments shall have a chronic temperature standard of 20 °C (MWAT) with no acute standard. Segments that are classified Aquatic Life warm 1 or 2 shall have a chronic temperature standard of 30 °C (MWAT) with no acute standard.
(2) QUALIFIERS See Basic Standards and Methodologies for Surface Water for a listing of organic standards at
(3) URANIUM
32.6 TABLES [Eff. 12/31/2007]
(1) Introduction The numeric standards for various parameters in the attached tables were assigned by the Commission after a careful analysis of the data presented on actual stream conditions and on actual and potential water uses.
(2) Abbreviations:
Ag = silver Al = aluminum As = arsenic B = boron Ba = barium Be = beryllium Cd = cadmium ch = chronic (30-day)
Cl = chloride Cl 2 = residual chlorine CN = free cyanide CrIII = trivalent chromium CrVI = hexavalent chromium Cu = copper dis = dissolved D.O. = dissolved oxygen E. coli = escherichia coli F = fluoride Fe = iron Hg = mercury mg/l = milligrams per liter ml = milliliters Mn = manganese NH 3 = ammonia as N(nitrogen)
Ni = nickel NO 2 = nitrite as N (nitrogen)
NO 3 = nitrate as N (nitrogen)
OW = outstanding waters P = phosphorus Pb = lead S = sulfide as undissociated H 2 S (hydrogen sulfide)
Sb = antimony Se = selenium SO 4 = sulfate sp = spawning Tl = thallium tr = trout Trec = total recoverable TVS = table value standard U = uranium µg/l = micrograms per liter UP = use-protected Zn = zinc
Fe(ch) = WS(dis)
Mn(ch) = WS(dis)
SO 4 = WS These abbreviations mean: For all surface waters with an actual water supply use, the less restrictive of the following two options shall apply as numerical standards, as specified in the Basic Standards and Methodologies at 31.16 Table II and III:
(3) Table Value Standards In certain instances in the attached tables, the designation “TVS” is used to indicate that for a particular parameter a “table value standard” has been adopted. This designation refers to numerical criteria set forth in the Basic Standards and Methodologies for Surface Water. The criteria for which the TVS are applicable are on the following table.
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32.7 – 32.9 RESERVED
32.10 STATEMENT OF BASIS AND PURPOSE
I. Introduction These stream classifications and water quality standards for State Waters of the Arkansas River Basin including all tributaries and standing bodies of water in all or parts of Lake, Chaffee, Custer, Fremont, El Paso, Pueblo, Huerfano, Las Animas, Otero, Bent, Prowers, Baca, Kiowa, Cheyenne, Lincoln, Teller, and Elbert Counties implement requirements of the Colorado Water Quality Control Act of 1981, C.R.S. 1973, 25-8-101 et seq . (Cum. Supp. 1980). They also represent the implementation of the Commission's Regulations Establishing Basic Standards and an Antidegradation Standard and Establishing a System for Classifying State Waters, for Assigning Standards, and for Granting Temporary Modifications (the “Basic Regulations” ) The Basic Regulations establish a system for the classification of State Waters according to the beneficial uses for which they are suitable or are to become suitable, and for assigning specific numerical water quality standards according to such classifications. Because these stream classifications and standards implement the Basic Regulations, the statement of basis and purpose (Section 3.1.16) of those regulations must be referred to for a complete understanding of the basis and purpose of the regulations adopted herein. Therefore, that statement in the Basic Regulations is incorporated by reference. The focus of this statement of basis and purpose is on the scientific and technological rationale for the specific classifications and standards in the Arkansas River Basin.
II. General Considerations 1. These regulations are not adopted as control regulations. Stream classifications and water quality standards are specifically distinguished from control regulations in the Water Quality Control Act, and they need not be adopted as control regulations pursuant to the statutory scheme.
2. The Commission has been requested in public hearings to rule on the applicability of these and other regulations to the operation of water diversion facilities, dams, transport systems, and the consequent withdrawal, impoundment, non-release and release of water for the exercise of water rights. The Commission has determined that any such broad ruling is inappropriate in the context of the present regulations. The request does not raise specific questions as to proposed classifications and standards. However, the Commission has taken into account the fact that some issues are unresolved in adopting classifications and standards. On January 5, 1981, the Commission adopted a policy statement on quality/quantity issues that addresses a number of these concerns. Finally, the Commission has adopted these regulations in compliance with the requirements of the Water Quality Control Act as amended by S.B.10 in 1981 that have bearing on these issues (See e.g.) sections 102, 104, and 503(5).
III. Definition of Stream Segments 1. For purposes of adopting classifications and water quality standards, the streams and water bodies are identified according to river basin and specific water segments.
2. Within each river basin, specific water segments are defined, for which use classifications and numeric water quality standards are adopted. These segments may constitute a specified stretch of a river mainstem, a specific tributary, a specific lake or reservoir, or a generally defined grouping of waters within the basin (e.g., a specific mainstem segment and all tributaries flowing into that mainstem segment).
3. Segments are generally defined according to the points at which the use, water quality, or other stream characteristics change significantly enough to require a change in use classification and/or water quality standards. In many cases, such transition points can be specifically identified from available data. In other cases the delineation of segments is based upon best judgments of the points where instream changes in uses, water quality, or other stream characteristics occur.
IV. Use Classifications — Generally 1. The use classifications have been established in accordance with the provisions of Section 203 of the Water Quality Control Act and Section 3.1.6 and 3.1.13 of the Basic Regulations. Each classification is based upon actual current uses or existing water quality. In the latter case, even though the use may not be in place, the classification is attached if existing water quality would allow that use, and if the use may be reasonably expected in the future.
2. In all cases the basic regulation has been followed, in that an upstream use cannot threaten or degrade a downstream use. Accordingly, upstream segments of a stream are generally the same as, or higher in classification than, downstream segments. In a few cases, tributaries are classified at lower classifications than mainstems, where flow from tributaries does not threaten the quality of mainstem waters and where the evidence indicates that lower classifications for the tributaries is appropriate.
3. There have been no “High Quality Class 1” designations assigned in this basin.
4. The Commission has determined that it has the authority to assign the classification “High Quality Waters - Class 1” and High Quality Waters - Class 2” where the evidence indicates that the requirements of Sections 3.1.13(1)(e) of the basic regulations are met. The validity of this classification has been determined on a case-by-case basis. The classification “High Quality Waters - Class 2” has been assigned where these waters met the provisions of Section 3.1.13(e)
5. Qualifiers — “Goal”
6. Recreation — Class 1 and Class 2 In addition to the significant distinction between Recreation - Class 1 and Recreation -Class 2 as defined in Section 3.1.13(1) of the Basic Regulations, the difference between the two classifications in terms of water quality standards is the fecal coliform parameter. Recreation - Class 1 generally has a standard of 200 fecal coliform per 100 ml; Recreation - Class 2 generally has a standard of 2000 fecal coliform per 100 ml.
7. Water Supply Classification The Commission finds that Colorado is a water short state and that it is experiencing considerable growth which places additional burdens on already scarce water supplies. These considerations mitigate in favor of a conservative approach to protecting future water supplies. Where existing water quality is adequate to protect this use, and in the absence of dischargers to these segments, or testimony in opposition to such classification, the water supply use has been assigned because it is reasonable to expect that it may exist in the future in such cases. For stream segments that flow through, or in the vicinity of, municipalities, this conclusion is further justified, since there is a reasonable probability that the use exists or will exist. Where the water supply classification has been opposed, the Commission has evaluated the evidence on a site specific basis, and in many cases the classification has been removed.
V. Water Quality Standards — Generally 1. The water quality standards for classified stream segments are defined as numeric values for specific water quality parameters. These numeric standards are adopted as the limits for chemical constituents and other parameters necessary to protect adequately the classified uses in all stream segments.
2. Not all of the parameters listed in the “Tables” appended to the Basic Regulations are assigned as water quality standards. This complies with Section 3.1.7(c) of the Basic Regulations. Numeric standards have been assigned for the full range of parameters to a number of segments where little or no data existed specific to the segment. In these cases, there was reason to believe that the classified uses were in place or could be reasonably expected, and that the ambient water quality was as good as or better than the numeric standards assigned.
3. A numeric standard for the temperature parameter has been adopted as a basic standard applicable to all waters of the region in the same manner as the basic standards in Section 3.1.11 of the Basic Regulations.
4. Numeric standards for nineteen organic parameters have been adopted as basic standards applicable to all waters of the region in the same manner as the basic standards in Section 3.1.11 of the Basic Regulations. These standards are essential to a program designed to protect the waters of the State regardless of specific use classifications because they describe the fundamental conditions that all waters must meet to be suitable for any use. It is the decision of the Commission to adopt these standards as basic standards because the presence of the organic parameters is not generally suspected. Also, the values assigned for these standards are not detectable using routine methodology and there is some concern regarding the potential for monitoring requirements if the standards are placed on specific streams. This concern should be alleviated by Section 3.1.14(5) of the Basic Regulations but there is uncertainty regarding the interpretation of those numbers by other entities. Regardless of these concerns, because these constituents are highly toxic, there is a need for regulating their presence in State waters. Because the Commission has determined that they have uniform applicability here, their inclusion as basic standards for the region accomplishes this purpose.
5. In many cases, the numeric water quality standards are taken from the “Tables” appended to the Basic Regulations. These table values are used where actual ambient water quality data in a segment indicates that the existing quality is substantially equivalent to, or better than, the corresponding table values. This has been done because the table values are adequate to protect the classified uses.
6. In many cases, instream ambient water quality provides the basis for the water quality standards (See 7 below). In those cases where the classified uses presently exist or have a reasonable potential to exist despite the fact that instream data reflects ambient conditions of lower water quality than the table values, instream values have been used. In these cases, the evidence indicates that instream values are adequate to protect the uses. In those cases where temporary modifications are appropriate, instream values are generally reflected in the temporary modification and table values are reflected in the corresponding water quality standard. (Goals are established for the appropriate classification affected by the parameter). Cases in which water quality standards reflect these instream values usually involve the metal parameters. On many stream segments elevated levels of metals are present due to natural or unknown causes, as well as mine seepage from inactive or abandoned mines. These sources are difficult to identify and impractical or impossible to control. The classified aquatic life uses may be impacted and/or may have adjusted to the condition. In either case, the water quality standards are deemed sufficient to protect the uses that are present.
7. In most cases in establishing standards based on instream ambient water quality, a calculation is made based upon the mean (average) plus one standard deviation (x + s) for all sampling points on a particular stream segment. Since a standard deviation is not added to the water quality standard for purposes of determining the compliance with the standard, this is a fair method as applied to discharge.
A number of different statistical methodologies could have been used where ambient water quality data dictates the standards. All of them have both advantages and disadvantages. It is recognized that the x + s methodology also has weaknesses, in that the standard may not reflect natural conditions in a stream 100 per cent of the time, even though the use of x + s already allows for some seasonal variability. However the use of this methodology is nevertheless justified since it provides the most meaningful index of stream quality of all methodologies proposed for setting stream standards. Just as the Commission has not established standards that reflect the best water quality that may ever occur in a stream, so too it has rejected methodologies that would establish standards that reflect the worst water quality that may ever occur. The establishment of standards on any basis is more lenient than x + s would not provide adequate protection for the classified uses.
Finally, the fairness and consistency of the use of any methodology in setting standards must turn on the manner in which the standards are implemented and enforced. It is essential that there be consistency between standard setting and the manner in which attainment or non-attainment of the standards is established based on future stream monitoring data. In addition the Division must take this methodology into account in writing and enforcing discharge permits.
8. No water quality standards are set below detectable limits for any parameter, although certain parameters may not be detectable at the limit of the standards using routine methodology. However, it must be noted that stream monitoring as opposed to effluent monitoring, is generally not the responsibility of the dischargers but of the State. Furthermore, the purpose of the standards is to protect the classified uses and some inconvenience and expense as to monitoring is therefore justifiable.
9. The dissolved oxygen standard is intended to apply to the epilimnion and metalimnion strata of lakes and reservoirs. Respiration by aerobic micro-organisms as organic matter is consumed is the primary cause of a natural decrease in dissolved oxygen and anaerobic conditions in the hypolimnion. Therefore, this stratum is exempt from the dissolved oxygen standard.
10. When numeric standards are established based on historic instream water quality data at the level of x + s, it is recognized by the Commission that measured instream parameter levels might exceed the standard approximately 15 percent of the time.
11. It is the Commission's intention that the Division implement and enforce these water quality standards consistent with the manner in which they have been established.
12. Hardness/Alkalinity Where hardness and alkalinity numbers differed, the Commission elected to use alkalinity as the controlling parameter, in order to be consistent with other river basins and because testimony from the Division staff indicated that in most cases alkalinity has a greater effect on toxic form of metals than does hardness.
VI. Water Quality Standards for Unionized Ammonia For warm water class 2 segments having an ammonia standard greater than 0.06 mg/l the basis for higher than criteria value is that these streams generally contain both lesser numbers and types of species than those inhabiting class 1 streams due to physical habitat characteristics, flow or irreversible water quality characteristics. The Commission felt that the incremental expense to meet a 0.06 mg/l unionized ammonia standard for present or potential discharges along these streams cannot be justified. Flow in these segments is often intermittent or highly impacted by diversions.
Not all warmwater streams are comparable in terms of flow habitat, and types and numbers of species of aquatic life. Therefore, some variations in an appropriate ammonia standard must be tolerated, with the objective of protecting existing aquatic life. The Commission found this approach preferable to totally removing the aquatic life classification from impacted or marginal aquatic life streams.
VII. Water Quality Standards for Uranium Given the threat that radioactivity from uranium may pose to human health, it is advisable to limit uranium concentrations in streams to the maximum extend practicable. The Commission finds that based on the record of these hearings a uranium standard is particularly necessary to protect the water supply classification. In the face of significant controversy and conflicting testimony, the Commission has adopted a standard of 40 pCi/l or natural background where higher, for the following reasons:
VIII. Water Quality Standards for Cyanide The Commission acknowledges that total cyanide is to be used in State Discharge permits until a method is authorized by EPA for measuring free cyanide, even though free cyanide is the parameter of concern. While cyanide has received special treatment in cases discussed in the segment - by - segment section which follows, a free cyanide standard based on Table Values has been established for most segments.
IX. Linkage of classifications and Standards The Commission holds that the classifications which it adopts and the standards it assigns to them are linked. Disapproval by EPA of the standards may require reexamination by the Commission of the appropriateness of its original classification. The reason for the linkage is that the Commission recognizes that there is a wide variability in the types of aquatic life in Colorado streams which require different levels of protection. Therefore, the numbers were chosen in some cases on a site specific basis to protect the species existing in that segment. If such a reclassification is deemed a downgrading, then it will be based upon the grounds that the original classification was in error.
X. Economic Reasonableness The Commission finds that these use classifications and water quality standards are economically reasonable. The Commission solicited and considered evidence of the economic impacts of these regulations. This evaluation necessarily involved a case-by-case consideration of such impacts, and reference is made to the fiscal impact statement for this analysis. Generally, a judgment was made as to whether the benefits in terms of improving water quality justified the costs of increased treatment. In the absence of evidence on economic impacts for a specific segment, the Commission concluded that the regulations would impose no additional economic burdens and would therefore be reasonable.
XI. Classifications and Standards - Special Cases 1. Page 1, Segment 1(a) and 1(b), Upper Arkansas River (proposed as page 1, segment 1) This segment has been re-segmented based on water quality data and other information submitted by Trout Unlimited and Amax, Inc., indicating that water quality and habitat characteristics are different in each of these sub-segments and that there is some variability in the aquatic life present. Also, water supply and agriculture classifications have been dropped on segment 1(a).
2. Page 1, Segments 2(a), 2(b) and 2(c) (proposed as page 1, segment 2) This reach of the Arkansas River has been re-segmented into three sub-segments based upon the request of Trout Unlimited and the evidence supporting such a change. The primary basis for this resegmentation is the severe water quality differences in the three segments due to the impacts of the Leadville Drain and California Gulch, in the upper reaches as well as the diluting effects of Lake Fork on the Arkansas River in segment 2c. However all three segments have been classified Aquatic Life Class 1, since they are water quality limited rather than habitat limited. Standards have been calculated for each segment based upon the existing quality in each segment.
Conflicting evidence was offered on the issue of future improvement of water quality in these segments, from both economic and technology standpoints. Although improvement may result if the quality of water from California Gulch improves, the prospects are too speculative, and it is impossible to predict the degree of improvement that might result. Therefore no “Goals” have been established for these segments.
3. Page 1, Segment 3 (proposed as page 1, segment 3)
4. Page 2, Segment 4 (proposed as page 1, segment 4)
5. Page 2, Segment 6 (proposed as page 1 segment 6)
6. Page 2, Segment 8(a) and 8(b) (Proposed as page 2, segment 8) Testimony indicating considerable water quality degradation immediately below ASARCO's water supply intake necessitated the resegmentation of Iowa Gulch. For Segment 8(b) it is currently unknown as to what levels of cyanide can be achieved by the application of treatment generally recognized as best available technology economically achievable (BATEA), In view of this, a free cyanide standard was not established for this segment. The Commission finds it would be an unreasonable economic burden to ASARCO to meet a cyanide standard in this segment. The Division felt that due to the time required for passage of cyanide through beaver ponds and other features of the segment the cyanide would dissipate to a level where aquatic life would not be disturbed on the lower segment. The testimony provided three basic reasons for the Commission's decision. They are: The economic burden of additional treatment; the requirement that ASARCO meet Best Practical Technology (BPT) or Best Available Technology (BAT) or Best Engineering Judgment (BEJ) regardless of the Commission's actions at this time; and that the dissipation effect would protect the downstream uses.
7. Page 3, Segment 9 (proposed as page 2 segment 9)
8. Page 3, Segment 11 (proposed as page 2 segment 11)
9. Page 4, Segment 16(a), 16(b), and 16(c) (proposed as page 3, segment 16) Special studies conducted in January and August, 1980 by the WQCD showed diverse populations of aquatic macroinvertebrates at all sampling stations located on Middle Tallahassee and Tallahassee Creek. Several types of aquatic insects inhabiting the stream are typically found in cold streams with moderate to fast current.
10. Page 4, Segment 17(a), 17(b) Page 5 Segment 17(c) (proposed as Page 3, segment 17) Segment 17 has been resegmented to take account of natural impediments to the attainment of the Aquatic Life Class 1 classification in segment 17(b). However, segments 17(a) and 17(c) presently supports a wide variety of sensitive species. Water supply was not assigned as a classification for segment 17(b) due to the use not being in place and because of exceedance of the table value for sulfate. There is no anticipated impact on Cottonwood Creek from the proposed Hansen Project.
11. Page 5, Segment 18(a) and 18(b) (proposed as page 3 segment 18) Resegmentation is based on a difference in alkalinity in the two segments.
12. Page 5, Segment 21 (proposed as page 4 segment 18)
13. Page 6, Segment 23 (proposed as page 4, segment 23) An ammonia footnote was agreed to for this segment to eliminate an immediate need for ammonia removal. If needed, it would cost the City of Victor $19.50 per tap. It was argued in testimony that the proposed water supply classification be dropped. However, since ambient quality of the water supports a water supply classification even though the segment's intermittent flow may make it an unreliable water supply, the classification is appropriate.
14. Page 7, Segment 3 . (proposed as page 6, segment 3) Although there is evidence that this segment is a transitional temperature zone, generally, the water temperature is appropriate to support the warm water classification. Both cold and warm water species are present. A warm water classification was adopted to protect downstream quality as the segment flows to warmer water. Evidence of channelization of the streambed and the results of fish surveys indicate that a warm water aquatic life classification is appropriate. A goal for cold water has been rejected because of the predominance of warm water species and due to a lack of evidence that the existence of cold water in this segment is predictable. The Commission also finds that the .06 unionized ammonia standard will not be harmful to the aquatic life in this segment should this level be reached because of the small numbers of cold water species in this segment.
15. Page 8, Segment 8 (proposed as page 7, segment 8)
16. Page 10, Segments 22 and 23 (proposed as page 9, segments 22 and 23) A High Quality Class 2 designation for segments 22 and 23 was based upon testimony that the segments contained the habitat for the two known remaining populations of greenback cutthroat trout which is a federally listed endangered species. Trout Unlimited requested classifications as High Quality Class 1 due to the federal status and the definition for High Quality 1 in the “Basic Standards.” However the High Quality Class 2 was adopted to be consistent with Commission actions in other basins.
17. Page 11, Segment 2 (proposed as page 10, segment 2) The Commission determined that it would not be appropriate to assign an aquatic life classification on this segment. The record indicates that the stream is largely barren of aquatic life except for some migration of the Arkansas Darter from selected tributaries. Because of the widespread social and economic impact which would result from the aquatic life classification and because this stretch of water shows past human induced conditions which appear uncorrectable in a 20 year time period, the aquatic life classification has been eliminated. This segment was classified as a water supply because it is hydraulically connected to the Widefield aquifer, a major source of domestic water for several communities. The metals standards represent table numbers for a domestic water supply use.
17. Page 11, Segment 3(a) and 3(b) . (proposed as page 10 segment 3) Segment 3 has been resegmented into 2 sub segments in order to recognize the presence of the Arkansas Darter in 3 tributaries to Fountain Creek as specified in segment 3(b). The standards adopted for segment 3(b) are intended to protect the Arkansas Darter.
18. Page 13, Segment 1 (proposed as page 12, segment 1) The Commission adopted the aquatic life class 2 warm water classification because aquatic life are present in this segment despite some degraded conditions. Also, the evidence indicates perennial flows in this stream segment.
