5 CCR 1002-93
DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT Water Quality Control Commission REGULATION #93 - SECTION 303(d) LIST WATER-QUALITY-LIMITED SEGMENTS REQUIRING TMDLS 5 CCR 1002-93 [Editor’s Notes follow the text of the rules at the end of this CCR Document.]
93.1 Authority
These regulations are promulgated pursuant to section 25-8-101 et seq C.R.S. as amended, and in particular, 25-8-202 (1) (a), (b), (i), (2) and (6); 25-8-203 and 25-8-204.
93.2 Purpose
This regulation establishes Colorado’s List of Water-Quality-Limited Segments Requiring Total Maximum Daily Loads (“TMDLs” ). This list fulfills section 303(d) of the federal Clean Water Act which requires that states submit to the U.S. Environmental Protection Agency a list of those waters for which technology- based effluent limitations and other required controls are not stringent enough to implement water quality standards.
93.3 Water-Quality-Limited Segments Requiring TMDLS
Listings marked with an asterisk (*) are carryover from the 1998 303(d) List. Consequently they are all high priority.
COARFO01a Fountain Creek and all E. coli , Se tributaries above Monument Creek COARFO02a Fountain Creek, all E. coli Monument Creek to Hwy COARFO02b Fountain Creek from all Se Hwy 47 to the Arkansas COARFO04 All tribs to Fountain all E.coli Creek, which are not on National Forest or Air Force Academy Land COARFO06 Monument Creek from Below Mesa Road Se National Forest to Fountain Creek COARFO07a Pikeview Reservoir, Willow Springs Ponds #1 Aquatic Life Use (PCE Willow Springs Ponds #1 & #2 FCA)
Creek and Gageby Creek… COARLA09a Mainstem of Adobe Adobe Creek E. coli Creek and Gageby Creek… COARLA09b Apache Creek, all Se Breckenridge Creek, Little Horse Creek, Bob Creek, Wildhorse Creek, Wolf Creek, Big Sandy Creek COARLA09c Rule Creek, Muddy Chicosa Creek Fe(Trec), Se Creek, Caddoa Creek, Clay Creek, Cat Creek… COARLA10 Two Buttes Res., Two Adobe Creek Res., Nee Se Buttes Pond, Hasty Lake, Gronda Res Holbrook Res., Burchfield Lake, Nee- Skah (Queens) Res., Adobe Creek Res., Neeso Pah Res., Nee Nosha Res., Nee Gronda Res.
COARLA11 John Martin Reservoir all Se COARLA12 Lake Henry, Lake all Se Meredith COARMA04a Wildhorse Creek all E. coli COARMA06 St. Charles River and all Se tributaries, CF&I diversion to Arkansas COARMA10 Sixmile Creek all Fe(Trec), Se COARMA12 Huerfano River, from all Se Muddy Creek to the Arkansas River COARMA14 Cucharas River, from all Se Walsenburg PWS diversion to the outlet of Cucharas Reservoir COARMA16 Huajatolla Reservoir, Horseshoe Lake Aquatic Life Use (Hg Diagre Reservoir, FCA)
COARMA18a Boggs Creek all Se, Zn, U COARUA02a Arkansas River, Birdseye all Zn, NO5 Gulch to California Gulch COARUA02b Arkansas River, all Cd*, Zn* California Gulch to Lake Fork COARUA02c Arkansas River, Lake all Zn*,Cd Fork to Lake Creek COARUA03 Arkansas River, Lake all Zn, Cd Creek to Pueblo Reservoir COARUA05 Arkansas River tributaries Halfmoon Creek Pb, Cd from source to Brown's Creek COARUA07 Evans Gulch from source all Zn to Arkansas River CAORUA08b Iowa Gulch from all Cd, Pb, Zn ASARCO water supply intake to Paddock #1 Ditch (Iowa Ditch)
COARUA10 Mainstem of Lake Creek all pH, D.O., Cu and all tributaries, lakes and reservoirs from source to Arkansas River (including Twin Lakes Reservoir)
COARUA11 South Fork Lake Creek, all pH, Al, Cu*, Zn, Cd source to Lake Creek COARUA12a Chalk Ck. below Mary Murphy Zn, Pb Mine COARUA15 Grape Creek including De Weese Reservoir D.O.
COGULG02 Gunnison River, all Se* Uncompaghre River to Colorado River COGULG04a Tributaries to Gunnison all Se River, Crystal Reservoir to Colorado River COGULG04b Tributaries to Gunnison Kannah Creek below Se River, Kannah Creek USGS station 09152000 COGULG04c Red Rock Creek within all Se Black Canyon of the Gunnison National Park COGULG09 Fruitgrowers Reservoir all D.O.