19. Page 13, Segments 5(a) and 5(b); Page 14, Segments 6(a) and 6(b) (proposed as page 12, segments 5 and 6)
20. Page 14, Segment 8(a) and 8(b) (proposed as page 13 and segment 8) This segment was proposed as a high quality class 2 stream because it provides habitat for a threatened species i.e., the Colorado Cutthroat Trout. However, because this segment is located entirely within the boundaries of private property the Commission assigned specific use classifications, including cold water aquatic life class 1. The standards applicable to protect the aquatic life class 1 classification or sufficient to protect the Cutthroat Trout in this segment and no degradation of water quality for aquatic life habitat will result from the assignment of this classification.
1. INTRODUCTION The Water Quality Control Commission is charged with the responsibility to conserve, protect, and improve the quality of state waters pursuant to C.R.S. 1973, 25-8-101 et seq. The Commission is further empowered and directed to classify waters of the State and to promulgate water quality standards for any measurable characteristic of the water in order to protect both the uses in place and those that can be reasonably expected in the future. (25-8-203 and 25-8-204) The above-titled document assigns use classifications and standards for the state waters in the listed areas in accordance with the “basic regulations” adopted May 22, 1979. The measurable fiscal impacts which may be caused by these regulations are as follows; - Cost of construction due to requirements for increased levels of treatment by municipal waste treatment facilities;
- Cost of Operation and Maintenance associated with increased levels of treatment required of industrial and commercial dischargers;
- Cost of instream monitoring and laboratory analysis for new parameters added by the standards.
Dischargers will not be required by the adoption of these regulations to do stream monitoring. The state, federal and local agencies now doing instream monitoring will have some increased cost; however, any additional frequency should be done to improve state surveillance and would be needed regardless of standard changes.
The stream classifications and standards adopted by the Commission will protect the water uses primarily through control of point source pollution. Nonpoint source pollution will be controlled primarily through management practices which are in existence or which will be implemented in the future. Future management practices need careful consideration and may be the result of 208 area-wide wastewater management plans developed by regional planning agencies and being updated annually. These plans involve local governments with general assistance from state government. Some of the possible nonpoint source pollution may be controlled through “Control Regulations” yet to be promulgated by the Commission. These types of controls could involve runoff from construction, mining activities, and urban areas. It is not certain what controls are needed at this time and there is no way that possible costs can be identified at this time. Persons who benefit from standards which will protect existing and future anticipated uses can be identified as all persons benefiting from recreation, municipal water supply, and agriculture. These benefits are directly economic for agriculture, industry, and municipalities whose health benefit costs are reduced by having clean water, and are both economic and nonquantifiable for some uses such as fishing, recreation, and the aesthetic value of clean waters. Furthermore, benefits will result from human health protection and lack of debilitating disease. Figures have been developed for a recreation/fishing day which can be applied to that aspect of a water use; however, figures which have been developed for total recreation/fishing day uses have been developed statewide and could not be applied region-by-region or stream-by-stream. The uses of water in this region are adequately protected by these standards. Most municipal treatment facilities and industrial facilities are currently adequate, or are already being upgraded, in order to meet previous requirements. Any additional facilities or expansions in this region will generally be caused by increased capacity required because of population growths or industrial enlargement. Industries are required by federal statute to meet effluent limitations described as “Best Available Technology Economically Achievable” (BAT) by 1983 or 1984. For most major industries in this region, the water quality standards should not require treatment beyond these limitations.
The fiscal impact of any regulatory decision must take into account only the incremental costs explicitly associated with the regulations as finally promulgated. Costs and expenditures associated with the status quo, regulations of other regulatory agencies, or regulations already in effect should not be included in an assessment of the fiscal impact of the Arkansas Basin classifications.
In addition, a distinction must be made between actual expenditures or dislocations that will be immediately or unavoidably necessary upon promulgation of these classifications and standards, and those costs which are speculative in nature. In keeping with concepts of “ExpectedValue” , it is proper for the Commission to place more emphasis on definite impacts. With the passage in 1981 of Senate Bill 10, amending the Colorado Water Quality Control Act, it became incumbent upon the Water Quality Control Commission to consider the economic impact of their decisions with more emphasis placed upon the concept of the “Economic Reasonableness” . Supplementary hearings were held by the Commission on the Arkansas Basin to consider the new provisions of the Act. Charged with such a mandate, the Commission was quite sensitive to the objective of minimizing the socio-economic “price” of clean water while adhering to the antidegradation policy that water quality be preserved and protected in all cases, and improved wherever feasible.
The analysis and data which follows is derived primarily from testimony and exhibits offered by interested parties during the course of the rulemaking hearings. This was supplemented by staff estimates of potential impacts upon other major entities who were not formally represented. The impacts are separately presented for the public and private sections. Except for instances where explicit testimony was given by interested parties at the rulemaking hearing, no attempt has been made to identify future development costs as this type of data is not readily available and estimation techniques are dependent upon many highly subjective assumptions. Finally, to fully illustrate the degree to which costs were minimized where possible, two tables for each sector are presented.
The first table itemizes the impacts of the classifications as proposed while the second table depicts the impacts of the classifications as finalized.
II. FISCAL IMPACT: PUBLIC SECTOR The primary fiscal impact to the public sector in this basin involves the domestic wastewater treatment costs associated with the stream classifications and water quality standards. Other costs, such as tax and employment base impacts due to foregone industrial development opportunities or mitigated growth potentials, can be theoretically postulated but are difficult to quantify. Generally it is recognized that higher tap fees, service charges or property taxes associated with increased treatment costs can potentially affect industrial siting decisions. However, this is not as significant as increased levels of treatment that may be required of industries if they are dischargers. While the Commission acknowledges the existence of such potentials, the lack of firm evidence and actual tax base impact estimates make deliberative assessment impractical.
Security Ammonia Conv. $ 1.53 Million (1980)
Monument Ammonia Conv. $ 465,000 (1980)
Pueblo Ammonia Conv. $ 14.1 Million Total .
Victor Ammonia Conv. $164,000 (1980)
La Junta Ammonia Conv $ 2.3 M (Bio-Plant) (1980)
. . $ 700 K (B-P Chlor) (1980)
Trinidad* Ammonia Conv. $ 1.0 Million (1980)
Palmer Lake* Ammonia Conv. $ 250,000 – $500,000 (1980)
Woodmore* Ammonia Conv. $ 750,000 (1980)
Colo. City* Ammonia Conv. $ 0–500,000 (1980)
Woodland Park* Ammonia Conv. $ 750K–1M (1980)
Salida Ammonia Conv. $ 1 Million (1980)
Rye Slight operational . .
Canon City Incremental costs can be . .
Florence Participation in Fremont . .
* Estimated potential expenditure - actual requirements and fiscal impact is undermined. ** In addition to this Colorado Springs estimate of expenditures, representatives of the Pikes Peak Area Council of Governments estimated that the counties of Teller and El Paso will have to expend approximately $29 million dollars to meet the standards of inorganic waste.
Table Two FISCAL IMPACT ON MUNICIPALITIES OF FINAL CLASSIFICATIONS MUNICIPALITIES NEEDED FACILITY ESTIMATED YEAR OF ESTIMATE CAPITAL EXPENDITURE Monument Ammonia Conv. $ 465,000 (1980)
Woodland Park* Ammonia Conv. $ 750K–1M (1980)
Rye Slight operational . .
Canon City Incremental costs can be . .
Florence Participation in Fremont . .
* Estimated potential expenditure - actual requirements and fiscal impact is undetermined.
III. FISCAL IMPACT: PRIVATE SECTOR It can be assumed that nearly every commercial entity with the Arkansas Basin would or could be affected in some way by the classifications regardless of whether they are dischargers or simply customers of water suppliers. Many firms apparently regarded utility increases as an additional cost of doing business in this locale and chose not to present evidence at the rulemaking hearings for this basin. It might be concluded that some felt there would be no impact or that it was unidentifiable at this time. However, some of the larger private interests that have discharge permits or would be seeking them in the future presented testimony indicating costs associated with metals removal and other treatment costs. Table Three summarizes the impact of the proposed classifications as testified to by interested parties. Not all of the costs presented in Table Three are additional increments due to the proposed classifications and standards. Some reflect baseline treatment already required by permit, treatment capability already in place, costs incurred by other regulations, or potential costs for operations not currently active. A comparison between the two tables reveals a striking difference between “what could be” and “what will most likely be” . The proposed classifications and standards had a potential impact of nearly 35 million dollars in capital expenditures and over one million dollars in annual expenses. The fiscal impacts of the classifications as finalized dramatically demonstrate the degree to which proper analysis and consideration of economic issues were taken into account in the deliberative process. In the case of Public Service Company, the proposed aluminum and copper standards to protect aquatic life were stringent enough that they would have forced PSC into a zero discharge at a cost of over 20 million dollars. As the flow of the affected segment is largely PSC effluent, the very effort to protect aquatic life would do it great harm as the stream could be dry much of the time. Since this was a proposed upgrading, the final classifications and relaxed standards are consistent with the anti-degradation policy while eliminating a substantial cost. The cost figures for ASARCO fall out because they reflect baseline treatment already required by permit and are thus not attributable to the finalized regulations. Cyprus Mines, the only potential uranium discharger in the basin, is not currently in operation so these costs become additional costs of doing business rather than actually realized burdens. It was not established whether or not Cyprus Mines would have to go beyond chemical treatment so the other costs for more exotic processes drop out. In addition, the phase of operation requiring water treatment would last only three years, so the annual operation and maintenance costs will not be incurred throughout the life of the project. Finally, changes in segment 16B may decrease costs associated with uranium and sulfide removal.
TABLE THREE FISCAL IMPACT ON PRIVATE SECTOR OF PROPOSED CLASSIFICATIONS COMPANY NAME PARAMETER ESTIMATED YEAR OF ESTIMATE CAPITAL EXPENDITURE 1 Heavy Metals Uranium $ 1.9 Million (chemical (1980)
Project)
. . . .
. . $2.2 Million (Reverse (1980)
. . $ 435,0001 (Ion (1980)
ASARCO Heavy Metals $ 2.25 Million (1980)
CF&I Steel Heavy Metals Cyanide $ 1.38 Million (1980)
2 Metals, Chem. $ 250K–$2 Million (1980)
Public Service Metals $ 23 Million Net Present .
2 Hewlett-Packard is referring to a future plant expansion in the Colorado Springs area and these are the estimates of the costs that would be incurred to meet heavy metals standards due to the manufacturing nature of the new plant. TABLE FOUR FISCAL IMPACT ON PRIVATE SECTOR OF FINALIZED CLASSIFICATIONS COMPANY NAME PARAMETER ESTIMATED YEAR OF ESTIMATE CAPITAL EXPENDITURE 1 Heavy Metals Uranium $ 1.9 Million (chemical (1980)
Project)
. . . .
CF&I Steel Heavy Metals Cyanide $ 1.38 Million (1980)
Cripple Creek and Victor Metals Some treatment costs can . Gold Mine be assumed for mine drainage. Not currently in operation-still under study.
1 It is not determined if Cyprus Mines will be required to go beyond chemical treatment to comply with the standards and whatever permit may be written controlling their discharge. Nor currently in Operation. The only potential uranium discharger in the Arkansas Basin.
The Commission at a public rulemaking hearing November 8, 1982, adopted clerical and editorial corrections to the Commission's current regulations numbered respectively 3.2.0, 3.4.0, 3.6.0 and 3.8.0. These regulations are contained in Article 3, Water Quality Standards, of the Policies, Regulations, and Guidelines of the Water Quality Control Commission . (5CCR 1002-8) In adopting these corrections the Commission considered the economic reasonableness of its action, except as specified the corrections in no way change the classifications and numeric standards originally adopted by the Commission. Other than written comment from the City of Westminster no testimony was offered at the public hearing.
The consolidated changes adopted by the Commission are included in this Basis and Purpose for information. The Secretary of State was provided corrected pages for each of the regulations as replacements for the regulations previously published.
Dated this 8th day of November, 1982 at Denver, Colorado.
32.11 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE - SEGMENT
Physical conditions in various portions of Segment 8a such as substrate, low flow, depth, lack of pools, freeze-out, and physical barriers preclude a viable fish population, and more stringent water quality standards than adopted cannot be justified for the protection of macroinvertebrate only, based on the aquatic life classification. The macroinvertebrate population which does exist in the segment does not appear stressed at ambient levels of pollutant concentration. Ambient levels of pollutant concentration do not now jeopardize downstream aquatic life. Testimony does not support the conclusion that the imposition of more stringent metals limits would lead to an improved aquatic habitat. At such time as water quality improvements downstream in Segments 8b or 9 indicate either a potential for a viable fish community in Segment 8a or an approved fishery in Segment 8b or 9 and where the macroinvertebrate population in the upper segment is necessary for that fish community's survival, or during the triennial review of the basin, the standards for this segment may need to be reexamined to assure that downstream uses continue to be protected.
From evidence received at the public hearing, it appeared that the existing stream standards for copper and lead were periodically exceeded in several reaches of the segment. However, there was considerable disagreement among the parties and staff over the appropriateness and accuracy of the data presented at the hearing. Differences in analytical techniques resulted in non-comparable data, making the calculation of ambient quality, based on a determination of the mean value, difficult. The temporary modifications adopted for copper and lead reflect a continuation of ambient quality, which protect designated uses and recognize the need to protect the drinking water supply diversion at the lower end of the segment.
The agriculture use classification is retained because there is conflicting evidence regarding the existence and extent of the use necessitating further study. The standards in effect to protect this use do not impact the Sherman Tunnel discharge.
No change was made to the other pollutants for which change had originally been proposed because the data available did not conclusively support a change, and because the current stream standards adequately protect the classified uses. Evidence presented at the hearing indicated that the original classified uses remained appropriate.
BAT limits are being met by the sole discharger to the segment, the Hecla Mining Company. There has been no demonstration that more stringent water quality standards will provide any benefits to the aquatic life in the stream. The adopted temporary modifications will not require the discharger to provide additional treatment where there is in the record insufficient information to justify the adoption of standards that could result in additional treatment requirements. The adopted temporary modifications are thus determined to be economically reasonable.
It is further declared to be the Commission's intention that the temporary modifications are being established at this time to allow all interested persons to collect additional data to be analyzed in a uniform fashion and in conformance with existing Commission policies as well as upcoming modifications thereto, so that at such time as the temporary modifications expire or at any other appropriate time, the Commission will be able to determine appropriate final standards for all parameters on this segment. FISCAL IMPACT STATEMENT - SEGMENT 8a, IOWA GULCH, UPPER ARKANSAS RIVER, ARKANSAS RIVER BASIN The establishment of temporary modifications to the water quality numeric standards for lead and copper dramatically reduce the probability of further treatment requirements for mined located in this segment. Estimates indicate a potential savings of up to $300,000 capital costs and $16,000 operations and maintenance to accrue to the owner of the Sherman Mine. The Commission finds that these cost savings will not be had at the expense of current beneficial use degradation, based upon the evidence available.
There will be no fiscal impact on any other government or private entities.
32.12 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE:
The provisions of 25-8-202(1)(a)(b) and (2); and 25-8-204 C.R.S. provide the specific statutory authority for adding the numeric standards that were proposed.
The Commission also adopted in compliance with 24-4-103(4) C.R.S. the following statements of basis and purpose and fiscal impact.
BASIS AND PURPOSE - ARKANSAS:
The basis and purpose for the changes by segment is given below: Segment 1, Upper Arkansas River - Two wilderness areas, Mt. Massive and Collegiate Peaks, were designated after the 1980 hearings. Creation of a new segment with High Quality - Class 2 designation will protect these areas and is consistent with Commission actions in other basins. Segment 2b, Upper Arkansas River - Present description does not define the segment because of a typographical error. New description will define the segment. Segment 3, Upper Arkansas River - Typographical error in cadmium standard. Change to 0.001 mg/l reflects the adopted standard.
Segment 25, Upper Arkansas River - Cottonwood Creek has been identified by the Colorado Division of Wildlife as habitat of the greenback cutthroat trout which is a State threatened and Federally endangered species. Creation of a new segment with High Quality - Class 2 designation will provide protection to the creek and is consistent with Commission actions in other basins. Segment 4, Middle Arkansas River - Present description does not except Segment 24, should the Commission decide to create a new Segment 24. The change will be needed if Segment 24 is adopted.
Segment 15, Middle Arkansas River - Typographical error for zinc standard. Original testimony showed the ambient level of zinc to be 0.2 mg/l in this segment. Change will reflect the standard as adopted by the Commission in 1981.
Segment 24, Middle Arkansas River - The waters are the only known habitat in Colorado for the Southern Red Belly Dace, according to the Colorado Division of Wildlife. Creation of this new segment with a High Quality - Class 2 designation should protect this species. Segment 2, Fountain Creek - Drinking water standard is for total cyanide. The change in cyanide description from free to total will reflect what is required to protect the domestic water supply use. Segment 9, Lower Arkansas River - The standards reflect a classification of Cold Water Aquatic Life - Class 1 for waters that are Warm water Aquatic Life - Class 1 habitat. The change will reflect the Commission's intent in adopting the classifications and standards for this segment. Segment 10, Lower Arkansas River - The standard for dissolved oxygen (D.O.), unionized ammonia (NH ) and nitrite (NO ) are table numbers for a Cold Water Aquatic Life - Class 1 designation. 3 2 The change in the standards will reflect the Commission's intent in adapting the standards in 1981 and will provide protection to the Warm Water Aquatic Life residents to the waters. FISCAL IMPACT STATEMENT - ARKANSAS RIVER BASIN These regulations more accurately reflect the protections necessary for wilderness areas and rare and endangered species. In some cases, the only known habitat for certain species is identified. It is not anticipated that these changes will impact dischargers, except as a future development potential, yet will afford the benefit of protection of beneficial uses. In view of these facts, the Commission expects these regulations to be economically reasonable.
ADOPTED: December 6, 1985
32.13 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE SEGMENT
BASIS AND PURPOSE:
Leadville Corporation owns and operates the Sherman Mine at the upper end of Iowa Gulch on the side of Mount Sherman, a 14,000 foot peak. Under the provisions of C.R.S. 25-8-207, Leadville Corporation petitioned for a rulemaking hearing regarding Segment 8a, Iowa Gulch, to review whether new material facts demonstrate that the aquatic life classification is in error for Segment 8a, due to severe physical, natural, climatic, and structural constraints existing in Segment 8a which preclude a viable habitat for fish or shellfish life. Leadville Corporation also sought review of the agriculture classification for Segment 8a, stating that Segment 8a has no existing use or reasonably anticipated future use for agricultural purposes.
Leadville Corporation also sought a change in the applicable water quality standards for Segment 8a to reflect protection only of the domestic drinking water supply and recreation class 2 classifications of Segment 8a. The water quality standards for protection of the two uses proposed to be retained were proposed to be the table values from the Commission's Basic Standards and Methodologies Regulation. In 1985, a hearing was held in which similar requests were made to delete classifications and modify water quality standards. Those 1985 requests were denied, but the Commission granted a temporary modification to the water quality standards for lead and copper in Segment 8a, Iowa Gulch. This temporary modification altered the standard for copper from 0.007 mg/l to 0.05 mg/l and the standard for lead from 0.022 mg/l to 0.05 mg/l. The temporary modification expires March 5, 1987. In connection with granting the temporary modification the Commission directed Hecla Mining Co., the predecessor of Leadville Corporation, to conduct a water quality sampling program on Iowa Gulch, Segment 8a, and to analyze the results according to a laboratory method recommended by the Water Quality Control Division. The purpose of the sampling and analysis program, in part, was to ascertain whether the ambient water quality of Segment 8a, Iowa Gulch, justifies the standards which had been previously set by the Commission for this Segment.
Leadville Corporation asserted that the sampling and analysis program showed that the ambient water quality of Iowa Gulch, Segment 8a, exceeds the values the Commission set for at least three metals: copper, lead and cadmium, and that the existing and reasonably anticipated water uses in Segment 8a would not be adversely affected by a change in water quality standards to the table values, and, further, that the existing uses of Segment 8a would be protected if the requested rulemaking proposal were adopted by the Commission. Prior to the hearing, Leadville Corporation and Parkville Water District requested resegmentation of Segment 8a into two separate stream segments. Summary of Action:
Segment 8a of Iowa Gulch is resegmented into Segments 8a1 and 8a2, with the division between the new segments being at a point immediately below the confluence of the Hilltop Saddle drainage with Iowa Gulch. The existing classifications for Segment 8a are retained for new Segments 8a1 and 8a2. The existing numerical standards for Segment 8a are retained for new Segments 8a1 and 8a2, except for the following revisions:
The Commission finds that resegmentation of Segment 8a of Iowa Gulch into Segments 8a1 and 8a2 is appropriate. The evidence presented demonstrates that the stream has different physical characteristic above and below the Hilltop Saddle drainage confluence. For example, there is increased stream flow below this confluence. In addition, ambient water quality differs significantly above and below this point. Finally, this resegmentation will allow the adoption of more stringent water quality standards for Segment 8a2 to fully protect the domestic water supply and other uses of that segment, while avoiding more stringent standards for the upstream Segment 8a1. This results from handling the water quality data for these two segments separately, rather than averaging all Segment 8a data. Leadville Corporation, Parkville Water District, and the Water Quality Control Division agreed that this resegmentation is appropriate.
Classifications:
The Commission finds that there has been no demonstration that the existing aquatic life and agriculture use classifications for Segment 8a were based upon material assumptions that were in error or no longer apply, and accordingly the Commission reconfirms the decision made in 1985 to retain the existing classifications. Moreover, the Commission finds that there has been no demonstration that the aquatic life classification for Segment 8a is more stringent than is necessary to protect fish life, shellfish life, and wildlife in a water body segment which is reasonably capable of sustaining such fish life, shellfish life, and wildlife from the standpoint of physical, streambed, flow, habitat, climatic, and other pertinent characteristics.
Notwithstanding the presence of certain physical barriers to fish in the new Segments 8a1 and 8a2, both are typical high mountain streams. For example, the macroinvertibrate populations are representative of typical streams of this type. No substantial evidence was presented to demonstrate that the previously established agriculture classification is erroneous. There was evidence presented of possible agricultural use of Segments 8a1 and 8a2. Therefore, the Commission has decided to retain the existing use classifications for both Segment 8a1 and 8a2. Leadville Corporation, Parkville Water District and the Water Quality Control Division stipulated to the retention of all existing classifications for Segment 8a2. Standards:
Based upon the new ambient water quality data submitted at the hearing, the Commission has revised the water quality standards for Segment 8a of Iowa Gulch for four parameters: copper, lead, cadmium, and zinc. Separate standards have been established for new Segments 8a1 and 8a2. For Segment 8a2, Leadville Corporation and Parkville Water District stipulated their agreement with the standards recommended by the Division. At the hearing, Leadville corporation objected only to the Division's proposed lead standard for Segment 8a1.
In establishing revised standards for Segment 8a1, the Commission rejected as a matter of policy the position of Leadville Corporation that ambient water quality data from samples taken at the Sherman Mine Portal should be included in the calculation of standards. The Sherman Mine Portal drainage is a permitted point source discharge. Even if the source of this discharge is essentially ground water, this discharge to the stream would not exist except for the presence of mining operations. The final revised standards take into account additional data submitted by Leadville Corporation and admitted into the record by the Commission on February 3, 1987. The revised standards are merely a recalculation of ambient quality for the relevant segments based on new data. Recalculation of ambient water quality for Segments 8a1 and 8a2 was done consistently with the policy of excluding certain “outliers” based on the screening process known as Chauvenet's criteria and two “outliers” for lead were excluded from the Division's data base as a result. The revisions do not constitute a downgrading of classified uses for these segments and do not authorize any change in the existing water quality of these segments. For lead and zinc in both segments, and for cadmium in Segment 8a2, the revised standards are in fact more stringent than existing standards.
FISCAL IMPACT STATEMENT:
The retention of the existing classifications for the resegmented Segments 8a1 and 8a2 of Iowa Gulch creates no new fiscal costs of benefits. The revised numerical standards for these segments may have fiscal impacts. The establishment of more stringent numerical standards for Segment 8a2 will provide better protection for the uses in that segment, including the domestic water supply diversion by the Parkville Water District. The water users and ratepayers of the Parkville Water District may benefit economically in terms of water treatment costs and reduced health impacts. Leadville Corporation submitted evidence that adoption of the revised numerical standards for Segment 8a1 will require an expenditure of $400,000 for treatment of the Sherman Mine Portal discharge. Currently, this is the only permitted mine water discharge in the State that is not treated. Although a determination whether such treatment will be required was not a subject of this hearing, the Commission finds that even if such costs are incurred, this economic impact is justified since the standards established are reasonably necessary to protect the uses of this segment of Iowa Gulch. The actions taken are not expected to have a significant fiscal impact on the State's administration of water quality control programs.
Dated this 2nd day of March, 1987, at Denver, Colorado. FINDINGS REGARDING BASIS FOR EMERGENCY RULE SEPTEMBER 11, 1990: The Commission finds that the immediate adoption of this regulation is imperatively necessary for the preservation of public health, safety, or welfare and that compliance with normal notice requirements would be contrary to the public interest. The reasons for this finding are that action needs to be taken during this winter season to minimize the risk of uncontrolled releases of highly saline water from Cheraw Lake. Specifically, there is a possibility of significant damage to agricultural and domestic water supply uses downstream of Cheraw Lake if undiluted releases occur. There was evidence that the water level in Cheraw Lake currently is near the top of the outlet structure and that therefore releases could occur in the near future, depending on precipitation and return flows into the Lake. The two release prohibitions which are scheduled to go into effect in 1990 would, of course, not become effective during the life of this emergency rule. However, the Commission finds that the two-year period established in the regulation is necessary for affected entities to take the actions necessary to come into compliance by that time. Necessary actions would include assessment of the problem, analysis of the feasibility of compliance options, arrangements for financing, and completion of design and implementation of any structures or facilities to achieve compliance. Therefore, the Commission finds there is an emergency basis for adopting these provisions, in order to provide adequate notice to affected entities, should these or similar provisions be adopted as permanent regulations. At the same time, the Commission intends to consider at the permanent adoption hearing any other options that may be developed by the Division or outside parties prior to that time. Paragraph 4.4.2(3) prohibits any release of water from water collection systems into Cheraw Lake after March 15, 1990, irrespective of the quality of such releases. From the evidence provided, it appears that even if distilled water were released into Cheraw Lake, after mixing there is a substantial risk that the water released from Cheraw Lake would be of an unacceptable quality. Moreover, long-term downstream protection can not be accomplished solely by regulating controlled releases, since uncontrolled releases are likely to occur, depending on precipitation and return flows. Therefore water releases into Cheraw must be controlled in order to control outflows. From the information currently available to the Commission, the limitation on releases into Cheraw Lake should have no adverse impact on water rights. The testimony indicated that there are no current water rights to the water in Cheraw Lake, and did not indicate that any water users upgradient of the Lake currently use the return flows that run into the Lake. In fact, diverting water around Cheraw Lake to comply with section 4.4.2(3) may have a beneficial impact on water rights by increasing the water supply downstream. Of course, should different information regarding a potential impact on water rights become available prior to the permanent adoption hearing, that may affect any action that the Commission would take as a result of that hearing.
Because of the Commission's extremely full agenda and the time necessary to develop a proposed regulation on this complex issue, the Commission finds that it may be necessary for the emergency regulation to be in effect for up to one year. Therefore, the regulation is to be effective immediately and continue in effect until the effective date of permanent regulations or for one year, whichever comes first. The Commission has agreed to schedule a permanent adoption hearing for November 7, 1988, which is the earliest available time on the Commission's agenda. The purpose of this regulation is to protect the agricultural uses of water in Horse Creek (Otero and Bent counties) from the highly saline discharges from tributary Cheraw Lake, while also avoiding an unacceptable adverse impact on other downstream water uses, particularly domestic water supplies. The saline condition of water in Cheraw Lake appears to be caused by highly alkaline native soils in the area together with routing of irrigation return flows to the lake. Traditionally, the shortage of water in the Arkansas River Basin has prevented the lake from overflowing into Horse Creek. Evaporation losses then contributed to the increase in salinity which has exceeded 17000 mg/l (TDS) in the upper layer and 60,000 mg/l at the bottom of the lake based on samples collected by the Division and the USGS. The excess of water caused by the past “wet” years has caused levels in the lake to rise significantly which, in turn, threatened to cause property damage to State Highway 109 and the Town of Cheraw. This led several parties to effect releases from the lake which have damaged and endangered the agricultural use downstream on Horse Creek. This statement is supported by the EPA “Red Book: criteria for irrigation water and Division water quality investigations of the Lake and Horse Creek. The ambient quality of Horse Creek has exceeded 5000 ppm TDS without influence from Cheraw Lake based on the existing water quality database. Since the agricultural use of the Horse Creek water under those conditions did not appear to be impaired, the salinity levels of Horse Creek will be controlled based on the mean plus one standard deviation of the measured TDS levels in Horse Creek, which is 5270 mg/l. The TDS standard adopted for Horse Creek should help assure that this level is met in the future. FISCAL IMPACT STATEMENT REGARDING CHERAW LAKE EMERGENCY CONTROL REGULATION AND HORSE CREEK SALINITY STANDARD; AS ADOPTED JANUARY 22, 1988 One group of persons who may incur additional costs as a result of these emergency regulations is anyone who may effect a controlled release of water from Cheraw Lake. Costs, which have not been quantified, would be incurred principally by acquiring a source of dilution water so that releases comply with the salinity limitation. In addition, if the provisions of the emergency regulations are permanently adopted, the prohibition of the release of water from water collection systems into Cheraw Lake after March 15, 1990 may impose substantial costs on the owners of water collection systems who would have to reroute such water away from Cheraw Lake.
The primary persons potentially benefiting from the regulations are agricultural and domestic water users downstream. These persons may benefit by the requirement for water released from Cheraw Lake to be diluted, and from the prohibition of releases of water into Cheraw Lake if that becomes permanent (since that prohibition would minimize the likelihood of further releases from Cheraw Lake). There was evidence submitted that even diluted water released from Cheraw Lake adversely impact downstream users. However, whether any such impacts would be greater or less than would occur without the emergency regulations depends on speculation regarding future precipitation and resulting water use patterns.
The emergency regulations should not have a significant fiscal impact on the State's administration of the water quality control program.
32.14 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE (NOVEMBER,
The provisions of 25-8-202(1)(b) and (2); and 25-8-204; C.R.S. provide the specific statutory authority for adoption of the attached regulatory amendments. The Commission also adopted in compliance with 24- 4-103(4), C.R.S., the following Statement of Basis and Purpose. BASIS AND PURPOSE:
The purpose of the water quality standard for TDS adopted for Horse Creek is to help protect downstream agricultural and domestic water supply uses, to the degree feasible, taking ambient water quality conditions into account. This standard is intended to operate in conjunction with the Cheraw Lake control regulation, which is being adopted concurrently. The purpose of the control regulation is to protect the agricultural uses of water in Horse Creek (Otero and Bent Counties) from the highly saline discharges from tributary Cheraw Lake, while also avoiding an unacceptable adverse impact on other downstream water uses, particularly domestic water supplies.
The regulation takes into account the intermittent nature of any discharges from Cheraw Lake, and the possibility that any discharge could be diluted before the water reaches Horse Creek. The regulation does not impose any specific treatment or best management practice requirements. Rather, it provides flexibility regarding the means of compliance, so long as the specific level of salinity can be achieved in Horse Creek.
The saline condition of water in Cheraw Lake appears to be caused by highly alkaline native soils in the area together with routing of irrigation return flows to the lake. Traditionally, topography and the shortage of water in the Arkansas River Basin has prevented the lake from overflowing into Horse Creek. Evaporation losses then contributed to the increase in salinity which has exceeded 17000 mg/l (TDS) in the upper layer and 60000 mg/l at the bottom of the lake based on samples collected by the Division and the USGS. The excess of water caused by the past “wet” years has caused levels in the lake to rise significantly which, in turn, threatened to cause property damage to State Highway 109 and the Town of Cheraw. This led several parties to effect releases from the lake which have damaged and endangered the agricultural use downstream on Horse Creek. This statement is supported by the EPA “Red Book” criteria for irrigation water and Division and USGS water quality investigations of the Lake and Horse Creek.
The ambient quality of Horse Creek has exceeded 5000 ppm TDS without influence from Cheraw Lake based on the existing water quality database. Since the agricultural use of Horse Creek water was not impaired under those conditions, salinity levels of Horse Creek will be controlled based on the 85th percentile of 65 USGS measurements of specific conductance prior to the 1985 releases from Cheraw Lake. This value was then converted to TDS using a linear regression developed by USGS and Division staff. The calculated TDS standards is 4300 mg/l.
1. Town of Cheraw 2. Holbrook Drainage District 3. Holbrook Mutual Irrigating Company 4. Arkansas Valley Ditch Association 5. Catlin Canal Company 6. High Line Canal Company 7. Board of County Commissioners, County of Otero 8. David & Dolores Direzza 9. George L. Bender and Sam Turner
32.15 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE;
The provisions of 25-8-202(1)(a), (b) and (2); 25-8-203; 25-8-204; and 25-8-402 C.R.S. provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted, in compliance with 24-4-103(4), C.R.S., the following statement of basis and purpose. Basis and Purpose:
First, the Commission has adopted new introductory language for the tables in section 6. The purpose of this language is to explain the new references to “table value standards” (TVS) that are contained in the Tables. The other changes considered and adopted are addressed below by segment.
A. Aquatic Life Class 1 with Table Values; New High Quality 2 Designations Upper Arkansas segments 12, 13, 15, 16a, 16c, 17a, 17c, 18a, 19, 20, 23, 24 Middle Arkansas segments 5, 6, 9, 10, 11, 14, 16, 19, 20, 21 Fountain Creek segments 4 and 5 Lower Arkansas segments 3, 5b, 6a, 8, 11 Numerical standards for metals for these segments have in most instances previously been based on table values contained in Table III of the Basic Standards and Methodologies for Surface Water. Table III has been substantially revised, effective September 30, 1988. From the information available, it appears that the existing quality of these segments meets or exceeds the quality specified by the revised criteria in Table III, and new acute and chronic table value standards based thereon have therefore been adopted. There are also some of these segments whose previous standards were values based on alkalinity ranges. However, these segments generally have much higher hardness than alkalinity, and the new table values (based on hardness-dependent equations) are now appropriate as standards. Second, in addition to these standards changes, the use classifications have been revised where necessary so that each of these segments has the following classifications: Recreation - Class 1 Cold Water Aquatic Life - Class 1 Water Supply Agriculture These classifications are appropriate because the existing quality is adequate to protect these uses.
B. Existing High Quality 2 Segments; New Classifications and Standards Upper Arkansas segments 1a, 25 Middle Arkansas segments 22, 23, 24 These segments were already described as High Quality Class 2, and available information indicates that the parallel new High Quality 2 designation continues to be appropriate for each. Upper Arkansas segment 1a is within the Collegiate Peaks wilderness area. Upper Arkansas segment 25 and Middle Arkansas segments 22, 23, and 24 contain an endangered species of cutthroat trout. In addition, the following use classifications and associated table value standards were adopted for these segments:
C. New Use-Protected Designations; No Change in Numeric Standards Upper Arkansas segments 8a1, 8a2, 14, 22, 26 Middle Arkansas segments 4, 13, 18 Fountain Creek segments 3a, 8 Lower Arkansas segments 2, 6b, 13 Cimarron River segment 1 These segments all qualify for a use-protected designation based on their present classifications. Lower Arkansas segment 6b and Upper Arkansas segments 8a1, 8a2, and 14 have cold water class 2 classifications. The remaining segments have warm water class 2 classifications. Existing standards are recommended because these segments either have no metal standards or because no dissolved metals data is available for them at this time (Upper Arkansas segments 8a1 and 8a2).
D. New Use-Protected Designations; Revised Numeric Standards Middle Arkansas segments 3, 7, 8, 15, 17 Fountain Creek segments 6 and 7 Lower Arkansas segments 1, 4, 7, 9, 14 Cimarron River segment 2 Middle Arkansas segments 7, 8, 15 and 17; Fountain Creek segments 6, 7; Lower Arkansas segments 1, 4, 7, 9 and 14, and Cimarron River segment 2 are qualified for a use-protected designation because they are classified recreation class 2 and aquatic life warm class 1 or 2. Table value standards are adopted for all constituents, except as noted below. Segment Constituent(s)
E. No Change in Designation; Revised Numeric Standards Upper Arkansas segments 1b, 1c, 2a, 2b, 2c, 3, 4, 5, 6, 10, 16b, 17b, 21, 27 Middle Arkansas segments 1, 2, 12 Fountain Creek segments 3b, 9 Lower Arkansas segments 5a, 10, 10a, 12, 12a The principal issues considered for segment 1b of the Upper Arkansas were the addition of an agriculture classification and the assignment of ambient based standards for zinc, lead, and copper. Consideration of a use-protected designation was also discussed but rejected because the data was in total recoverable form and not dissolved. The Commission declined to adopt the agriculture classification because although the quality of the water would support the use, the water was not currently being used for this purpose and was not likely to be in the future. Table value standards were adopted for zinc, lead and copper with a temporary modification of 250 ug/l for zinc, 12 ug/L for lead and 10 ug/L for copper, each as total recoverable, to expire December 31, 1992. In setting these standards, the Commission rejected deletion of the runoff data and considered adopting seasonal standards. Seasonal standards were not adopted because this would result in spring runoff standards several times higher than the acute criterion. The Commission's action in adopting the temporary modifications and underlying standards for zinc, lead, and copper on segment 1b assumes that dissolved data will be available for the next triennial review (1991), and that revisions to both the temporary modifications and the underlying standards, if appropriate, can be made at that time.
Existing use classifications (Recreation 1, warm water aquatic life 1, water supply, and agriculture) and TVS were adopted for segments 10a and 12a. Segments 10a and 12a were not designated high quality 2.
Consideration of standards for Upper Arkansas segments 2a, 2b and 6 was continued until April, 1990 because of concerns that proposed standards were not protective of aquatic life and may be inconsistent with clean-up goals of the Leadville Drain and California Gulch Superfund projects. Existing classifications remain in place for all three segments. For segment 6, all numerical standards except fecal coliform have been deleted. No party objected to this change. For segments 2a and 2b, the Commission has adopted table value standards as the underlying numerical standards, with eight- year temporary modifications based on existing ambient quality. At the time that the original classifications and standards were adopted for segments 2a and 2b, in 1982, the Commission concluded that the prospects for future improvement of water quality were “too speculative” to adopt more-stringent-than-ambient water quality standards for these segments. Since then, the prospects for improvement have changed substantially. In view of the pending treatment of Leadville Tunnel water and the Superfund actions addressing California Gulch clean-up, the Commission now believes that it is appropriate to adopt table value standards for these segments, to serve as a goal for future clean-up, and protection from any new discharges.
There is some uncertainty at this time as to the precise metals levels that will be achieved instream following pending cleanup actions. The eight-year temporary modifications will not only allow time for substantial cleanup to occur, but will allow two triennial reviews to further assess the appropriateness of the underlying standards before they go into effect. If better information available in the future indicates that different underlying standards are appropriate, the standards can be modified at that time. As a matter of policy, the Commission does not believe that leaving ambient-quality-based standards in place as the sole standards for these segments at this time is appropriate, since that would suggest that the existing quality is acceptable for the future. That result would ignore the clean-up actions already planned and would be inconsistent with the Water Quality Control Act policy of improving water quality where necessary and reasonable.
F. Fountain Creek, Segment 2
1. AMAX, Inc.
2. ASARCO, Incorporated & Res ASARCO Joint Venture 3. CF&I Steel Corporation 4. Colorado Division of Wildlife 5. City of Colorado Springs, Water & Wastewater Divisions 6. Board of Water Works of Pueblo 7. City of Pueblo 8. City of Salida FINDINGS REGARDING BASIS FOR EMERGENCY RULE SEPTEMBER 11, 1990: The Commission held this emergency rulemaking hearing to readopt the classifications and numeric standards for one segment of the Arkansas River Basin to correct typographical errors in the original filing. The affected regulation was amended on June 5, 1990 and was filed within the required timeframes with the Secretary of State's Office and the Office of Legislative Legal Services. The Commission learned shortly after the filings that there was an error on page 12, segment 2, Fountain Creek of the tables.
The Commission finds that the immediate adoption of this regulation is imperatively necessary for the preservation of public health, safety, or welfare and that compliance with normal notice requirements would be contrary to the public interest. Emergency adoption is necessary to assure that the published regulation is consistent with the regulation that the commission adopted, to avoid confusion for the public and to assure that the revised discharge permit for the City of Colorado Springs is consistent with the Water Quality Control Commission's action.
32.16 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE; FEBRUARY,
The provisions of 25-8-202(1)(a), (b) and (2); 25-8-203; 25-8-204; and 25-8-402 C.R.S. provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted, in compliance with 24-4-103(4), C.R.S., the following statement of basis and purpose. Basis and Purpose:
(1) On June 5, 1990, following rulemaking hearings on November 6 and 7, 1989 and April 3, 1990, the Commission took final action to adopt numerous revisions to water quality classifications and standards throughout the Arkansas River Basin. On September 10, 1990 the Commission held an emergency rulemaking hearing to correct certain typographical errors in the revisions as filed following the June 5 action, specifically relating to segment 2 of Fountain Creek. To reflect the proper classifications and standards for this segment, the correction of these typographical errors has now been made permanent.
(2) Section 3.2.5(4) of this regulation contained provisions regarding a “footnote for un-ionized ammonia and nitrate.” The purpose of this section of the regulation was to implement a statutory provision that has subsequently been repealed. In addition, the footnotes provided for in this section had previously been deleted from the Arkansas Basin tables. Therefore, to conform with current law and avoid confusion, this section has been deleted.
(3) Section 3.2.6(3) has been revised to apply new zinc criteria as table value standards in the basin, in place of the table values set forth in Table III of the Basic Standards and Methodologies for Surface Water. The revised zinc criteria are based on new equations that have been determined to be more appropriate, and which have been developed since the Basic Standards and Methodologies for Surface Water were revised.
(4) A dissolved manganese standard of 50 ug/l was adopted for segment 2 of Fountain Creek even though the 85th percentile of representative data collected from Fountain Creek upstream of the Colorado Springs Wastewater Treatment Plant showed ambient levels of approximately 70 ug/l. This ambient level exceeds the 50 ug/l criterion contained in Table III of the Basic Standards which is meant to protect against objectional aesthetic qualities such as staining of laundry and taste problems in the finished water. Segment 2 was classified for water supply in 1980 based on its hydraulic connection to the Widefield Aquifer which is a major water supply for several municipalities and private residences. There were no surface withdrawals of water from segment 2 for domestic use in 1980 nor are there any at present or anticipated in the future. For these reasons and testimony from Colorado Springs that it is not feasible for their wastewater treatment plant to comply with either a 50 or 70 ug/l stream standard now or in the future, the Commission accepted the proposal that compliance with the standards would be based on maintaining a level below 50 ug/l at a point in the aquifer which should be most sensitive to changes in concentration caused by loadings to segment 2 of Fountain Creek.