COGUNF03 North Fork of the all Se Gunnison from Black Bridge above Paonia to the confluence within the Gunnison COGUNF05 Hubbard, Terror, Leroux Creek, Jay Creek, Se* Minnesota and Leroux Creeks from USFS boundary to N. Fork.
Mountain Creek to Montrose COGUUN04b Uncompaghre River, La all Se* Salle Road to Confluence Park COGUUN04c Uncompaghre River, all Se* Confluence Park to Gunnison River COGUUN06a Red Mountain Creek, all Zn(sculpin)
source to East Fork Red Mountain Creek COGUUN12 Tributaries to all Se Uncompahgre River, South Canal to Gunnison COGUUN14 Sweitzer Lake all Se*, D.O.
COGULD01 Dolores River from all Fe(Trec)
Gunnison River to state line COLCLC04a Tributaries to Colorado all Se River, Roaring Fork to Parachute Creek except for specific segments COLCLC10 Rifle Creek, including all Se tributaries from County Road 251 to Colorado COLCLC13a Tributaries to Colorado Salt Creek sediment River blw Parachute Creek, except named segments COLCLC13b Tributaries to Colorado all Se River from Government Highline Canal Diversion to Salt Creek COLCLC13b Tributaries to Colorado Adobe Creek E.coli, Fe(Trec) River from Government Highline Canal Diversion to Salt Creek COLCLC13c Walker Wildlife Area all Se Ponds COLCLC14b Roan Creek & tribs, Clear Dry Fork Se Creek to the Colorado COLCLC19 Lakes and reservoirs West Pond Orchard Mesa Se tributary to the Colorado Wildlife Area River, Parachute Creek to the border COLCLY02 Yampa River, Lay Creek all Fe(Trec)
to Green River COLCLY05 Fortification Creek from all Se North and South Fork to the Yampa River COLCLY16 Little Snake River from all Fe(Trec)
Power Wash to the Yampa COLCWH09b Flag Creek and Sulphur all Se Creek COLCWH13b Mainstem of Yellow Corral Creek, Duck Creek Se Creek, including all tributaries from the source to the confluence with the White River COLCWH22 Tributaries to White West Evacuation Wash, sediment River, Douglas Creek to Douglas Creek Colorado/Utah border CORG Rio Grande River Basin . .
CORGAL02 Alamosa River, from Tribs to lower Iron Ck pH, Cu, Zn, Fe(Trec) source to confl with Alum Creek CORGAL03b Alamosa River, from Above Jasper Creek Cd Wightman Fork to Fern Creek CORGAL03d Alamosa River, from all Al Ranger Creek to Terrace Res.
CORGAL08 Terrace Reservoir all Fe(Trec)
CORGAL11 La Jara Creek including La Jara Reservoir D.O. tributaries, wetlands, lakes and reservoirs from source to Hot Creek CORGAL13 Hot Creek from source to all Fe(Trec)
CORGCB09a Kerber Creek above all Cd* Brewery Creek and tributaries, except those in segment 8 CORGCB09b Kerber Creek, Brewery all Cu* Creek to San Luis Creek CORGRG04 Rio Grande River, Cd Willow Creek to Cd*, Zn*, Cu Willow Creek to Alamosa Wagon Wheel Gap, Zn County line Willow Creek to Del Norte, Cu Del Norte to county line CORGRG07 West Willow Creek, East Nelson Creek, West pH Willow Creek, Willow Willow Creek below Creek and tributaries Nelson Creek to East Willow Creek CORGRG09 South Fork of Rio Beaver Creek Reservoir D.O.
COSJDO04b McPhee Reservoir and McPhee Reservoir Aquatic Life Use(Hg* Summit Reservoir FCA)
COSJDO09 Silver Creek from Rico all Zn, Cd DW diversion to Dolores COSJLP03a All Tributaries to the La Cherry Creek Fe(Trec) Plata River from Hay Gulch to the Southern Ute Indian reservation boundary COSJLP04a Mancos River and E. Mancos River Cu tributaries above HWY COSJLP04a Mancos River and all Zn tributaries above HWY COSJLP11 Narraguinnep, Puett, and Narraguinnep Reservoir, Aquatic Life Use(Hg* Totten Reservoir Totten Reservoir FCA)
COSJPN03 Vallecito Reservoir Vallecito Reservoir Aquatic Life Use (Hg FCA)
COSP South Platte River . .