1. City of Colorado Springs 2. Division of Wildlife 3. ASARCO Incorporated & RES-ASARCO Joint Venture FINDINGS REGARDING BASIS FOR EMERGENCY RULE FEBRUARY 5, 1991: The Commission held this emergency rulemaking hearing to revise the numerical standards for one segment of the Arkansas River Basin. Specifically, the dissolved manganese standard has been removed and other metals standards for Upper Arkansas segment 9 corrected, to reflect the fact that the water supply classification was previously removed from this segment. The Commission finds that the immediate adoption of this regulation is imperatively necessary for the preservation of public health, safety, or welfare and that compliance with normal notice requirements would be contrary to the public interest. Emergency adoption is necessary because the Commission previously removed the water supply classification from this segment and inadvertently did not correspondingly change the numerical standards, and because the ASARCO discharge permit for a discharge to this segment, which will be affected by these standards, expires in March of this year.
32.17 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE; AUGUST,
The provisions of 25-8-202(1), (b) and (2); 25-8-204; and 25-8-402 C.R.S. provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted, in compliance with 24-4-103(4), C.R.S., the following statement of basis and purpose. BASIS AND PURPOSE:
On February 5, 1991, the Commission held an emergency rulemaking hearing to revise the numerical standards for one segment of the Arkansas River Basin. Specifically, the dissolved manganese standard was removed and other metals standards for Upper Arkansas segment 9 corrected, to reflect the fact that the water supply classification was previously removed from this segment. Emergency adoption was deemed appropriate because the Commission previously removed the water supply classification from this segment and inadvertently did not correspondingly change the numerical standards. The factual basis for these revisions is unchanged and the Commission has therefore made them permanent. In addition, the Commission has added an expiration date for the temporary modifications for this segment. The intent of the Commission in adopting the date selected is that expiration correspond with the next triennial review of this segment, at which time it is anticipated that dissolved metals data will be available to set new standards consistent with the criteria of the basic standards. PARTIES TO THE AUGUST 5, 1991 RULEMAKING HEARING FOR THE UPPER ARKANSAS SEGMENT 9 ARKANSAS RIVER BASIN 1. Res-ASARCO Joint Venture
32.18 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE; NOVEMBER
The provisions of 25-8-202, 204; and 402 C.R.S., provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted, in compliance with 25-4-103(4), C.R.S., the following statement of basis and purpose.
BASIS AND PURPOSE:
The Commission adopted temporary modifications for Segment 1b as a result of its November 1989 hearing on the Arkansas River Basin. These temporary modifications are scheduled to expire December 31, 1992. A hearing for the Arkansas River Basin has been scheduled by the Commission for June 6, 1994. The Commission extended the expiration date of the temporary modification to December 31, 1994, so that the Commission will have an opportunity to hear evidence as to whether these temporary modifications continue to be necessary.
1. Climax Molybdenum Company 2. City of Arvada 3. Division of Wildlife 4. Hazardous Materials & Waste Management Division, Colorado Department of Health 5. City of Westminster
32.19 SPECIFIC STATUTORY AUTHORITY AND PURPOSE; MARCH 1, 1993 HEARING:
The provisions of 25-8-202(1)(a), (b) and (2); 25-8-203; 25-8-204; and 25-8-402 C.R.S. provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted in compliance with 24-4-103(4), C.R.S., the following statement of basis and purpose. BASIS AND PURPOSE:
The changes to the designation column eliminating the old High Quality 1 and 2 (HQ1, HQ2) designations, and replacing HQ1 with Outstanding Waters (OW) designation were made to reflect the new mandates of section 25-8-209 of the Colorado Water Quality Act which was amended by HB 92- 1200. The Commission believes that the immediate adoption of these changes and the proposals contained in the hearing notice is preferable to the alternative of waiting to adopt them in the individual basin hearings over the next three years. Adoption now should remove any potential for misinterpretation of the classifications and standards in the interim. In addition, the Commission made the following minor revisions to all basin segments to conform them to the most recent regulatory changes:
1. The glossary of abbreviations and symbols were out of date and have been replaced by an updated version in section 3.2.6(2).
2. The organic standards in the Basic Standards were amended in October, 1991, which was subsequent to the basin hearings. The existing table was based on pre-1991 organic standards and are out of date and no longer relevant. Deleting the existing table and referencing the Basic Standards will eliminate any confusion as to which standards are applicable.
3. The table value for ammonia and zinc in the Basic Standards was revised in October, 1991. The change to the latest table value will bring a consistency between the tables in the basin standards and Basic Standards.
4. The addition of acute un-ionized ammonia is meant to bring a consistency with all other standards that have both the acute and chronic values listed. The change in the chlorine standard is based on the adoption of new acute and chronic chlorine criteria in the Basic Standards in October, 1991.
Finally, the Commission confirms that in no case will any of the minor update changes described above change or override any segment-specific water quality standards.
32.20 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE: AUGUST 2,
The provisions of 25-8-202(1)(a), (b) and (2); 25-8-203; 25-8-204: and 25-8-402, C.R.S. provide the specific statutory authority for adoption of these regulation amendments. The Commission also adopted in compliance with 24-4-103(4), C.R.S., the following statement of basis and purpose. BASIS AND PURPOSE:
The Arkansas River mainstem segment temporary modifications (Segments 2a and 2b) were originally established to accommodate a Superfund cleanup schedule. The Iowa Gulch temporary modification (Segment 9) was to facilitate Asarco treatment process scheduling. Changes in the expiration dates for temporary modifications on these three segments were necessary to facilitate the scheduled rulemaking hearings for the Arkansas Basin without overextending the expiration date beyond the required three-year maximum. The basin hearing is scheduled for November, 1994. New data will likely be presented at that hearing which will result in either altered, new, or eliminated temporary modifications. Extending the current temporary modifications will accommodate that schedule without disrupting the regulatory decisions that are based on the current modifications.
32.21 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE:
The provisions of 25-8-202(1)(a), (b) and (2); 25-8-203; 25-8-204: and 25-8-402, C.R.S. provide the specific statutory authority for adoption of these regulation amendments. The Commission also adopted in compliance with 24-4-103(4), C.R.S., the following statement of basis and purpose. BASIS AND PURPOSE:
On November 30, 1991, revisions to “The Basic Standards and Methodologies for Surface Water” , 3.1.0 (5 CCR 1002-8), became effective. As part of the revisions, the averaging period for the selenium criterion to be applied as a standard to a drinking water supply classification was changed from a 1-day to a 30-day duration. The site-specific standards for selenium on drinking water supply segments were to be changed at the time of rulemaking for the particular basin. Only one river basin, the South Platte, has gone through basin-wide rulemaking since these revisions to the “Basic Standards” . Through an oversight, the selenium standards was not addressed in the rulemaking for this basin and has since become an issue in a wasteload allocation being developed for segments 15 and 16 of the South Platte. Agreement on the wasteloads for selenium is dependent upon a 30-day averaging period for selenium limits in the effected parties permits. Therefore, the parties requested that a rulemaking hearing be held for the South Platte Basin to addressing changing the designation of the 10 ug/l selenium standard on all water supply segments from a 1-day to a 30-day standard. The Water Quality Control Division, foreseeing the possibility of a selenium issue arising elsewhere in the state, made a counter proposal to have one hearing to change the designation for the selenium standard on all water supply segments statewide. The Commission and the parties concerned with South Platte segments 15 and 16 agreed that this would be the most judicious way to address the issue. The change in the averaging period may cause a slight increase in selenium loads to those segments which have CPDS permits regulating selenium on the basis of a water supply standard. However, these segments are only five in number and the use will still be fully protected on the basis that the selenium criterion is based on 1975 national interim primary drinking water regulations which assumed selenium to be a potential carcinogen. It has since been categorized as a non-carcinogen and new national primary drinking water regulations were promulgated in 1991 that raised the standard to 50 ug/l. The Commission also corrected a type error in the TVS for Silver by changing the sign on the exponent fro the chronic standards for Trout from + 10.51 to - 10.51.
32.22 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE: JUNE, 1994
The Commission has scheduled a rulemaking hearing to reconsider water quality classifications and standards throughout the Arkansas River Basin in April, 1995. For efficient utilization of resources, the Commission has extended the temporary modifications for four specific stream segments from December, 1994 to December, 1995, so that these temporary modifications can be considered along with other issues in the overall Arkansas Basin rulemaking hearing.
32.23 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE (1995 Silver
The provisions of C.R.S. 25-8-202(1)(b) and (2), and 25-8-204; provide the specific statutory authority for adoption of these regulatory amendments. The Commission adopted, in compliance with 25-4-103(4) C.R.S. the following statement of basis and purpose.
BASIS AND PURPOSE:
The changes described below are being adopted simultaneously for surface water in all Colorado river basins.
This action implements revisions to the Basic Standards and Methodologies for Surface Water adopted by the Commission in January, 1995. As part of a July, 1994 rulemaking hearing, the Commission considered the proposal of various parties to delete the chronic and chronic (trout) table values for silver in Table III of the Basic Standards. As a result of that hearing, the Commission found that the evidence demonstrated that ionic silver causes chronic toxicity to fish at levels below that established by the acute table values. It was undisputed that silver is present in Colorado streams and in the effluent of municipal and industrial dischargers in Colorado. The evidence also demonstrated that the removal of silver from wastewater can be costly. However, there was strongly conflicting scientific evidence regarding the degree to which silver does, or could in the absence of chronic standards, result in actual toxicity to aquatic life in Colorado surface waters. In particular, there was conflicting evidence regarding the degree to which the toxic effects of free silver are mitigated by reaction with soluble ligands to form less toxic compounds and by adsorption to particulates and sediments. The Commission concluded that there is a need for additional analysis of the potential chronic toxicity of silver in streams in Colorado. The Commission encouraged the participants in that hearing, and any other interested parties, to work together to develop additional information that will help resolve the differences in scientific opinions that were presented in the hearing. The Commission believes that it should be possible to develop such information within the next three years. In the meantime, the Commission decided as a matter of policy to take two actions. First, the chronic and chronic (trout) table values for silver have been repealed for the next three years. The Commission is now implementing this action by also repealing for the next three years, in this separate rulemaking hearing, all current chronic table value standards for silver previously established on surface waters in Colorado. Any acute silver standards and any site-specific silver standards not based on the chronic table values will remain in effect. The Commission intends that any discharge permits issued or renewed during this period will not include effluent limitations based on chronic table value standards, since such standards will not currently be in effect. In addition, at the request of any discharger, any such effluent limitations currently in permits should be deleted.
The second action taken by the Commission was the readoption of the chronic and chronic (trout) table values for silver, with a delayed effective date of three years from the effective date of final action. The Commission also is implementing this action by readopting chronic silver standards with a corresponding delayed effective date at the same time that such standards are deleted from the individual basins. The Commission has determined that this is an appropriate policy choice to encourage efforts to reduce or eliminate the current scientific uncertainty regarding in-stream silver toxicity, and to assure that Colorado aquatic life are protected from chronic silver toxicity if additional scientific information is not developed. If the current scientific uncertainty persists after three years, the Commission believes that it should be resolved by assuring protection of aquatic life.
In summary, in balancing the policy considerations resulting from the facts presented in the July 1994 rulemaking hearing and in this hearing, the Commission has chosen to provide relief for dischargers from the potential cost of treatment to meet chronic silver standards during the next three years, while also providing that such standards will again become effective after three years if additional scientific information does not shed further light on the need, or lack of need, for such standards. Finally, the Division notes that arsenic is listed as a TVS standard in all cases where the Water Supply classification is not present. This is misleading since Table III in the Basic Standards lists an acute aquatic life criterion of 360 ug/l and a chronic criterion of 150 ug/l for arsenic, but a more restrictive agriculture criterion of 100 ug/l. It would be clearer to the reader of the basin standards if, for each instance where the standard “As(ac/ch)=TVS” appears, the standard “As=100(Trec)” is being inserted as a replacement. This change should make it clear that the agriculture protection standard would prevail in those instances where the more restrictive water supply use protective standard (50 ug/l) was not appropriate because that classification was absent.
The chemical symbol for antimony (Sb) was inadvertently left out of the “Tables” section which precedes the list of segments in each set of basin standards. The correction of this oversight will aid the reader in understanding the content of the segment standards. Also preceding the list of segment standards in each basin is a table showing the Table Value Standards for aquatic life protection which are then referred to as “TVS” in the segment listings. For cadmium, two equations for an acute table value standard should be shown, one for all aquatic life, and one where trout are present. A third equation for chronic table value should also be listed. The order of these three equations should be revised to first list the acute equation, next the acute (trout) equation, followed by the chronic equation. This change will also aid the reader in understanding the intent of the Table Value Standards. PARTIES TO THE PUBLIC RULEMAKING HEARING JUNE 12, 1. Coors Brewing Company 2. The Silver Coalition 3. Cyprus Climax Metals Company 4. The City of Fort Collins 5. The City of Colorado Springs
32.24 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE: AUGUST 14,
The amendment to the Classifications and Numeric Standards for Arkansas River Basin, 3.2.0 (5 CCR 1002-8) are the result of the second in a series of comprehensive basin reviews of Colorado's stream classifications and standards. The Commission has established a schedule to continue these comprehensive reviews until all seven basins have undergone a thorough review using current data supplied through the Division's concentrated basin monitoring program, supplemented by USGS and other current data.
In the process of revising the classifications, designations, and standards for the Arkansas basin, the Commission relied heavily on the data and analysis supplied by the Division in its Exhibit 1. Where reference is made to the Division's recommendations in this statement, that reference is to Division Exhibit 1 unless specifically noted otherwise. Several parties to the hearing also supplied data and recommendations which the Commission used in arriving at a final set of classifications and standards and those sources are referenced as appropriate. The organization of this statement first addresses those general issues applicable to most or all segments, followed by a discussion of decisions applicable to individual segments.
GENERAL ISSUES:
1. Resegmentation : Extensive renumbering of segments was made throughout the basin due to information which showed that:
Rather than list here all the resegmentation that was made, the reader is advised to contact the Division if there are questions as to which streams are found in which segment descriptions.
2. Wetlands : In March, 1993, the Commission amended the Basic Standards and Methodologies for Surface Water 3.1.0 (5 CCR 1002-8) to include wetlands in the stream classification and standards system for the state. Due to that action, it became necessary to revise the segment description for all segments of the “all tributary” type to clarify that wetlands were also part of the tributary system for a given mainstem segment. All tributary wetlands now clearly carry the same classifications and standards as the stream to which they are tributary as provided for in 3.1.13(1) (e)(iv).
3. Conversion to Dissolved Metals : Several segments in the previous version of the classifications and standards contained standards for metals as “total recoverable” . The Commission previously determined that standards for most metals should be expressed as dissolved necessitating conversion of those metals for the following segments:
4. Changes Necessary to Comply with “Swimmable” Requirements : The Commission has reached an understanding with EPA regarding the classification and standards necessary to comply with the requirements contained in the federal Clean Water Act that all waters of the nation be suitable for recreation in and on the water. I n Colorado, that requirement translates into a Recreation, Class 1, with the 200 fecal coliform/100 ml standard wherever swimming, rafting, etc. are in place or have the potential to occur; Recreation, Class 2, with 200 FC/100 ml standard wherever secondary contact recreation only is practiced, and the existing quality supports a class 1 recreation use and little or no impact to dischargers will result; and Recreation, Class 2, with the 2000 FC/100 ml standard in most other situations. This policy has resulted in recreation classification and/or coliform standard modifications to the following segments: Upper Arkansas, segments 1b, 2a, 2b, 2c, 3, 5, 7, 8a, 8b, 9, 10, 11, 16b, 17b, 21, and 27. Middle Arkansas, segment 3.
The detailed rationale for these changes is found in WQCD Exhibit 1. A more complete basis and purpose for those segments where these changes were controversial is found in the segment-by-segment discussion which follows these general issues.
5. Upgrading of Class 2 Aquatic Life Segments : The Commission decided to adopted upgraded classifications and/or a more complete set of standards for several segments where the Division recommended same based on recent sampling of the biota by the Division of Wildlife (DOW) and the Water Quality Control Division. In general, these segments were previously thought to contain very little aquatic life, and were appropriate for the Class 2, minimal standards application found on most intermittent plains streams. However, the biological data referred to above indicated that a more diverse and rich aquatic life community existed, including threatened species. The Commission has chosen to recognize these facts by the adoption of a higher aquatic life classification and/or a complete set of protective standards. The streams so affected are:
6. Arsenic Standard : On all segments where arsenic was shown as “As(ac/ch)=TVS” , the Commission changed the standard to read “AS(ch)-100(Trec)” . This change was made because the Basic Standards (3.1.0) lists a lower Table Value Standard for agricultural use classification than the chronic aquatic life standard. Where water supply is a classified use, the Table Value Standard of 50 ug/l was retained since it was more restrictive.
7. Manganese Standard: On all segments classified for water supply and aquatic life uses, the total recoverable manganese standard of 1,000 ug/l was stricken. The aquatic life manganese criterion was changed in 1991 revisions to the Basic Standards from total recoverable to dissolved and on these segments a more stringent dissolved manganese water supply standard of 50 ug/l is in place.
8. Mercury Standard: The Basic Standards include the note that the standard for mercury is based on the Final Residual Value (FRV), and that mercury in the total form is the proper way to express that value. Therefore, the Commission decided to change the (TREC) notation for mercury to
9. Selenium Standard: The Commission revised the selenium water supply use criterion in the Basic Standards from 10 ug/l (Trec) to 50 ug/l (dis) in 1994. As a result, the chronic aquatic life criterion is now more stringent than the water supply value. In this action, the Commission decided to replace the old 10 ug/l standard with the TVS for aquatic life, namely “Se(ac/ch) = TVS” on all segments assigned a full set of standards for the protection of aquatic life.
10. Use Protected Designation: In a previous rulemaking, the Commission changed the basis for assigning the Use Protected designation by eliminating the automatic assignment where Recreation Class 2 was a classified use. In this comprehensive review of the Arkansas basin classifications, designations, and standards, the Commission revised several segment designations in order to be consistent with that Basic Standards revision. Those segments are: Middle Arkansas Segment 3; Arkansas River mainstem through Pueblo.
Lower Arkansas Segment 9a; Various small tributaries to the lower Arkansas River.
. Segment 13; Various reservoirs and ponds in the lower Arkansas basin.
11. Ambient-Based Standards : The Division presented extensive information in its Exhibit 1 regarding ambient chemical quality of many segments in the basin. In most cases ambient quality was well within the limits prescribed by the Basic Standards for the protection of the various classified uses, prompting the Commission to assign those Table value standards as segment standards. In a few cases, however, ambient quality exceeded the Table Values, yet there was information to suggest that the use was in place nonetheless. The available information lead to the conclusion that there was little hope of reversing the cause for degradation within twenty years. In those instances, the Commission followed the recommendation of the Division to adopt the 85th percentile of the ambient data as the standard (ambient-based standard). Division Exhibit 1 explains the basis for these ambient-based standards in detail, but the following is a list of those segments where such standards have been adopted:
Lower Arkansas, Segments 1 and 4.
12. Temporary Modifications : In several instances, the Commission decided to establish temporary modifications to Table Value Standards as an alternative to establishing an ambient-based standard. This practice was followed where these was information to suggest the underlying standard could be met within three years, or where there were questions surrounding the data which could be clarified with additional sampling. The segments where temporary modifications were established of modified are:
13. Full Standards Not Applied to Aquatic Life Segments : EPA raised the issue of why were the full set of inorganic aquatic life protection standards not applied to various segments recommended for aquatic life class 2 classification. These segments typically were assigned only dissolved oxygen, pH, and fecal coliform standards. It was EPA's position that if there were dischargers located on the segments with the potential to produce toxic levels of one or more of the pollutants not contained in the abbreviated list of standards, the aquatic life in the segment could be jeopardized. Rather than adopt the full set of inorganic standards, the Commission was persuaded by the Division's arguments in Exhibit 1 that the abbreviated list of standards was sufficient to protect the rudimentary aquatic life found in these intermittent streams, and that there was a very low probability that any of the few dischargers located on these segments would discharge toxic effluents. The segments where this policy was followed are: Upper Arkansas, Segments 14 and 26.
14. Water + Fish Organics Not Applied to Aquatic Life Segments : It is the policy of the Commission to establish the Water+Fish organics standards found in the Basic Standards for those Class 2 aquatic life segments where there is evidence that angling for edible species is at least occasionally practiced. No party, including the Division and Dow, produced such evidence at this hearing. Therefore, the Commission has chosen not to assign the Water+Fish organics to any of the Class 2 Aquatic life segments.
15. Ambient-Based Selenium Standards : The Commission decided to establish an ambient-based standard for selenium for Segment 2 of Fountain Creek and Segment 4 of the Lower Arkansas based on testimony of the Division in Exhibit 1. This action was taken with the understanding that the overall issue of the proper selenium standards for the state will be considered in an upcoming hearing, and that the proper methodology for establishing ambient-based selenium standards will also be a subject of that hearing. This action on two Arkansas basin segments is not intended to be definitive on the issue of selenium standards for the state, but rather, is merely a recognition of existing ambient conditions with respect to the current selenium Table Values.
16. Manganese Table Value for Agriculture Not Applied : EPA pointed out that the Commission has not proposed to include the Table Value for manganese of 200 ug/l for all segments in the Arkansas basin. The Commission was persuaded by the Division's arguments in its rebuttal statement that this table value was properly applied only to segments where site-specific information showed that acidic soils were under irrigation which might produce damaging levels of manganese. SEGMENT-SPECIFIC ISSUES and DECISIONS:
UA, Segment 1a, Waters in the Mount Massive and Collegiate Peaks Wilderness Areas: The Commission followed the recommendations of the Division in assigning the Outstanding Waters (OW) designation to all waters in these wilderness areas. Division data showed all antidegradation parameters to be well within Table Values and the wilderness waters provided habitat to ecologically significant specifies i.e. greenback cutthroat trout and the boreal toad. There was no opposition voiced by the parties or the public.