COSPBT12 Lake Loveland, Boyd Lake Aquatic Life Use (Hg Horseshoe Lake, Boyd FCA)
COSPLS02b Tributaries to S Platte Beaver Creek Se, E. coli River, Beaver Creek, Bijou Creek and Kiowa Creek COSPMS03a Tributaries to S. Platte Horse Creek Reservoir pH River, Big Dry Creek to Weld/Morgan county line COSPMS04 Barr Lake and Milton all pH Reservoir COSPSV02 St. Vrain Creek, RMNP to all Cu Hygiene Road COSPSV04a Left Hand Creek, source pH, Cu, Zn (Hwy 72 to pH, Cu, Zn to Hwy 36 James Ck); Cu blw James Ck COSPSV04b James Creek, Little James Little James Creek Cu, Pb Creek COSPSV06 Tributaries to the St Vrain Dry Creek E. coli COSPSV06 Tributaries to the St Vrain all Se COSPUS02a Tributaries to S. Platte R, Twin Creek sediment source of S. & M. Forks to Tarryall Creek COSPUS03 Tributaries to S.Platte Trout Creek and sediment* River, Tarryall Creek to tributaries on USFS N.Fk.S.Platte R property COSPUS04 N. Fk. S. Platte River & Hall Valley area to Cu* Tributaries, source to Geneva Ck S.Platte R COSPUS05b Geneva Creek, Scott all Zn* Gomer Creek to N. Fork
Spring Creek COUCUC05 Lakes and Reservoirs Wolford Mountain D.O.
tributary to the Colorado Reservoir River from RMNP/ANRA to the Roaring Fork not on National Forest COUCUC07a All tribs to the Colorado Alkali Slough Fe (Trec), Se River, including wetlands from a point abv the confluence with the Blue River to blw confluence with the Roaring Fork, which are not on National Forest Lands except specific listings in segment 7b.
COUCYA08 Elk River source to Elk River below Morin E.coli Yampa River Ditch COUCYA13d Dry Creek Below Seneca sample Se location 8 (WSD5)
COUCYA13e Sage Creek, Grassy Creek Sage Creek below Routt Se and tribs County Road 51D COUCYA13e Sage Creek, Grassy Creek Grassy Creek below Se and tribs Routt County Road 27A COUCYA20 Tributaries to the Yampa First Creek below Second E. coli River above Elkhead Creek, Elkhead Creek Creek within National below First Creek Forest
93.4 - 93.9 Reserved
93.10 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; MARCH, 2004
A. Introduction This regulation establishes Colorado’s List of Water-Quality-Limited Segments Requiring Total Maximum Daily Loads (“TMDLs” ). This list was prepared to fulfill section 303(d) of the federal Clean Water Act (“Act” ) which requires that states submit to the U.S. Environmental Protection Agency (“EPA” ) a list of those waters for which technology-based effluent limitations and other required controls are not stringent enough to implement water quality standards.
Once listed, the State is required to prioritize these water bodies or segments (rivers, streams, lakes reservoirs) based on the severity of pollution and other factors. It will then determine the causes of the water quality problem and allocate the responsibility for controlling the pollution. This analysis is called the TMDL Process, and results in the determination of: 1) the amount of a specific pollutant that a segment can receive without exceeding a water quality standard (the TMDL), and 2) the apportionment to the different contributing sources of the pollutant loading (the allocation). The TMDL must include a margin of safety, waste load allocation (for point sources) and a load allocation (for non-point sources and natural background). The TMDL must include upstream loads in the assessment and apportionment process.
B. List Development 1. Listing Methodology The “Section 303(d) Listing Methodology - 2004 Listing Cycle” contains a description of the listing process, the criteria for listing, and the criteria for determination of TMDL priority. The Listing Methodology was developed through a public process and finalized as a policy at a Water Quality Control Commission administrative action hearing on September 9, 2003. This Listing Methodology sets forth the criteria that generally were used to make decisions regarding which waters to include on the 2004 Section 303(d) List and the 2004 M&E List. However, this methodology was not adopted by the Commission as a rule. The Commission therefore has the flexibility to take into account other appropriate factors in making site-specific listing decisions.