UA, Segment 1b, East Fork of the Arkansas River: Cyprus Climax Metals Company, a party to this hearing, and the Division resolved differences on this segment through the preparation of a stipulated agreement regarding Water Supply Classification, various standards, and the deletion and addition of various temporary modifications. The Commission concurred with the stipulation and adopted the contents as a result. The Division's rebuttal statement contains a full explanation of the basis for the stipulation.
UA, Segments 2b, 2c, 6, Upper mainstem of the Arkansas River; California, St. Kevin's Gulch: Although not objecting to the specific proposal of the Division, Resurrection Mining asked that certain language in the Division's Exhibit 1 be resided. The Commission declined to make such changes reasoning that the Division had the right to draw up its testimony (Exhibit 1) as it so chose, and that if there was misinformation or errors in that testimony, the Commission would prepare a separate rationale for the action it took on the particular segments in question. For the segments in question by Resurrection, the Commission has not found any reason to prepare a rationale different from that prepared by the Division. UA, Segment 3, Mainstem of the Arkansas River to Pueblo Reservoir: The Division of Wildlife asked that a pond (slough or oxbow lake) in Florence be separated out for classification to protect several important species which resided there. The Division testified that it considered that body of water part of Segment 3, the mainstem of the Arkansas, and would advise any regulatory program using the stream standards to base decisions affecting the pond on Segment 3 standards. With that understanding, the Commission decided not to separate out the pond, and rely on Division interpretation of Segment 3 description to protect the waterbody.
UA, Segments 19, 20, 21, and 22, Fourmile Creek, Cripple Creek, and Arequa Gulch: The Division, Cripple Creek and Victor Gold Mining (CC&V), agreed on segmentation, classification, temporary modifications, and standards for streams in the Cripple Creek area. “Citizens for Victor!” took a position that the standards should not be changed. Using the water quality data supplied by CC&V and commitments by CC&V to continue to monitor ambient quality, the Division and CC&V presented to the Commission a stipulated agreement on the segmentation, classifications, temporary modifications, and standards. Citizens for Victor! did not sign the stipulation. The Commission carefully considered the two positions and decided that because the TVS underlay the water quality parameters for which temporary modifications would expire and be reviewed in two years, the Division and CC&V proposal was the most appropriate in view of the uncertainties as to exactly how the water chemistry would change upon relocation of the tailings materials and the plans and commitments for operations and reclamation (through the mining and reclamation permit) of CC&V.
MA, Segment 3, Mainstem Arkansas River through Pueblo: The Division, City of Pueblo, Pueblo Waterworks, Pueblo West, and St. Charles Mesa all took various positions regarding the proper designation, recreation classification, aquatic life classification, and fecal coliform standard on the segment. Partial consensus was reached on the recreation classification, but the other issued remained for Commission decision. The Commission concluded that the proper designation was “reviewable” since the segment exhibited class 1 warm water characteristics and the quality was better than table values for all parameters. In addition, the Commission decided that 200 fecal coliforms/100 ml was appropriate since ambient quality met that level and no impact to dischargers would be felt with that standard in place. An additional factor in the coliform decision was the support that St. Charles Mesa had for the standard as additional protection for its water supply. The concerns from Pueblo and Pueblo West regarding possible financial impacts if the coliform standard and reviewable designation were adopted appeared speculative to the Commission.
MA, Segment 18, Warm Water Tributaries to the Arkansas River: Pueblo West took a position opposite that of the Division and DOW regarding the appropriateness of the aquatic life classification for the tributaries included in this segment. Pueblo West argued that not enough information was available to set the full set of standards recommended by the Division and Dow. The Commission felt there was sufficient rationale for the Division's recommendations, and adopted the classifications and standards accordingly. Dow asked that Rush Creek and Boggs Creek be included in Segment 18, and the Commission concurred.
FC, Segment 3, Tributaries to Fountain Creek on NF or USAF Lands: Colorado Springs asserted that the segment description as proposed by the Division was confusing and asked for clarification. After debating several alternatives for describing the segment, the Commission agreed upon a clarifying change.
FC, Segment 6, Monument Creek: The Division, Woodmoor, Donala, and USAF Academy had various positions regarding the appropriate recreation classification, coliform standard, and manganese standard for the mainstem of Monument below the National Forest boundary. As a result of meetings and conversations with the Division prior to the hearing, the parties decided not to oppose the Division's proposals for this segment. These parties intend to undertake additional monitoring to further assess the appropriateness of the standards for this segment. As a result, the Commission adopted the Division's recommendations as explained in Division Exhibit 1 for the segment. LA, Segment 1, Mainstem Arkansas River to Kansas Line: The City of Pueblo recommended that the fecal coliform standard remain at 2000 FC/100ml for segment 1 because it was protective of the actual recreation uses of the segment and because there was a potential for economic impact to the city through increased wastewater treatment costs. The Division recommended the standard be lowered to 200 FC/100ml because of the agreed upon approach to meeting the “swimmable” goals of the Clean Water Act, because the segment met the 200 coliform limit, and because Pueblo's treatment plant appeared to easily meet low coliform levels in its effluent. After considering the two positions, the Commission agreed with the Division's recommendations and adopted the 200 FC/100ml standard. The DOW asked that segment 1 (Fountain Creek to Kansas border) be resegmented at Nepesta, with a lowered ammonia standard of 0.06 mg/l (un-ionized) applied to the lower portion of the segment below Nepesta. Dow reasoned that several fish species in decline in the state were found in this reach, and that there was a correlation between high nutrient levels and the disappearance of these species elsewhere in the state. DOW also noted that the ambient levels of ammonia was consistently less than 0.06 mg/l unionized throughout the segment. The Division, City of pueblo, and CF&I Corporation disagreed with the DOW on the need for an ammonia standard lowered from the existing and proposed standard of 0.1 mg/l. They argued that DOW had not offered proof that ammonia was the cause for decline in these species anywhere, let alone in the lower Arkansas River and that a reduced ammonia standard could cause an economic impact on dischargers to that segment. The Commission shared the DOW's concern over the decline in certain native fish species in the state, but wanted further information regarding the cause for that decline before setting an ammonia standard which might cause financial hardship without clear benefit. Therefore, the Commission decided to continue with the 0.1 mg/l un- ionized ammonia standard with the understanding that in about one year, the Division and DOW would update the Commission on the status of the declining species and their sensitivity to ammonia, and on the true impacts to the dischargers on the segment. Based on the update, the Commission may at that time decide to reconsider the matter or continue with the 0.1 mg/l standard. PARTY STATUS LIST/MAILING LIST STATUS AUGUST 14, 1. The Cripple Creek & Victor Gold Mining Co.
2. Cyprus Climax Metals Co.
3. St. Charles Mesa Water District 4. The City of Pueblo 5. Resurrection Mining Co.
6. Colorado Division of Wildlife 7. City of Colorado Springs Water Resources Dept.
8. The Board of Water Works of Pueblo, Colorado 9. Pueblo West Metropolitan District 10. Citizens for Victor! 11. Woodmoor Water and Sanitation District 12. U.S. Environmental Protection Agency's Region VIII Office 13. CF&l Steel, L.P.
14. Donala Water and Sanitation District, Forest Lakes Metropolitan District and Triview Metropolitan District 15. Westplains Energy 16. Philip Voegtle
32.25 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; JULY, 1997
32.26 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE:
32.27 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE: FEBRUARY,
1. added a new segment 7 to Fountain Creek which includes only Willow Springs Pond #1 and Willow Springs Pond #2 and is classified as Aquatic Life Class 2 Warm, Recreation Class 2 and Agriculture with accompanying table value standards;
2. applied the Human Health Based Water + Fish standards for organic chemicals, including 0.8 micrograms per liter (µg/L) of tetrachloroethylene, also known as perchloroethylene (PCE), to this new segment 7 of Fountain Creek; and 3. applied a temporary modification of 2.0 µg/L PCE to Willow Springs Pond #1 with an expiration date of June 30, 1999.
The El Paso County Parks Department closed the Willow Springs Ponds to fishing on September 10, 1997 when it became aware that PCE was present in the tissue of two fish species from the ponds and in the water of the ponds. Large numbers of people fished in these ponds and for several years, the Colorado Division of Wildlife has stocked the ponds with fish as part of the “Fishing is Fun” program. Because segment 7 of Fountain Creek has been classified as Aquatic Life Class 2, and these ponds contain fish of a catchable size which are normally consumed by humans and where fishing takes place on a recurring basis, the Human Health Based Water + Fish Standards for organic chemicals, including the 0.8 µg/L standard for PCE, have been applied to segment 7 of Fountain Creek in this rulemaking. All parties to the rulemaking hearing before the Colorado Water Quality Control Commission, including El Paso County, Schlage Lock Company, the City of Colorado Springs and the Colorado Department of Public Health and Environment's Water Quality Control Division, stipulated to the classifications and standards described above.
In addition, these entities agreed that monitoring to assess compliance with the PCE standard will occur at the following points:
1. in Willow Springs Pond #1, at the approximate center of the pond, the average calculated for the water column consisting of, at a minimum, values from samples collected at the surface, 5 foot and 10 foot depths; and 2. in Willow Springs Pond #2, at the approximate center of the pond, one sample collected at the surface.
1. El Paso County Parks Department 2. City of Colorado Springs 3. Schlage Lock Company 4. Hazardous Materials and Waste Management Division
32.28 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE (September
The provisions of 25-8-202(1)(a) and (b), (2); 25-8-203; 25-8-204; and 25-8-402 C.R.S. provides the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted, in compliance with 24-4-103(4) C.R.S., the following Statement of Basis and Purpose. BASIS AND PURPOSE 1. Upper Arkansas Segment 1b - Temporary Modifications This segment previously had temporary modifications for manganese, lead and zinc which expired at the end of 1997. In this hearing, Climax Molybdenum Company proposed that ambient quality-based standards be adopted for these parameters on this segment. Based on the evidence presented to the Commission, the expired temporary modifications were reviewed and were readopted to March 31, 2002. This was done to accommodate TMDL studies that are underway on the segment, which the Commission understands will include an opportunity for participation by Climax Molybdenum Company.
2. Upper Arkansas Segments 2b and 2c - Temporary Modifications Upper Arkansas segments 2b and 2c had temporary modifications (Cd(ch) and Zn(ch) for 2b and Zn(ch) for 2c) that were due to expire at the end of 1998. The quality of water in these segments will be affected by the Superfund remediation efforts on California Gulch, which are not yet complete. Based on evidence presented to the Commission, the existing temporary modifications were extended until March 31, 2002. In addition, the Commission's action clarifies that underlying Zn(ac) standards = TVS will be in place for these segments, with a temporary modification of “no Zn(ac)” until March 31, 2002.
3. Upper Arkansas Segment 9 - Temporary Modifications This segment, which is the lower portion of Iowa Gulch, had a temporary modification for zinc that was due to expire at the end of 1998. Based on the evidence submitted, the Commission has adopted a revised temporary modification for “Zn(ac/ch) = existing quality, if determined less stringent than TVS” , with a March 31, 2002 expiration date. The adoption of the narrative temporary modification to the underlying zinc standards is in recognition that the only available dissolved zinc data for segment 9 at the time of the hearing was exclusively in the most downstream reach of the segment and may not be representative of the quality found throughout the segment. Dissolved zinc data collected in the late 80's and early 90's in segment 8b which is immediately upstream of segment 9 would tend to indicate that the zinc levels in the upstream portion of segment 9 could be significantly higher than the 85th percentile of the present available data and may exceed TVS values. It is understood that ASARCO, the operator of the Black Cloud Mine which discharges to segment 8b, will collect additional data from several points in segment 9 over the duration of the temporary modification. This should establish the existing quality in segment 9. The Commission hopes that this information will be useful in determining the appropriate standards for the segment.
4. Upper Arkansas Segments 21, 22a and 22b - Site-specific Standards Segment 22 has been divided into two segments, Arequa Gulch and Squaw Gulch. Arequa Gulch, Segment 22a, was previously classified by the Commission in 1995. At that time, the Commission adopted table value water quality standards and temporary modifications. This hearing was contemplated to review and revise the standards, as necessary. Arequa Gulch For this hearing, Cripple Creek and Victor Gold Mining Company (CC&V) proposed site-specific standards for Arequa Gulch based on application of 5 CCR 1002-31.7(1)(b)ii) Ambient Quality- Based Standards, and on 5 CCR 1002-31.7(1)(b)(iii) Site-Specific-Criteria-Based Standards. At the outset of the hearing, CC&V withdrew its proposed standards based on 5 CCR 1002-31.7(1) (b)(ii) in view of the Division's and EPA's general support for the proposed site-specific-criteria- based standards (with the exception of pH). CC&V emphasized that its election to withdraw the ambient quality-based standards proposal was not intended as an admission by CC&V that the water quality in Arequa Gulch is not natural or irreversible human-induced. The Commission is making no determination as to the “natural or irreversible human-induced quality” issue in this hearing.
The pH temporary modification recognizes existing water quality while holding out the possibility that these conditions may be correctable in the future if additional studies should demonstrate that a narrower pH range is necessary to protect aquatic life in Arequa Gulch. In the present circumstances, it appears that the appropriate first step toward “eliminating the need for the temporary modification” is completion of the additional studies. In view of the above, the Commission adopted the temporary modification for pH of 5.5 – 9.0 until November 30, 2000, which the Commission believes should provide adequate time to complete the anticipated studies, so that the issue of appropriate pH standards can be resolved. Citizens for Victor! also argued in this hearing that Arequa Gulch should be bifurcated into two segments, with more restrictive standards applying to the downstream reach. The Commission believes that the evidence submitted in this hearing is not adequate to warrant resegmentation of Arequa Gulch at this time. However, the Commission requests that additional information be developed regarding water quality in different reaches of Arequa Gulch, so that this issue regarding segmentation can be reviewed with better information in the future. Squaw Gulch Segment 22b is a new segment for Squaw Gulch from its source to the confluence with Cripple Creek. This segment is classified aquatic life cold 2, agriculture and recreation 2, and is designated use-protected. Because flow seldom exists in Squaw Gulch, only physical and biological standards have been adopted. This is consistent with the Commission's action in similar segments elsewhere in Colorado.
Cripple Creek (Segment 21)
The temporary modifications adopted in 1995 for iron and manganese for Cripple Creek, Segment 21, have been deleted.
5. Fountain Creek Segments 2a and 2b - Resegmentation and Adoption of Ambient Standards The mainstem of Fountain Creek from immediately above the confluence with Monument Creek to the confluence with the Arkansas River (formerly Segment 2) was bifurcated into the two segments described below upon analysis of water quality data that showed that differing ambient standards are appropriate for the two segments. The elevation of the water quality above table value standards for the parameters is due to natural and/or uncontrollable sources of pollutants. Fountain Creek Segment 2a - Mainstem of Fountain Creek from immediately above the confluence with Monument Creek to immediately above the confluence of Steele Hollow Creek. Ambient standards adopted: SO = 330 mg/l; Se(ch) = 6 ug/l; Fe(ch) = 8000 ug/l (which is the same as the previous iron standard for segment 2).
6. Lower Arkansas Segment 1a, 1b, and 1c - Resegmentation, Adoption of Ambient Standards and Deletion of Special Standards The mainstem of the Lower Arkansas River from immediately above the confluence with Fountain Creek to the Colorado/Kansas border (formerly Segment 1) was bifurcated into the three segments described below upon analysis of water quality data that showed that differing ambient standards are appropriate for the three segments. The elevation of the water quality above table value standards for the parameters is due to natural and/or uncontrollable sources of pollutants. Lower Arkansas Segment 1a - Mainstem of the Arkansas River from immediately above the confluence with Fountain Creek to immediately above the Colorado Canal headgate near Avondale, Colorado. Ambient standards adopted: S04 = 310 mg/l; Fe(ch) = 1900 ug/l (Trec); Se(ch) = 17 ug/l; Temporary Modifications for Se(ac), Se(ch) and S04= existing quality until 7/1/2008.
The Commission deleted section 32.5(5) which established site-specific dissolved oxygen (D.O.) standards for segment 1a. This action was taken because certain assumptions made for the justification of the standards in 1981 never materialized and a use attainability analysis (UAA) was not done which meets present day criteria. Because of concerns on the effects of the removal of the D.O. standards for segment 1a on the City of Pueblo whose wastewater treatment plant discharges to segment 1a, the Commission adopted a 3-year temporary modification to the 5 mg/l D.O. standards for segment 1a. It is anticipated that during the 3-year period, the City in consultation with the Division will develop a UAA that will provide information to the Commission at the next rulemaking hearing on the need for site-specific D.O. standards for segment 1a and, if needed, proposed standards.
7. Selenium Standards The Commission in 32.6(3) revised the table value standards (TVS) for selenium applicable to aquatic life segments in the Arkansas Basin to 20 ug/l acute and 5 ug/l chronic. This change reflects the TVS values in 31.16 of the “Basic Standards” which were adopted in October of 1995.
Fountain Creek Segment Se(ch) = 6 2a Fountain Creek Segment Se(ac) = 20 2b Lower Arkansas Segment Se(ch) = 17 ug/l, temp.
1a mod. of Se(ch) = “existing quality”
Lower Arkansas Segment Se(ch) = 16 1b Lower Arkansas Segment Se(ch) = 19 1c Lower Arkansas Segment Se(ac) = 20 Lower Arkansas Segment Se(ch) = 9
8. Manganese The Commission adopted an addition to section 32.6(3) to reflect the new table value aquatic life criteria for manganese. The aquatic life manganese criterion was changed in 1998 revisions to the Basic Standards from the 1,000 ug/l chronic to acute and chronic hardness based equations. On all segments with aquatic life uses with no water supply classification, the dissolved manganese standard of 1,000 ug/l was stricken and replaced with the acute and chronic aquatic life TVS.
9. Changes Necessary to Comply with “Swimmable” Requirements In continuation of the Commission's efforts comply with the federal Clean Water Act requirements that all waters of the nation be suitable for recreation in and on the water, two existing recreation class 2 waters for which recreational use was documented were upgraded to recreation class 1 and fecal coliform standards of 200 /ml were adopted. The waters upgraded are: Upper Arkansas segment 20 (Fourmile Creek) and Two Buttes Pond below Two Buttes Reservoir (moved from Lower Arkansas segment 9a to segment 10).
10. Water + Fish Organics Applied to Aquatic Life Segments It is the policy of the Commission to establish the water + fish organics standards found in the Basic Standards for those class 2 aquatic life segments where fish of a catchable size and which are normally consumed are present and there is evidence that angling takes place on a recurring basis. Based on these criteria and the testimony submitted, the Commission has chosen to assign the water + fish organics standards to the following class 2 aquatic life segments: Cimarron River segment 2 In addition, the Commission has added several lakes and reservoirs to existing class 1 segments which would afford them the protection of the water + fish standards. These waters were identified by the Colorado Division of Wildlife as public waters which are stocked with gamefish which are regularly caught and consumed. Most of these waters had previously been included under the all tributaries, lakes and reservoirs characterization of class 2 aquatic life segments that had the minimal set of standards. That classification and standards are intended to be applied to intermittent streams or reservoirs with only rudimentary aquatic life. The segments to which waters were added, and the waters are:
11. Full Standards Not Applied to Aquatic Life Segments The Commission reviewed information regarding aquatic life class 2 segments where the full set of inorganic aquatic life protection standards have not been applied. These are generally often dry segments with only rudimentary aquatic life. The Commission's policy has been that rather than adopt the full set of inorganic standards for these segments, standards for dissolved oxygen, pH and fecal coliform are protective. The Commission has upheld the previous decisions that there is a very low probability that any of the few dischargers located on these segments would discharge toxic effluents. The segments where this policy was followed are: Upper Arkansas Segment 14 Upper Arkansas Segment 26 Middle Arkansas Segment 4 Middle Arkansas Segment 15 Fountain Creek Segment 4 Lower Arkansas Segment 2 Lower Arkansas Segment 6b Cimarron River Segment 1 12. Ambient Quality-Based Standards The Commission reviewed information regarding use attainment on segments in the Arkansas River basin with standards less restrictive than the table value standards. The following segments were reviewed and the existing ambient standards were deemed appropriate all due to natural and/or man-induced irreversible causes:
Upper Arkansas Segment Mn (ch) = 99 Middle Arkansas Cd(ch) = 0.65 Segment 5 Middle Arkansas Cd(ch) = 0.85 Segment 7 Middle Arkansas Fe(ch) = 1100(Trec)
Segment 12 Lower Arkansas Segment Fe(ch) = 1200(Trec)
Lower Arkansas Segment Cd(ch) = 2 5a Lower Arkansas Segment Mn(ch) = 90 The Commission also instituted ambient standards on the following segments based on the determination that elevation of the water quality above table value standards for the parameters was due to natural and/or uncontrollable sources of pollutants. Fountain Creek Segment Se =6 2a Fountain Creek Segment S04 = 490, Fe(ch) = 2b 5100(Trec), Se(ac) =20 Lower Arkansas segment S04= 310, Fe(ch) = 1a 1900(Trec), Se(ch) =17 Lower Arkansas segment S04 = 1090, Fe(ch) = 1b 1900(Trec), Se(ch) =16 Lower Arkansas segment S04 = 2400, Mn(ch) = 1c 290(dis), Se(ch) =19 Lower Arkansas Segment Se(ac) = 20 Lower Arkansas Segment Se(ch) = 9 PARTY STATUSLIST STATUS FOR THE SEPTEMBER, 1998 RULEMAKING HEARING
1. Hazardous Materials and Waste Management Division 2. Resurrection Mining Company 3. Climax Molybdenum 4. Cripple Creek & Victor Gold Mining Company (CC&V)
5. Citizens for Victor! 6. ASARCO Incorporated 7. City of Colorado Springs 8. City of Pueblo 9. Board of Water Works of Pueblo, Colorado 10. U.S. Fish and Wildlife Service 11. Colorado Division of Wildlife 12. US EPA Region VIII
32.29 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE;
32.30 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE; FEBRUARY,
5.5 pH level is protective of aquatic life in Arequa Gulch.” Since the 1998 hearing, CC&V performed additional biological studies and a Whole Effluent Toxicity study. CC&V submitted the study results to the Division and to the parties to this hearing. The parties and the Division agreed to postpone the Commission hearing on this matter to the Arkansas River Basin triennial rulemaking hearing scheduled for November 12, 2001. In order to accommodate these objectives, the Commission extended the temporary modification to June 30, 2002 in order to give the Division, the parties, and CC&V additional time to evaluate the study results; give EPA additional time to consult with its Office of Research and Development; identify additional studies, if necessary; and implement such studies. PARTIES TO THE RULEMAKING HEARING 1. Cripple Creek and Victor Gold Mining Company 2. Sierra Club and Mineral Policy Center 3. U.S. EPA Region VIII
32.31 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE: MAY, 2001
BASIS AND PURPOSE As a result of a July, 2000 rulemaking hearing the Commission adopted numerous revisions to the Basic Standards and Methodologies for Surface Water, Regulation #31 (5 CCR 1002-31). These revisions included revisions to the table values in Tables II and III, which are intended to apply to site-specific waters in the various river basins wherever the Commission has adopted “table value standards” . In this current rulemaking, the Commission adopted revisions to section 32.6(3) of this regulation to conform with the revisions to the Basic Standards.
32.32 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY, AND PURPOSE:
Since the 1998 rulemaking, CC&V performed additional studies on Arequa Gulch including biological studies, a supplemental Use Attainability Analysis, and reviewed appropriate scientific literature. Based on the results of these studies and consideration of appropriate scientific literature, CC&V proposed to replace the existing temporary modification of 5.5 to 9.0 and underlying standard of 6.5 to 9.0 for pH in Arequa Gulch, and to add a site-specific standard of 5.5 to 9.0. Based on its review of the CC&V studies and scientific literature, the Division recommended an alternative proposal of removing the existing temporary modification and underlying standard, and adding a permanent site-specific standard of 6.0 to 9.0 with a new temporary modification of 5.6 to 9.0 that will be effective until December 31, 2007. This alternate proposal was accepted by CC&V. The Division's proposal for a new underlying standard of 6.0 to 9.0 was based upon the last 3 years of pH data because they have remained relatively constant over this period of time. The lower15th percentile of these data showed a value of 6.06 . Further, the Division's review of the scientific literature show that a pH of 6.0 to 9.0 would be protective of pH-sensitive species that would be expected to be found in Arequa Gulch. [Basic Standards, §31.7(1)(b)(iii)]. The Division's proposal for a temporary modification of 5.6 to 9.0 was based upon the lowest observed value in the last 3 years of data (5.6) and was intended to allow time to determine if the trend of improving pH will continue and thus resolve any uncertainty about the appropriateness of the underlying standard. [Basic Standards, §31.7(3)].
The Commission adopted the Division's alternative proposal and requested that CC&V continue its monitoring efforts during the term of the temporary modification. If, during this time the pH conditions in Arequa Gulch do not improve or show a declining trend, a rulemaking hearing to re-evaluate the temporary modification may be requested. CC&V committed to continue its efforts with regard to its operation of an experimental passive treatment system in Arequa Gulch at the upcoming Arkansas River basin-wide hearing in July of 2002.
1. Cripple Creek & Victor Gold Mining Company 2. Sierra Club and Mineral Policy Center 3. U.S. Environmental Protection Agency's Region VIII
32.33 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE, DECEMBER,
BASIS AND PURPOSE In the spring of 2001, the Commission established a new schedule for major rulemaking hearings for each of its water quality classifications and standards regulations, as part of the triennial review process. As part of the transition to this new schedule, in order to facilitate an efficient and coordinated review of all water quality standards issues in this basin, in this hearing the Commission decided to extend the existing temporary modifications of water quality standards previously adopted for segments in this basin, so that such temporary modifications will not expire prior to the next scheduled major rulemaking hearing for this basin. the Commission decided to extend the existing temporary modifications of water quality standards previously adopted for segments in this basin, so that such temporary modifications will not expire prior to the next scheduled major rulemaking hearing for this basin.
32.34 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; JULY, 2002
A. Resegmentation Some renumbering and/or creation of new segments was made in the basin due to information which showed that: a) the original reasons for segmentation no longer applied; b) new water quality data showed that streams should be resegmented based on changes in their water quality; and/or c) certain segments could be grouped together in one segment because they had similar quality and uses. The following changes were made: Upper Arkansas segment Chalk Creek 12a:
Middle Arkansas segment Rock, Salt and Peck 4b: Creeks from Middle Arkansas segment 4d Middle Arkansas segment Chico Creek and 4c: tributaries from Middle Arkansas segment 4d Middle Arkansas segment Graneros and North 7: Muddy Creeks from Middle Arkansas 4d Middle Arkansas segment Turkey Creek from 11: Lower Arkansas 2 Middle Arkansas segment North Apache Creek from 17: Lower Arkansas 2 Middle Arkansas segment Boggs Creek 18a:
Fountain Creek segments Segment boundary moved 2a, 2b: from Steele Hollow Creek to “a point immediately above the Highway 47 Bridge”
Fountain Creek segments Divide former segment 7 7a, 7b: into 7a and 7b Lower Arkansas 3b: Dry tributaries from Lower Arkansas 3a Lower Arkansas 4: Lorencito Canyon from Lower Arkansas segment Lower Arkansas segment Lake Dorothey from 5b: Lower Arkansas 2 Lower Arkansas 9a: Cheyenne Creek, Buffalo Creek from Lower Arkansas 9b Lower Arkansas 13: Ramah Reservoir from Lower Arkansas 2
B. Selenium The Commission adopted table value standards for selenium and temporary modification of existing ambient quality for selenium for Middle Arkansas segments 2, 3, 4a, 5, 10, 12, and 18a Fountain Creek segments 2b and 6 Lower Arkansas segment 1a, 1b, 1c, 3a, 4, 7, 9a, 9c, and 11 The temporary modifications were adopted pursuant to section 31.7(3)(a)(iii) of the Basic Standards regulation, based on the fact that there is significant uncertainty as to the appropriate underlying selenium standard for these segments.
C. Recreation Classifications/Fecal Coliform and E. Coli Standards The biological standards were updated to include the dual standards for E. coli and fecal coliform, which were adopted by the Commission in the 2000 revisions to the Basic Standards. As stated in the statement of basis and purpose for the Basic Standards revisions, the Commission intends that dischargers will have the option of either parameter being used in establishing effluent limitations in discharge permits. In making section 303(d) listing decisions, in the event of a conflict between fecal coliform and E. coli data, the E. coli data will govern. The Commission believes that these provisions will help ease the transition from fecal coliform to E. coli standards. In a continuation of the Commission's efforts to comply with the requirements contained in the federal Clean Water Act that all waters of the nation should be suitable for recreation in and on the water (known as the “swimmable” goal), the Commission reviewed all Recreation Class 2 segments. In Colorado, the “swimmable” goal translates into Recreation Class 1a, with the 200/100 ml fecal coliform and 126/100 ml E. Coli standard, and Class 1b with the 325/100 ml fecal coliform and 205/100 ml E. coli standard. Class 1a indicates waters where primary contact uses have been documented or are presumed to be present. Class 1b indicates waters where no use attainability analysis has been performed demonstrating that a recreation class 2 classification is appropriate. To maintain the existing Recreation Class 2 with the 2000/100 ml standard on a segment, it must be shown that there is minimal chance that a Recreation Class 1 activity could exist (e.g. ephemeral or small streams that have insufficient depth to support any type of Recreation Class 1 use or very restricted access). A recreation class 1a classification of a segment is not intended to imply that the owner or operator of property surrounding and waterbody in a segment would allow access for primary contact recreation. The application of recreation classifications to state waters pursuant to these provisions does not create any rights of access on or across private property for the purposes of recreation in or on such waters. A recreation class 1a classification is intended to only affect the use classification and water quality standards of a segment, and does not imply public or recreational access to waters with restricted access within a segment. For segments changing to recreation Class 1a because no information was available about actual recreational uses, the last paragraph of section 31.6(2)(b) will apply to future changes to the recreation classification where a proper showing is made through a use attainability analysis that a recreation Class 2 classification is appropriate, without application of the other downgrading criteria in this section. Moreover, the Commission is relying in part on the testimony from EPA that completion of a use attainability analysis showing that a lower recreation classification is appropriate satisfies applicable downgrading criteria. Based on these factor, the Commission intends that in a future rulemaking hearing, the test for adopting a recreation Class 2 classification would be the same as if it had been considered in this hearing The following segments with existing Recreation Class 1 classifications were changed to Class 1a:
Fountain Creek segment 7a The following segments retained their Recreation Class 2 classification with 2,000/100mL fecal coliform and 630/100 ml E. coli standard after sufficient evidence was received that a Recreation Class 1a or 1b use was unattainable.
Upper Arkansas segments 6, 22a and 22b Fountain Creek segment 5 Lower Arkansas segment 2 and 3b Cimarron segment 1
D. Aquatic Life Segments without Full Standards The Commission reviewed information regarding Aquatic Life Class 2 segments where the full set of inorganic aquatic life protection standards have not been applied. Generally, these are dry segments with only rudimentary aquatic life. The Commission's policy has been that rather than adopt the full set of inorganic standards for these segments, standards for dissolved oxygen, pH and fecal coliform provide sufficient protection.
E. Revised Aquatic Life Use Classifications The Commission reviewed information regarding existing aquatic communities. The following segment's aquatic life classifications were upgraded from aquatic life class 2 to aquatic life class 1 based on information presented that showed diverse aquatic communities in these segments. Middle Arkansas segment 4c Lower Arkansas segment 7 F. Ambient Quality-Based Standards There are several segments in the Arkansas River Basin that contain ambient standards. Ambient standards are adopted where natural or irreversible man-induced conditions result in water quality levels higher than table value standards. EPA had requested that the Commission review the information that is the basis for these standards as well as any new information that would indicate whether they are still appropriate, need to be modified, or should be dropped. The Division reviewed the information about ambient water quality levels and provided testimony that justified revising the ambient standards on the following segments: Upper Arkansas segment 8b: Zn(ch)
Fountain Creek segment 2a: SO , Fe(ch), Se(ch)
Fountain Creek segment 2b: Fe(ch), SO Fountain Creek segment 6: Fe(ch)
Lower Arkansas segment 1a: Fe(ch), SO Lower Arkansas segment 1b: Fe(ch), SO Lower Arkansas segment 1c: Mn(ch), SO Lower Arkansas segment 4: Fe(ch)
Lower Arkansas segment 11: Mn(ch)
Ambient standards were removed from the following segments due to new data and/or changes to the basic standards which indicated ambient standards were no longer appropriate: Middle Arkansas segment 5: Cd(ch) and Zn(ch)
Middle Arkansas segment 12: Fe(ch)
Fountain Creek segment 6: Mn(ch)
Lower Arkansas segment 5a: Cd(ch)
G. Temporary Modifications There were several segments where temporary modifications that reflect current ambient conditions were adopted or retained. Temporary modifications were set to expire on 12/31/07 to coincide with the next triennial review. The segments and the constituents are: Upper Arkansas segment 1b: Pb(ch), Zn(ch)
Upper Arkansas segment 5: Zn(ch)
Upper Arkansas segment 7: Zn(ch)
Upper Arkansas segment 22a: pH Middle Arkansas segment 10: Zn(ch)
Middle Arkansas segment 13: F. Coli Middle Arkansas segment 18a: Zn(ch)
Fountain Creek segment 1: F. Coli Lower Arkansas segment 1a: SO Lower Arkansas segment 3: Fe(ch)
Lower Arkansas segment 9c: Fe(ch)
The Commission rejected an argument by Colorado Springs that the fecal coliform temporary modification for Fountain Creek segment 1 should be specified as based on uncertainty. An additional list of segments with temporary modifications for selenium can be found at section B, above.
H. Organic Standards The organic standards were updated to include changes adopted by the Commission in the 2000 revisions to the Basic Standards (see 31.11 in Regulation No. 31). “Water + Fish” organic standards are presumptively applied to all Aquatic Life Class 1 streams which also have a Water Supply classification, and are applied to Aquatic Life Class 2 streams which also have a Water Supply classification, on a case-by-case basis. The “Fish Ingestion” organic standards are presumptively applied to all Aquatic Life Class 1 streams which do not have a Water Supply classification, and are applied to aquatic life class 2 streams which do not have a Water Supply classification, on a case-by-case basis.
I. Water Supply Classification These segments had the Water Supply classification added to them. The associated water supply standards will now apply to segments:
J. Modification of Water Supply Standards Water supply standards were modified to conform to the changes made by the Commission in the 2000 revisions to the Basic Standards (see Regulation No. 31 at 31.11(6)). The Commission modified the water supply standards for iron, manganese, and sulfate that are based on secondary drinking water standards (based on esthetics as opposed to human-health risks). The numeric values in the tables were changed to Fe(ch) = WS (dis), Mn(ch) = WS (dis), and SO =
K. Agriculture Standards Numeric Standards to protect Agricultural Uses were adopted for the following segments: Upper Arkansas segments 14b Middle Arkansas segments 4d, and 15 Fountain Creek segment 4 Lower Arkansas segments 2, 3a and 6 Cimarron segment 1 Numeric standards to protect livestock watering were adopted for the following segment: Upper Arkansas segment 22b L. Other Site-Specific Revisions The Commission corrected several typographical and spelling errors, and clarified segment descriptions.
For zinc, the Commission has adopted a new chronic standard of 600 ug/l, based on the 85th percentile of the last five years of available data, to replace the previous ambient-quality based standard. The Commission chose to base the zinc standard on the last five years of data, rather than on the three-year period recommended by the Division, due to uncertainty as to the factors influencing ambient metals concentrations in Arequa Gulch over the last few years, and because a five-year period of record has most commonly been used when assessing the current ambient quality of a water body. Because there was no new zinc toxicity data available, no proposal was submitted in this hearing by Cripple Creek & Victor Gold Mining Company regarding use of a recalculation procedure to derive a zinc standard. Therefore, the Commission has made no changes to the previous recalculation based acute zinc standard adopted in 1998. Fountain Creek segments 2a and 2b : On both segments, the Division proposed to adopt underlying table value standards with temporary modifications based on existing ambient quality. In response, Colorado Springs proposed to adopt standards based on existing ambient quality. In its rebuttal, the Division of Wildlife proposed moving the boundary between segments 2a and 2b further south to Highway 47 because selenium concentrations increase below this point. The Commission concurs in this resegmentation as more representative of the water quality in this portion of Fountain Creek.
The Commission set an ambient standard for selenium of 8 µg/l for segment 2a. The EPA has previously approved an ambient standard for the former segment 2a. In regards to segment 2b, the Commission established a temporary modification based on uncertainty of 23 µg/l, with an underlying table value standard. Other standards for these segments remain unchanged. Fountain Creek segment 3 : The selenium standard was corrected. Fountain Creek segment 7 : This segment consisted of six lakes. The Division proposed that all lakes in the segment receive a classification of water supply and that the recreational use classification be upgraded from class 2 to 1a.
Colorado Springs opposed the recreation class 1a classification for Pikeview Reservoir and submitted a use attainability analysis to support retaining the class 2 classification. Similarly, El Paso County opposed the recreation class 1a classification for the Willow Springs Ponds. The Division and EPA agreed that there is no existing primary contact recreation for these lakes, but believed that there is a potential for primary contact. They recommended a recreation class 1b classification, which was adopted by the Commission. Pikeview Reservoir and the Willow Springs Ponds are now resegmented as segment 7a.
Colorado Springs provided testimony that Prospect and Quail Lakes are not currently used, or anticipated to be used in the future, as a source of domestic water supply. Similar evidence was submitted by the Division for Monument Lake. Therefore, the “fish ingestion” organics standards, rather than “water + fish” standards, appropriately apply to these lakes, which are now resegmented as segment 7b.
Lower Arkansas segment 1a : The site specific dissolved oxygen standard was removed. This standard became unnecessary because of the recently adopted mixing zone policy. Lower Arkansas segment 3a : The Commission determined that the tributaries identified in the Cedar Ridge proposal are significantly different from the physical characteristics of the mainstem of the Apishapa River. As a result, the Commission created a new segment to more accurately reflect the significant changes in use, physical characteristics and water quality characteristics between the dry tributaries and the mainstem of the Apishapa River in the vicinity of Aguilar, Colorado. The new segment is entitled Segment 3a of the Lower Arkansas Basin. The Commission assigned the classifications of aquatic life class 2, water supply, recreation and agriculture and applied appropriate standards to this new segment. PARTIES/MAILING LIST STATUS FOR JULY, 2002 RULEMAKING HEARING
1. El Paso County 2. City of Colorado Springs 3. Colorado Division of Wildlife 4. Cedar Ridge, L.L.C.
5. Climax Molybdenum Company 6. The Cripple Creek & Victor Gold Mining Company 7. City of La Junta 8. ASARCO Incorporated 9. The City of Pueblo 10. Resurrection Mining Company 11. Pikes Peak Area Council of Governments 12. The City of Aurora, Colorado acting by and through its Utility Enterprise 13. Sierra Club and Mineral Policy Center 14. U.S. EPA Region VIII
32.35 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; FEBRUARY,
Site Specific Issues :
Lower Arkansas segment 1a : Lower Arkansas Segment 1a currently has temporary modifications for selenium and sulfate that are based on existing water quality. In the 2002 RMH, only selenium was adopted based on uncertainty despite the fact that the source of both of these parameters were shown to be of the same source and to be occurring for natural reasons as proposed by the City of Pueblo in the 1998 rulemaking hearing. The Commission adopted the sulfate temporary modification based on uncertainty to be consistent with the selenium temporary modification. Lower Arkansas segment 2b : The Commission subdivided Segment 2 of the Lower Arkansas River into 2 segments placing King Arroyo into Segment 2b.
The City of La Junta expressed concerns about the application of numeric agricultural standards during the triennial review in July, 2002; but could not object, having certain knowledge that livestock drink from the Arroyo. However, the City did not realize that a separate set of standards could be established for livestock watering when crop irrigation did not take place. The urgency for a site-specific review related to the timing of the City's NPDES permit expiration and renewal process in 2003. The City's permit (effective January, 1999) had limits protective of the Lower Arkansas River based on the stream standards for Segment 1b. The City's permit was also based on King Arroyo standards if those standards were more stringent. The City believed that application of crop-irrigation standards on King Arroyo had high potential for requiring significant additional wastewater treatment for a non-existent use. Nothing in this proposal was intended to change the application of Lower Arkansas River, Segment 1b in the City's discharge permit nor to provide relief to the City for meeting any other standards based on established uses. The application of livestock-watering-only standards on King Arroyo provided sufficient protection for its established uses without unnecessarily causing more stringent limitations in the City's permit.
Since there are water bodies within segment 2 used for crop irrigation, King Arroyo is not one of them. The Commission has left those waterbodies in segment 2a and created a new segment 2b for King Arroyo to classify this segment as Agricultural Use - Livestock Water only. District 17 Water Commissioner, Don Taylor, provided a statement to this effect. Lower Arkansas Segments 3b and 3c : The Commission determined that certain tributaries in Segment 3a—Frio Canyon Creek, Borrego Canyon Creek, Munoz Canyon Creek, Williams Canyon Creek, and Castro Canyon Creek, including all tributaries, from their sources to their confluences with the Apishapa River - were not in the appropriate segment. Specifically, the Commission determined that the use, physical characteristics and water quality characteristics of these tributaries are significantly different from those of the mainstem of the Apishapa River. As a result, the Commission moved these tributaries to Segment 3b to more accurately reflect the significant changes in use, physical characteristics and water quality characteristics between the dry tributaries and the mainstem of the Apishapa River in the vicinity of Aguilar and Gulnare, Colorado. Additionally, the Commission determined that Jarosa Canyon Creek and Rito Seco (a tributary to Jarosa Canyon Creek) did not have the same use, physical characteristics and water quality characteristics as the mainstem of the Apishapa in Segment 3a or the dry tributaries in Segment 3b. Therefore, the Commission created a new segment, Segment 3c, to contain Jarosa Canyon Creek, including all tributaries, from the source to the confluence with the Apishapa River. The Commission assigned to Segment 3c the classifications of aquatic life cold class 2, water supply, recreation 1a and agriculture and applied appropriate standards. PARTIES TO THE RULEMAKING HEARING 1. Evergreen Operating Corporation 2. City of La Junta 3. Cedar Ridge, L.L.C 4. Colorado Division of Wildlife 5. El Paso County
32.36 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; NOVEMBER,
This temporary modification is based upon uncertainty regarding the appropriateness of the underlying standard, specifically the level of water quality necessary to protect aquatic life. Increased copper discharges from the WWTF have necessitated investigation into both the sources of copper in the Tri- Lakes system and the appropriateness of the standard. Tri-Lakes will continue its investigation including source control, water effect ratios and biotic ligand modeling to determine an appropriate WER. Consistent with the sampling plan for quarterly and monthly data collection, the seasonal aspects of potential copper toxicity and the downstream extent of the WER will also be explored. The study will be completed in time for the basin-wide Issues Formulation Hearing in November 2006. If the study is completed before that time, a hearing may be requested before the basin-wide hearing. PARTIES/MAILING LIST STATUS FOR NOVEMBER, 2004 RULEMAKING HEARING 1. Tri-Lakes Joint Use Wastewater Treatment Facility 2. Colorado Division of Wildlife
32.37 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; DECEMBER
32.38 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE: January
BASIS AND PURPOSE:
The Commission revised the basin-wide temperature standards as part of the 2007 rulemaking hearing. These changes clarify the numeric temperature standards that will be in effect until the basin-wide rulemaking hearing in June of 2012. At that time, the Commission intends to consider segment specific temperature standards for all segments with aquatic life uses. The Commission applied 17 ° C as an interim chronic standard for small, high elevation streams that are likely to be habitat for brook trout and cutthroat trout. First, second and third order streams are defined at section 31.5 in the Basic Standards.
For the remainder of the cold water segments, the Commission left the current 20 ° C in place as an interim standard with the clarification that it is a chronic standard. The existing 30 ° C criterion for warm water segments was left in place as an interim standard with the clarification that is also to be applied as a chronic standard.
1. The Temperature Group (City of Aurora, City of Boulder, Colorado Springs Utilities, Littleton/Englewood Wastewater Treatment, The Metro Wastewater Reclamation District, Colorado Mining Association, Colorado Rock Products Association, Tri-State Generation & Transmission Assn., Xcel Energy, Denver Water, Northern Colorado Water Conservancy District, Southeastern Colorado Water Conservancy District)
2. City of Grand Junction 3. City of Loveland 4. City of Pueblo 5. Metro Wastewater Reclamation District 6. City of Aurora 7. City of Boulder 8. Colorado River Water Conservation District 9. Colorado Wastewater Utility Council 10. Bear Creek Watershed Association 11. Chatfield Watershed Authority 12. Mountain Coal Company, L.L.C.
13. Northern Colorado Water Conservancy District 14. Colorado Rock Products Association 15. Littleton/Englewood Wastewater Treatment Plant 16. Northwest Colorado Council of Governments 17. Southeastern Colorado Water Conservancy District 18. Colorado Mining Association 19. Colorado Division of Wildlife 20. South Platte Coalition for Urban River Evaluation 21. City and County of Denver 22. City of Colorado Springs and Colorado Springs Utilities 23. City of Westminster 24. Board of Water Works of Pueblo 25. Coors Brewing Company 26. City and County of Broomfield 27. Centennial Water and Sanitation District 28. Plum Creek Wastewater Authority 29. Climax Molybdenum Company 30. Cripple Creek & Victor Gold Mining Company 31. Tri-State Generation and Transmission Association 32. Xcel Energy 33. Sky Ranch Metropolitan District No. 2 34. Parker Water and Sanitation District 35. CAM-Colorado and CAM Mining LLC 36. Aggregate Industries – WCR, Inc.
37. Grand County Water and Sanitation District #1, Winter Park Water and Sanitation District, Winter Park West Water and Sanitation District and Fraser Sanitation District 38. Trout Unlimited and Colorado Trout Unlimited 39. Colorado Contractors Association 40. United States Environmental Protection Agency, Region 8 41. Hot Springs Lodge and Pool 42. Denver Regional Council of Governments
32.39 STATEMENT OF BASIN SPECIFIC STATUTORY AUTHORITY AND PURPOSE MARCH 2007
At the June 2005 Basic Standards rulemaking, the Commission adopted the 1999 Update of Ambient Water Quality Criteria for Ammonia (US EPA, Office of Water, EPA-822-R-99-014, December 1999) as the numeric ammonia criteria for Colorado. These new criteria are in the form of total ammonia rather than un-ionized ammonia. The Commission modified the ammonia equations in 35.6(3) and footnotes to conform to Regulation # 31.
Consistent with the approach outlined in the Basic Standards statement of basis and purpose, the Commission provided flexibility for dischargers faced with the possibility of new, more stringent effluent limits.
Temporary modifications were generally set to expire on 12/31/11. This date is set far enough in the future to allow facilities to consider their specific circumstances and to develop a plan regarding how to proceed, yet soon enough to assure that facilities are making progress in developing facility plans. For those that feel the underlying standards are inappropriate, time is allowed to study the receiving water and develop a proposal for an alternate standard. For those that need time to plan, finance or construct new facilities, time is allowed to develop that facility improvement plan. The intent of the Commission is that in general, the permits for dischargers to warm water segments, that need time to achieve compliance, will contain schedules of compliance in the next renewal. The Commission understands that such a compliance schedule may include time to complete necessary sub- tasks or milestones. For example, this might include time to do facility planning, make financing arrangements, pre-design, design, construction, startup and commissioning. There are several opportunities to revisit the duration of the temporary modifications before they expire on 12/31/2011. For those segments in the Upper and Lower Colorado Basins (Regulations # 33 and 37), persons can come forward at the Issues Formulation hearing in November 2007 with their intent to seek a site-specific adjustment in the June 2008 hearing. For those segments in the South Platte Basin (Regulation # 38), persons can come forward at the Issues Formulation hearing in November 2008 with their intent to seek a site-specific adjustment in the June 2009 hearing. In addition, all of these temporary modifications will be subject to the Annual Temporary Review process which will have hearings in December 2009 and 2010.
The Commission intends that the temporary modifications adopted in this rulemaking are “type i” temporary modifications, with specific exceptions where a demonstration was made that there is uncertainty regarding the appropriateness of the underlying standard. The Commission has adopted “type iii” temporary modifications for Middle Arkansas, segment 4c with an expiration date of 12/31/11.
The issues raised in this rulemaking hearing have highlighted the need to clarify the relationship between the temporary modification tool and the compliance schedule tool in Colorado’s water quality management program. The Commission requests that the Division consider this issue further, with input from interested stakeholders, and bring forth any suggested revisions/clarifications for the 2010 Basic Standards rulemaking.
In the meantime, because of the Commission’s previously expressed concerns regarding the unique and widespread challenges associated with compliance with the new ammonia standards, the Commission’s intent with respect to temporary modifications and compliance schedules regarding these new ammonia standards is as follows:
- Where a demonstration has been made that a period of time longer than the end of 2011 will be required for compliance with the new ammonia standards, the Commission has approved an appropriate site-specific temporary modification expiration date. - For segments where the 12/31/11 expiration date applies, and for which discharge permit renewals may be issued prior to that date, it is the Commission’s intent, consistent with section 31.14(15) (a), that the Division have the authority to issue compliance schedules that may not result in full attainment of the ammonia standard prior to expiration of the renewal permit. Such compliance schedules should be issued only where the Division determines that a specific demonstration has been made that additional time is needed to attain the standard. In such cases, the Commission anticipates that permits would include milestones that assure reasonable progress toward attainment of the standard.
1. Boxelder Sanitation District 2. Estes Park Sanitation District 3. City of Pueblo 4. The City of Boulder 5. The Metro Wastewater Reclamation District 6. The Colorado Wastewater Utility Council 7. The Paint Brush Hills Metropolitan District 8. The Grand County Water & Sanitation District #1, the Winter Park West Water & Sanitation District, the Fraser Sanitation District and the Winter Park Water & Sanitation District 9. Mountain Water & Sanitation District 10. The Town of Gypsum 11. The City of Grand Junction 12. City and County of Broomfield 13. Centennial Water & Sanitation District 14. Town of Erie 15. The City of Fort Collins 16. Plum Creek Wastewater Authority 17. The City of Sterling 18. Eastern Adams County Metropolitan District 19. The City of Littleton 20. Two River Metro District 21. H Lazy F Mobile Home Park 22. Rock Gardens Mobile Home 23. Blue Creek Ranch 24. The City of Greeley 25. US EPA
32.40 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; JUNE 2007
A. Waterbody Segmentation Fountain Creek Segment 1b was created for Severy Creek and all tributaries from the source to a point just upstream of where US Forest Service Road 330 crosses the stream. Fountain Creek Segment 3b was created for Bear Creek and all tributaries from the source to a point upstream of GPS coordinates N3847682, W 10454917 (this location is at elevation 8,200 feet above sea level at a 250° angle and 3,000 feet from the trailhead of the Mount Buckhorn Trail off High Drive). Some renumbering and/or creation of new segments in the basin was made due to information which showed that: a) the original reasons for segmentation no longer applied; b) new water quality data showed that streams should be resegmented based on changes in their water quality; and/or c) certain segments could be grouped together in one segment because they had similar quality and uses. The following changes were made:
B. Revised Aquatic Life Use Classifications The March 11, 2003 Rulemaking noted concerns relative to re-segmentation of several waters from Lower Arkansas segment 3a to segment 3b. These include Frio Canyon Creek, Borrego Canyon Creek, Munoz Canyon Creek, Williams Canyon Creek, and Castro Canyon Creek. The effect of this action was to move these drainages from a segment that was assigned a full suite of Aquatic Life Use-based numeric standards into segment 3b, which, although still assigned an Aquatic Life Use classification, is assigned Agricultural Use and Water Supply Use-based numeric criteria for inorganic and metal parameters. Noting that these tributaries to the Apishapa River exhibited ephemeral flow regimes at that time, EPA questioned whether the cumulative discharges of production water from Coal Bed Methane production wells might alter instream flows such that an aquatic community might be supported. The Division, at the permittee’s request, has inactivated the CDPS permit that had been issued for production water discharge to segment 3b. In the absence of discharge, the Commission has determined that there is not adequate potential for aquatic life use to justify the adoption of Aquatic Life Use-based numeric standards for Lower Arkansas segment 3b.
A “Water + Fish” qualifier was added for Lower Arkansas segment 1c. The qualifier was added based upon the presence of the tail-water fishery below John Martin Reservoir at the upper terminus of the segment.
C. Recreation Classifications and Standards As part of the Basic Standards hearing of 2005, recreation classifications were revised into four new classifications. The Commission reviewed the previous segment classifications (1a, 1b and 2) and determined the appropriate new classification based on classification criteria presented as part of the Basic Standards Hearing, use attainability analyses or other basis. In addition, during the 2005 Basic Standards Hearing, the transition from the use of the fecal coliform standard to E. coli standard was completed. Fecal coliform criteria were deleted from the numeric standards. Based on the information that showed existing primary contact recreation use is in place in at least a portion of the segment, the Commission converted those segments previously classified as Recreation Class1a to Recreation Class E with a 126/100 ml E. coli standard. Those segments currently classified as Recreation Class 1b were converted to Recreation Class P with a 205/100 ml E. coli standard. Based on review of existing Use Attainability Analyses showing that primary contact recreation is not attainable, the following segments were converted to Recreation Class N classification with 630/100 ml E. coli standard:
D. Addition of Water Supply Use Classification and Standards Based on review of information regarding the location of public water supplies, WS classification and standards were not added to any segments in this rulemaking hearing.
E. Agriculture Standards Numeric standards to protect the Agricultural Uses in Upper Arkansas, segment 6 were considered by parties at this rulemaking hearing. The Commission chose not to adopt these standards at this time because they are not attainable and there are no current agriculture uses present on this segment. The Commission anticipates that this issue will be revisited in 2012 if the current uses change.
F. Changes to Antidegradation Designation Outstanding Waters: The Outstanding Water (OW) designation was added to the newly defined Severy Creek (Fountain Creek segment 1b) and the new Bear Creek (Fountain Creek segment 3b) segments based upon information developed by Trout Unlimited documenting the presence of genetically isolated populations of cutthroat trout in both streams.
Decoupling Cold 2 and UP: As part of the Basic Standards hearing of 2005, the Commission eliminated the direct linkage between cold-water aquatic life class 2 and the use-protected designation. Therefore, all cold-water aquatic life class 2 segments that are use-protected were reviewed to determine if that designation is still warranted. The following segments are now reviewable: Upper Arkansas River segments 8a, 17b, 21a and 21b Decoupling Aquatic Life Warm 2 and UP. Also as part of the Basic Standards hearing of 2005, the Commission decided that the presence of a warm water class 2 classification would still be a presumptive basis for applying a use-protected designation; however, that presumption can be overcome if there is data showing that the water is of high quality. Therefore, the Commission reviewed all warm water class 2 segments to determine if the use protected designation is still warranted. The following segments are now reviewable:
G. Ambient Quality-Based Standards There are several segments in the Basins that are assigned ambient standards. Ambient standards are adopted where natural or irreversible man-induced conditions result in exceedances of table value standards. The Commission reviewed the information that is the basis for these standards as well as any new information that would indicate whether they are still appropriate, need to be modified, or should be dropped.
The Commission adopted ambient-based standards for selenium for the following segments: Middle Arkansas segment 3, Middle Arkansas, segment 4a The Commission deleted ambient-based standards for the following segments: Upper Arkansas segment 8b, Iowa Gulch: This standard, Zn(ch)=430, was previously disapproved by EPA and the Commission did not feel that the ambient standard was appropriate. An investigation of the causes and sources should be conducted through the TMDL Program. Fountain Creek segment 2a: The Commission deleted the ambient-based total recoverable iron standard for this segment because the current ambient concentrations of iron are meeting table value standards even though they are close to exceeding the table value standard. This segment had an ambient standard for iron previously, and the Commission acknowledges that an ambient standard may be appropriate in the future, based on updated monitoring information.
H. Aquatic Life Metals Standards New Table Value Standards: As part of the Basic Standards hearing of 2005, new zinc and cadmium table values were adopted. The acute and chronic zinc and cadmium equations in 32.6(3) were modified to conform to Regulation No. 31.
I. Arsenic Standards For arsenic, each use (except recreation) has different arsenic (“As” ) value, including Fish Ingestion (FI) and Water Plus Fish (W+F). In different combinations of uses, different values become the most limiting. In order to eliminate the confusion, the Commission added the operative value to the individual segments. The following matrix displays the most limiting arsenic criteria. Most Limiting Arsenic Criteria Depending on the Possible Combinations of Uses and Qualifiers If the Use These Arsenic Classifications were: Standards were Applied (dissolved unless otherwise noted)
Class 2 aquatic life (water As(ac) = 340, As(ch) = + fish standards), water 0.02 (trec)
supply Class 2 aquatic life (no As(ac) = 340, As(ch) = fish ingestion standards), 0.02 – 10 (trec)
water supply Class 1 aquatic life As(ac) = 340, As(ch) =
Class 2 aquatic life (fish As(ac) = 340, As(ch) = ingestion standards) 7.6 (trec)
Class 2 aquatic life (no As(ac) = 340, As(ch) = fish ingestion standards), 100 (trec)
agriculture Agriculture only As(ch) = 100 (trec)
Water supply only As(ch) = 0.02 – 10 (trec)
J Uranium Standards The previous basin-wide Uranium standard of 30 pCi/l was changed to 30 ug/l in order to conform with June 2005 changes to Regulation No. 31. Available water quality data indicates that several segments in the Middle and Lower Arkansas basin exceed the newly assigned standard. Although no temporary modifications for Uranium were assigned in these basins, due to the absence of dischargers who might be expected to discharge significant concentrations of Uranium, the Commission expects the Division to include any such waters in its proposed 2008 List of Impaired Waters and Monitoring and Evaluation Lists, as appropriate.
K. Temporary Modifications Language was added to subsection 32.6(2) [or 36.6(2)] to explain the terms “type i” and “type iii” temporary modifications.
All temporary modifications were re-examined to determine whether to delete the temporary modification or to extend them, either as existing, or with modifications of the numeric standards. Because of the June 2005 changes to Regulation No. 31, temporary modifications were not automatically extended if non-attainment persisted.
The following segments had temporary modifications that are being removed because current ambient conditions are meeting the applicable underlying standards: Upper Arkansas Segment 1b: Pb(ch)=6.5 and Zn(ch)=137, Expiration date of 12/31/07. Upper Arkansas Segment 3: Pb(ch)=1.8 and Zn(ch)=101, Expiration date of 12/31/07. Upper Arkansas Segment 5: Zn(ch)=78, Expiration date of 12/31/07. Upper Arkansas Segment 7: Zn(ch)=115, Expiration date of 12/31/07. Upper Arkansas Segment 22a: pH=5.6-9.0, Expiration date of 12/31/07. Fountain Creek Segment 1a: F.Coli=229/100 mL, Expiration date of 12/31/07. Fountain Creek Segment 2b: Se(ch)=23, Expiration date of 12/31/07. Fountain Creek Segment 6: Se(ch)=10, Expiration date of 12/31/07. Middle Arkansas Segment 2: E. coli=349/100 mL, Expiration date of 12/31/07. Middle Arkansas Segment 3: Se(ch)=11.7, Expiration date of 12/31/07. Middle Arkansas Segment 4a: Se(ch)=710, Expiration date of 12/31/07. Middle Arkansas Segment 14: Se(ch)=6, Expiration date of 12/31/07. Middle Arkansas Segment 18a: Zn(ch)=542, Expiration date of 12/31/07. Middle Arkansas Segment 13: F. coliform=336, Expiration date of 12/31/07. Lower Arkansas Segment 2a: Fe(ch)=2179, Expiration date of 12/31/07 Lower Arkansas Segment 3a: Fe(ch)=2500 and Se(ch)=52, Expiration date of 12/31/07 Lower Arkansas Segment 9c: Fe(ch)=4875, Expiration date of 12/31/07. The following segments have new or extended temporary modifications. As specified in 61.8(2)(c)(iii) (the Permit Rules, Regulation No. 61), where a temporary modification has been adopted, limits in permits are to be set based on the temporary modification and the provision strictly limiting the loading from the facility does not apply. These temporary modifications will be subject to review and rulemaking for the two years before their scheduled expiration in order to track progress towards the full attainment of water body standards and uses.
Upper Arkansas segment 3: Cd(ch)=0.48, expiration date = 12/31/2012. This type (iii) temporary modification is intended to allow remediation. The need for these temporary modifications will be reviewed in 2010 and 2011.
Upper Arkansas segment 8b: Cd(ch)=1.2, Pb(ch)=6, and Zn(ch)=295, expiration date = 12/31/2012. This temporary modification is intended to allow Res-ASARCO JV, Black Cloud Mine, adequate time to assess any potential changes to its discharge permit. The need for these temporary modifications will be reviewed in 2010 and 2011. Upper Arkansas segment 12a: Zn(ch)=120, expiration date = 12/31/2012. This temporary modification is intended to allow Young Life Frontier Ranch, DOW-Chalk Cliffs Fish Hatchery, Christian Mission and Mt. Princeton Hot Springs adequate time to assess any potential changes to discharge permits. The need for these temporary modifications will be reviewed in 2010 and 2011.
Fountain Creek segment 1a: Se(ch)=8.7, expiration date = 12/31/2012. This temporary modification is intended to allow City of Colorado Springs, Castle Concrete Co., Colorado Springs Utility and Manitou Springs adequate time to assess any potential changes to discharge permits. The need for this temporary modification will be reviewed in 2010 and 2011. Fountain Creek segment 2a: Cu(ac/ch)=current condition, expiration date = 12/31/2009. This temporary modification is intended to allow the Security Sanitation District adequate time to assess any potential changes to its discharge permit. The need for this temporary modification will be reviewed in 2007 and 2008.
Fountain Creek segment 3a: Pb(ch)=2.1, expiration date = 12/31/2012. This temporary modification is intended to allow Cherokee WSD adequate time to assess any potential changes to its discharge permit. The need for this temporary modification will be reviewed in 2010 and 2011.
Fountain Creek segment 6: Cu(ac/ch)=current condition, expiration date = 12/31/2009. This temporary modification is intended to allow CSU, Coperstone, City of Colorado Springs, Sun Construction and Tri-Lakes WWTF adequate time to assess any potential changes to discharge permits. The need for this temporary modification will be reviewed in 2007 and 2008. Middle Arkansas segment 4b: Se(ch)=5.6, expiration date of 12/31/2012. Middle Arkansas segment 5: Se(ch) =18.7, expiration date of 12/31/2012. Middle Arkansas segment 6: Se(ch)=39.0, expiration date of 12/31/2012. Middle Arkansas segment 9: Se(ch)=8.6 expiration date of 12/31/2012. Middle Arkansas segment 10: Se(ch)=15.0, expiration date of 12/31/2012. Middle Arkansas segment 12: Se(ch)=29.5, expiration date of 12/31/2012. Middle Arkansas segment 18a: Se(ch)=179.0, expiration date of 12/31/2012. Lower Arkansas segment 1a: Se(ch) =existing quality (type i), SO =existing quality (type i) expiration date of 12/31/2012.
Lower Arkansas segment 1b: Se(ch) =17, expiration date of 12/31/2012. Lower Arkansas segment 1c: Se(ch) =22.5, expiration date of 12/31/2012. Lower Arkansas segment 2a: Fe(Trec)=2179, expiration date of 12/31/2012. Lower Arkansas segment 4: Se(ch) =27, expiration date of 12/31/2012. Lower Arkansas segment 5a: Se(ch) =11.2, expiration date of 12/31/2012. Lower Arkansas segment 6: Se(ch) =21.3, expiration date of 12/31/2012. Lower Arkansas segment 7: Se(ch) =6.4, expiration date of 12/31/2012. Lower Arkansas segment 9a: Se(ch) =17.8, expiration date of 12/31/2012. Lower Arkansas segment 9b: Se(ch) =52.4, expiration date of 12/31/2012. Lower Arkansas segment 9c: Se(ch) =15, expiration date of 12/31/2012. Lower Arkansas segment 11: Se(ch) =17, expiration date of 12/31/2012.
L. Site-Specific Revisions Upper Arkansas Segment 20 - In the 2002 Basin hearing, the Division proposed to add the water supply classification and associated water quality standards to segment 20. CC&V presented testimony at that hearing which showed that naturally elevated levels of manganese and sulfate were of concern and suggested a resegmentation. In response, the Division suggested that a footnote be adopted stating that the manganese standard should apply at the point of intake. This was done for manganese but sulfate was inadvertently omitted. The Commission revised the existing footnote to include sulfate. Wildhorse Creek, Middle Arkansas River segment 4a – The Commission adopted a site-specific ambient-based selenium standard for this segment based upon information documenting both the natural sources of selenium in the basin and the lack of anthropogenic activity that might potentially exacerbate instream selenium loads.
M. Other changes The Commission corrected several typographical and spelling errors, and clarified segment descriptions. The reference to “Water+Fish Organics ” was corrected to “Water+Fish Standards ” to incorporate the appropriate standards from both the organics table and the metal parameter table in Regulation No. 31. The reference to “Fish Organics ” was corrected to “Fish Ingestion Standards ” to incorporate the appropriate standards from both the organics table and the metal parameter table in Regulation No. 31. The segment description for Upper Arkansas, segment 5 was changed from “except for specific listings in Segments 6 through 12” to “except for specific listings in Segments 6 through 12b” The segment description for Upper Arkansas, segment 12b was changed from “from the sources” to “from the source” .
The segment description was changed for Upper Arkansas, segment 16a to exclude the reference to Section 9 to T17S, R73W.
The segment description was changed for Upper Arkansas, segment 17b to exclude the reference to Section 1 to T17S, R72W.
The Footnote to Table one in connection to Upper Arkansas, segment 20 was corrected to include sulfate in addition to dissolved manganese.
The segment description was changed for Lower Arkansas, segment 3a to exclude Lower Arkansas segment 3c.
The segment description was changed for Lower Arkansas, segment 5a to clarify the segment description.
N. Arkansas River above Birdseye Gulch, Upper Arkansas River segment 1b (Proposal by Climax Molybdenum (“Climax” ))
The previously appl icable temporary modifications of Pb(ch) = 6.5 µg/L and Zn(ch) = 137 µg/L are deleted and an ambient based standard of Zn(ac) = 150 µg/L is adopted. A TMDL was cooperatively developed for Segment 1b by the Division and Climax in 2003 and subsequently approved by EPA. Climax took voluntary action in 2005 to remove and reclaim tailings identified in the TMDL that contributed to lead and zinc loadings in Segment 1b. The Commission found that this remedial action, together with the previous reclamation of the Climax property, resulted in an irreversible man-induced ambient water quality level for acute zinc that is higher than TVS but is adequate to protect the classified uses. Therefore, pursuant to Regulation 31.7(1)(b)(ii), the Commission adopted a site-specific acute standard for zinc based on the 95th percentile of the available data for the last three-year period of record.
O. California Gulch Superfund Site, Upper Arkansas River segments 2b, 2c, 5 and 6 (Proposal by Hazardous Materials Waste Management Division)
Historic mining activities in and around the California Gulch basin have significantly impacted water quality in segments 2b, 2c, and 6 of the Upper Arkansas River. Environmental remediation of mine wastes within the California Gulch Superfund Site has resulted in significant improvement of the water quality within these segments. Additional water quality improvements are expected as Site remediation is completed. Accordingly, the Commission is adopting revised numeric standards for cadmium and zinc for segments 2b and 2c. The revised numeric standards will serve as future remediation goals for the Site. Furthermore, the Commission has reclassified the tributaries of California Gulch from segment 5 to segment 6 to more accurately reflect the use and characteristics of those tributaries. Upper Arkansas segments 2b and 2c of the Arkansas River Basin Revised Numeric Standards for Cadmium and Zinc - The revised cadmium and zinc numeric standards for segments 2b and 2c are based on the application of the EPA approved recalculation methodology. GEI Consultants Inc./Chadwick Ecological Division completed the recalculation on behalf of Resurrection Mining Company, one of the PRPs implementing portions of the Superfund remediation. The recalculation methodology provides new numeric standards for cadmium and zinc that are protective of the aquatic communities found in segments 2b and 2c of the Arkansas River Basin. The cadmium and zinc numeric standards derived from the recalculation methodology are intended to guide additional remediation work within the Site. Because remediation work at the site is ongoing, the Commission is aware actual water quality within segments 2b and 2c will occasionally exceed the revised cadmium and zinc numeric standards over the next three to five years, especially during spring run-off conditions. For this reason, the Commission also adopted a seasonal temporary modification for the months of April and May for both segments 2b and 2c. The Commission rejected a proposal by Trout Unlimited that the temporary modification period be extended to June, since the data shows that the standards are attained during the month of June. Seasonal Type (i) Temporary Modifications - For Segment 2b, the Commission adopted 649 µg/l as the temporary zinc numeric standard and adopted 1.34 µg/l as the temporary cadmium numeric standard. For segment 2c, the Commission adopted 225 µg/l as the temporary zinc numeric standard and adopted 0.79 µg/l as the temporary cadmium numeric standard. These were calculated as seasonal temporary modifications by using 85 th percentile of all available water quality data and average hardness data collected during the months of April and May from 2001-2006. In adopting the seasonal temporary modifications, the Commission acknowledged the uncertainty regarding long-term water quality conditions following completion of remediation activities at the Site. This uncertainty arises because water quality improvements resulting from source remediation projects will not be known for a period of time following the completion of the activities because the source control will not always immediately impact water quality within segments 2b and 2c.
Upper Arkansas segments 2b and 2c of the Arkansas River Basin Revised Antidegradation Baseline - Based on continued remediation activities at the Site, the Commission determined that the default baseline for antidegradation established in the September 30, 2000 Basic Standards no longer applies to segments 2b and 2c. Accordingly, the Commission adopted a revised anti-degradation baseline for segments 2b and 2c, including a note in the designation column in the Stream Classifications and Water Quality Standards tables to indicate that the September 30, 2000 default baseline date does not apply to these specific segments. In accordance with the Basic Standards (5 CCR 31.8(3)(c)(ii)(B)), the Commission found that the appropriate baseline date and baseline water quality should be determined at the time that any new activity triggers an anti-degradation review. Thus, the Commission adopted a revised anti-degradation baseline for segments 2b and 2c whereby the anti-degradation review and collection of water quality data shall commence upon the same date any new activity occurs in either segment 2b or 2c.
Upper Arkansas segments 5 and 6 of the Arkansas River Basin - The Commission determined that California Gulch tributaries, previously classified within segment 5 as Aquatic Life Cold 1, Recreation 1a, Water Supply, and Agriculture, were inappropriately classified. This determination is based on the use, physical characteristics, and water quality characteristics of the California Gulch tributaries, which include Malta, Airport, Pawnee, Georgia, Oregon, Nugget, White, Stray Horse and Little Stray Horse Gulch. Specifically, the Commission’s review of evidence presented during the 2007 rulemaking hearing, and re- evaluation of the 1990 Use Attainability Analysis (“UAA” ) of California Gulch performed by the Colorado Division of Wildlife (“CDOW” ), indicated that the California Gulch tributaries lacked qualities to appropriately identify them as Aquatic Life Cold 1, Recreation 1a, and Water Supply. In an earlier rulemaking, the Commission relied on CDOW’s 1990 UAA to establish that segment 6 should not contain numeric water quality standards. While current evidence indicates that California Gulch water quality has improved since the 1990 UAA, the conditions outlined in the 1990 UAA continue to limit potential aquatic communities in California Gulch and its tributaries. Therefore, the Commission determined it is inappropriate to maintain numeric water quality standards for those tributaries, and concluded that those California Gulch tributaries located in segment 5 should be reclassified as part of segment 6 as Recreation 2, Agriculture.
P. Mainstem of Cripple Creek (Proposal by Cripple Creek and Victor Gold Mining Corporation) CC&V originally proposed that a qualifier be added to Segment 21 noting that fish were present only in the lower 1.5 miles of Cripple Creek, based on study results from long-term monitoring of the aquatic community in Cripple Creek showing that fish existed only in the lower 1.5 miles of Cripple Creek because of physical barriers, flow constraints, and habitat conditions. The Division's alternate proposal was to resegment Cripple Creek into Segments 21a and 21b. Regulation 31.6(4)(c) provides that segments will generally be delineated according to points where the use, physical characteristics or water quality characteristics change significantly enough to require a change in use classifications or water quality standards. The Commission accordingly resegmented Segment 21. The water quality standards of Segment 21a are based on protection of aquatic life without fish and the water quality standards of Segment 21b are based on full protection of aquatic life, including trout. In this rulemaking the Commission considered two separate proposals to add a water supply classification to segments immediately upstream of segments with existing water supplies. (Upper Arkansas segment 21 and Middle Arkansas segment 4e). The Commission has determined that it is not appropriate to add a water supply classification to either of these segments at this time. The evidence submitted does not demonstrate an immediate threat to either water supply that is not adequately addressed by existing water supply classifications for the segments from which the water supplies are withdrawn. However, with the evolution of source water planning and protection efforts under the State's drinking water program, the Commission believes that the relationship between surface water use classifications and source water protection efforts should be explored further. In general, the Commission believes that the water quality classification and standards system should be consistent with and supportive of source water protection efforts. The Commission requests that the Division work with interested stakeholders to develop a proposed approach to this issue for consideration in future rulemaking actions. Depending upon the results of such discussions, it may be appropriate to revisit either or both of the water supply classification proposals advanced in this rulemaking during a future review of this basin. The Division proposed that the use-protected designation be removed from Segment 21, since the presumption that such a designation is appropriate for aquatic life class 2 cold water streams has been eliminated. CC&V argued that the use-protected designation should be retained, based on an argument that Segment 21 is an effluent dominated stream. The Commission has determined that the data and analysis submitted by CC&V is not adequate to demonstrate that Segments 21a and 21b meet the effluent dominated definition, because using average conditions in a comparison does not appropriately characterize what occurs in a year that is wetter or drier than average. It is inappropriate to extrapolate from a comparison of the average condition to that which occurs eight out of ten years.
Q. Golf Course Wash (Proposal by Pueblo West Metropolitan District) Pueblo West Metropolitan District proposed resegmentation of Golf Course Wash, a tributary to Pueblo Reservoir, from Middle Arkansas Segment 4d to a new Segment 4e. They proposed this new segment be classified as aquatic life warm class 2, recreation class E and agriculture with a use-protected designation. Numeric standards would be applied only for recreation and agriculture uses with the addition of ammonia. A temporary modification of the ammonia standards of NH (ac/ch)=TVS old was also proposed. The Commission declined to adopt this temporary modification because the evidence submitted did not demonstrate a need for the temporary modification. Rather, the evidence demonstrated that Pueblo West may be able to comply with the new ammonia standard. Should further investigation demonstrate that additional time will be required to comply with the ammonia standard, the Commission assumes that a discharge permit compliance schedule may be available. If it should be determined that a compliance schedule is not available or not adequate for Pueblo West to comply with the ammonia standard, a temporary modification can be reconsidered at a later date. Pueblo Board of Water Works provided an alternative proposal to add a water supply classification or at least a full suite of numeric standards to protect aquatic life, because the downstream segment (Pueblo Reservoir) serves as the City’s water supply. The Commission has determined that the adoption of a water supply classification or additional standards to protect this use is not appropriate at this time, as explained above in section P of this statement of basis and purpose, R. Monument Creek (Copper) (Proposal by Tri-Lakes Wastewater Treatment Facility) Tri-Lakes Wastewater Treatment Facility proposed a site-specific copper water effects ratio for segment 6 of Monument Creek using a combination of the streamlined water effects ratio (WER) and the Biotic Ligand Model (BLM). In response to EPA’s February 2007 Copper Criteria, Tri-Lakes revised their proposal to a temporary modification based on uncertainty. The Commission adopted Tri-Lakes revised proposal.
This temporary modification recognizes the uncertainty created by the evolving guidance regarding use of the WER, BLM, or other appropriate copper standard to protect the aquatic life use, as well as uncertainty about whether protective levels can feasibly be attained in the effluent of the Tri-Lakes WWTF. An additional source of uncertainty is whether or not a translator study will provide adequate relief for the WWTF.
The temporary modification has been set to expire on December 31, 2009. During the term of the temporary modification Tri-Lakes will investigate the efficacy of a translator from dissolved criterion to a potentially dissolved (or total recoverable) permit limit. In addition, the Commission anticipates that there will be an expanded dialogue between EPA, the Division and interested parties regarding the appropriate methods for setting site-specific copper stream standards. With a 2009 expiration date, Tri-Lakes’ progress will be reported to the Commission at the December 2007 and December 2008 annual Temporary Modification Review hearing, and the need for the temporary modification will be reviewed at that time. If a translator is inadequate, the Commission recognizes that more time may be needed to develop a site-specific standards proposal. The temporary modification is set at “current condition.” It is the intention of the Commission that when implementing this temporary modification in a CDPS permit, and interpreting the term current condition, the Division will assess the current effluent quality, recognizing that it changes over time due to variability in treatment plant removal efficiency and influent loading from industrial, commercial, and residential sources. One necessary element of an approach to maintain the current condition would be a requirement that the total loading from commercial and industrial contributors be maintained at that level as of the date of adoption of the temporary modification and that neither the concentration nor the frequency of high concentration shall increase over historic levels and frequency.
S. Proposal by Colorado Trout Unlimited - Outstanding Waters Designation for Severy and Bear Creeks Based on evidence that shows that water quality meets the requirements of 31.8(2)a, the Outstanding Water (OW) designation was added to the new Fountain Creek Segment 1b: Severy Creek, and all tributaries, from the source to a point immediately upstream to where US Forest Service Road 330 crosses the stream and the new Fountain Creek Segment 3b: Bear Creek, and all tributaries, from the source to a point upstream of GPS coordinates N3847682, W10454917 (this location is at elevation 8,200 feet above sea level at a 250 ° angle and 3,000 feet from the trailhead of the Mount Buckhorn Trail off High Drive). Two new segments were created for these two waters. The Commission understands that there are existing land uses in place in these watersheds. The evidence demonstrates that these existing land uses are compatible with the OW designation since the current high level of water quality has been attained with these uses in place. It is the Commission’s intent that this OW designation should not be used to establish additional permit requirements for existing uses within this area.
T. Fountain Creek (Copper) (Proposal by Security Sanitation District) Security Sanitation District proposed a site-specific copper water effects ratio for segments 2a of Fountain Creek using a combination of the streamlined water effects ratio (WER) and the Biotic Ligand Model (BLM). In response to EPA’s February 2007 Copper Criteria, Security revised their proposal to a temporary modification based on uncertainty. The Commission adopted Security’s revised proposal. Similar to the situation on Monument Creek segment 6 (discussed above) this temporary modification recognizes the uncertainty created by the evolving guidance regarding use of the WER, BLM, or other appropriate copper standard to protect the aquatic life use, as well as uncertainty about whether protective levels can feasibly be attained in the effluent of the Security WWTF. An additional source of uncertainty is whether or not a translator study will provide adequate relief for the WWTF. The temporary modification has been set to expire on December 31, 2009. During the term of the temporary modification Security will investigate the efficacy of a translator from dissolved criterion to a potentially dissolved (or total recoverable) permit limit. In addition, the Commission anticipates that there will be an expanded dialogue between EPA, the Division and interested parties regarding the appropriate methods for setting site-specific copper stream standards. With a 2009 expiration date, Security’s progress will be reported to the Commission at the December 2007 and December 2008 annual Temporary Modification Review hearings, and the need for the temporary modification will be reviewed at that time. If a translator is inadequate, the Commission recognizes that more time may be needed to develop a site-specific standards proposal. The temporary modification is set at “current condition.” It is the intention of the Commission that this term be interpreted as discussed in section R above.
U. Selenium and Sulfate near Pueblo (Proposal by the City of Pueblo) The Commission adopted site-specific ambient- and attainability-based underlying standards for selenium on several segments in the Middle and Lower Arkansas, and Fountain Creek sub-basins. These included Fountain Creek segment 2b, Middle Arkansas segments 3 and 4a, and Lower Arkansas segment 1a. Ambient-based standards were adopted for Middle Arkansas segments 3 and 4a based upon showings by the City of Pueblo and the Division, respectively, that selenium loading to both segments results from natural sources and is not exacerbated by land use or other reversible, anthropogenic factor. Evidence developed by the City of Pueblo indicates that some degree of selenium and sulfate load reduction is attainable for Fountain Creek segment 2b and Lower Arkansas segment 1a. Reductions of one and six percent respectively are feasible given the current extent of irrigated agriculture within these two sub-basins. The Commission has therefore adopted attainability-based underlying selenium and sulfate standards for these segments, while retaining temporary modifications set at existing levels. The temporary modifications for selenium and sulfate in Lower Arkansas segment 1a are identified as type i temporary modifications. The expectation is that the Division and stakeholders will identify appropriate Best Management Practices as necessary to achieve the necessary load reductions within a twenty-year period.
V. Lower Arkansas Segment 1a Selenium (Proposal by the City of LaJunta) The City of La Junta proposed a type iii temporary modification for selenium for Lower Arkansas segment 1b of 27.1 ug/L chronic and 36 ug/L acute, with an expiration date of December 31, 2020. Based on discussion with the Division, La Junta revised its proposal to be “Se = current condition, expiration date 12/31/2009” . The Commission has adopted La Junta’s revised proposal. This temporary modification recognizes the uncertainty regarding the relative magnitude of natural sources, irreversible man-induced sources and reversible sources of selenium. There is also uncertainty regarding what levels are appropriate to protect the aquatic life use. In addition, there is uncertainty about whether protective levels can feasibly be attained in the effluent of La Junta’s WWTF. The temporary modification has been set to expire on December 31, 2009. During the term of the temporary modification La Junta will investigate the efficacy of modifying the way RO brine is blended with their traditional wastewater.
With a 2009 expiration date, La Junta’s progress will be reported to the Commission at the December 2007 and December 2008 annual Temporary Modification Review hearings, and the need for the temporary modification will be reviewed at that time. During this same time, the Division will continue to support efforts to quantify selenium loading, particularly selenium loads from un-irrigated upland areas, and to begin to implement selenium reductions, which will take longer than two years. The temporary modification is set at “current condition.” It is the intention of the Commission that when implementing this temporary modification in a CDPS permit, and interpreting the term current condition, the Division will assess the current effluent quality, recognizing that it changes over time due to variability in treatment plant removal efficiency and influent loading from industrial, commercial, and residential sources. One necessary element of an approach to maintain the current condition would be a requirement that the total loading from commercial and industrial contributors be maintained at that level as of the date of adoption of the temporary modification and that neither the concentration nor the frequency of high concentration shall increase over historic levels and frequency.
W. Proposal by the State of Kansas The State of Kansas presented information that salinity and selenium concentrations increase between John Martin Reservoir and the state line (Lower Arkansas segment 1c), and that the concentrations of these constituents has increased over the last decade. Kansas participated in this rulemaking in order to expedite the identification of appropriate water quality endpoints for Lower Arkansas segment 1c, thereby facilitating development of TMDLs addressing these parameters. The Commission decided that, while adequate information is available to characterize irreversible selenium loading on several segments within the Arkansas basin, such is not yet the case in the lowermost portion of the basin. The Commission does, however, acknowledge the efforts undertaken by Kansas to address these pollutants in TMDLs promulgated earlier (sulfate), and planned for later this year (selenium) for the Arkansas River as it enters Kansas. The Commission expects the Division to work closely with the State of Kansas and stakeholders in addressing these issues upstream of the state line. The Division will work on UAAs to support attainable underlying standards, TMDLs where appropriate underlying standards have been adopted and implementation of remedial actions (BMPs) throughout the basin to reduce the loading of selenium.
Kansas asked the Commission to establish a Salinity Task Force that would lay the ground work for evaluating research results, selecting appropriate BMP’s and formulating a long-term strategy of salt load reduction to the river. At this time, the Commission cannot commit to such an expenditure of resources. However, the state is supporting a watershed restoration planning effort sponsored by Southeast Colorado Resource Conservation and Development with Clean Water Act Section 319 funding. Later this fall Colorado will be in a better position to determine whether resources are available that could be allocated towards this issue. The Division will be completing a statewide prioritization of watershed restoration of impaired waters (as required by EPA) and will report the information to the Commission. This information may be used by the Commission to recommend revisions to the proposed priority watersheds.
1. Hazardous Materials and Waste Management Division 2. Hazardous Materials and Waste Management Division 3. State of Kansas 4. City of Pueblo 5. Tri-Lakes Wastewater Treatment Facility 6. Cripple Creek and Victor Gold Mining Company 7. Climax Molybdenum Company 8. Security Sanitation District 9. Pueblo West Metro District 10. The Paint Brush Hill Metropolitan District 11. Colorado Trout Unlimited 12. Homestake Mining Company of California 13. City of Cripple Creek Water/Wastewater Department 14. Colorado Wild 15. The National Park Service at Great Sand Dunes National Park and Preserve 16. Park Center Water District 17. Xcel Energy 18. Alamosa Riverkeeper 19. The City of La Junta 20. Corrections Corporation of America 21. Rocky Mountain Steel Mills.
22. Colorado Division of Wildlife 23. The City of Colorado Springs 24. The Board of Water Works of Pueblo, Colorado 25. U.S. Environmental Protection Agency 26. Pikes Peak Area Council of Governments 32.41 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; JULY 15, 2008 RULEMAKING; ADOPTED JULY 15, 2008; EFFECTIVE AUGUST 30, 2008 The provisions of C.R.S. 25-8-202(1)(a), (b) and (2); 25-8-203; 25-8-204; and 25-8-402; provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted in compliance with 24-4-103(4) C.R.S. the following statement of basis and purpose. BASIS AND PURPOSE The Commission adopted changes to the segment description of Lower Arkansas segment 5a that re- instated the wording deleted in the June 2007 rulemaking hearing. The intent of the 2007 changes was merely to simplify the segment description. However, subsequent to the hearing it was found that unintended significant changes had resulted from the revised segment description. This change in 2008 corrects that error.
_____________________________________________________ Editor’s Notes History Editor’s Notes History 32.5; 32.10; 32.11; 32.24; 32.40; 32.41 eff. 7/1/2007. Entire rule eff. 09/01/2007. 32.1 - 32.6, 32.40 eff. 12/31/2007. Table 32.6-3 Pg14, New Section 32.41 Eff. 08/30/2008.