2. Information Considered The Commission has considered all existing and readily available information in developing the 2004 Section 303(d) List. In determining whether data and information are existing and readily available, it has taken into account such data and information as the Division has utilized in the preparation of those identification processes, calculations and models referenced in 40 CFR §130.7(a)(5)(i), (ii) and (iv) and that credible data and information presented in a readily usable format and submitted in reports provided to the Division as referenced in 40 CFR §130.7(a)(5)(iii). In addition, the Commission accepted credible data and information that was submitted in accordance with the listing process schedule, whether submitted by EPA or any other interested party. The Division also continues to independently collect and analyze new data on a rotating basin basis as part of its triennial review efforts and will utilize such data and information in making future listing determinations. Existing data which was not brought forward through one of the above mechanisms or otherwise presented to the Commission in accordance with the schedule was not treated as "readily available" for purposes of making the 2004 listing decisions. Such information will be considered in the next listing cycle.
C. Prioritization The objective of prioritization is to identify those waterbody segments where the Division and the public should concentrate their resources. Priorities of High, Medium and Low were established according to section IV. of the 2004 Section 303(d) Listing Methodology. Segments/parameters where the Commission determined that an appropriate plan is in place to resolve the uncertainty as specified in section 93.4 have been denoted as “L*” . A Low priority may also be assigned to other segments as per section IV.
D. Discussion of Issues Raised in the Hearing During the course of the hearing, the status of approximately 30 segments was debated. The basis for the Commission’s decisions regarding the major issues for these segments is recorded below.
1. Selenium: Several parties questioned whether selenium, where the source is underlying native shale, should be considered a pollutant. The Commission found that selenium, like many other naturally occurring metals in Colorado is a pollutant and is classified as such on EPA’s list of priority toxic pollutants (62 FR 42160). If the source of impairment is natural, that is grounds for consideration of an ambient quality-based, site-specific standard as described in Regulation No. 31 at 31.7 1(b)(ii). However, the listing decisions must be made based upon a comparison of the current adopted standard and the ambient condition for the segment. Although parties to the rulemaking submitted testimony questioning the decision to list several specific segments for selenium, such as Lower Colorado River segment 3 and Lower Arkansas River segment 1a, the evidence provided was directed largely at questioning the appropriateness of the current selenium standards. The Commission has determined, based on the evidence submitted, that these segments are not in attainment of the current selenium standards.
2. Segments where there is no new data, but following the 2004 Listing Methodology resulted in a different conclusion than in 2002: The following segments had no new data included in the assessments since the 2002 listing cycle. However, clarification and changes in the 2004 Listing Methodology resulted in the segments moving from the Monitoring and Evaluation List to the 303(d) List. The modifications that resulted in the most changes had to do with more clearly specifying that segments with small datasets where the ambient condition exceeds the standard by more than 50 percent should be listed. The following segments were affected: Gunnison River Basin: Lower Gunnison segment . Uncompahgre segment 2 Lower Colorado River White River segment 9b Basin:
3. Segments with multiple tributaries : Issues were raised regarding what is the appropriate way to handle segments with multiple tributaries where there is evidence of impairment. The Commission found that since segments are generally treated as having consistent uses and characteristics, their impairment should be handled in a similar fashion. Unless either water quality data or other evidence has been presented that shows that the impairment is not present in the entire segment, the entire segment has been listed as impaired. “Other evidence” may include changes in geology within a segment or the confluence with a stream known to be impaired. Nevertheless, it is anticipated that before any TMDL is developed and implemented in “all tributary” segments, work will be performed to determine the causes and locations of the impairment, such that efforts and controls are not inappropriately directed towards individual tributaries that are not truly of concern, and the Section 303(d) List can be modified accordingly. Where other evidence shows that some portions are in exceedance and other portions are not, only the impaired portion needs to be listed. The following segments were listed based on this rationale:
E. Segment- Specific Issues 1. San Juan Basin, Dolores River below McPhee Reservoir: Despite a recent decline in the fish population in this reach, the Commission found that there was not adequate readily available evidence to conclude that there exists an impairment of the aquatic life use due to other than extraordinary events associated with the long-term drought that has existed in southwest Colorado for several years. In view of evolving operations of McPhee Reservoir and varying (and generally declining) hydrologic conditions, the Commission is not able at this time to identify an “expected condition” upon which to base a decision of impairment. Further, even if an impairment caused by other than the extraordinary events associated with the drought were found to exist, the Commission could not conclude based on this record that the decline was due to a “pollutant” as compared to “pollution.” Nevertheless, the Commission encourages cooperation by all interested parties in the implementation of habitat improvement measures that may serve to enhance the quality of the fishery in the reach. The Commission is prepared to revisit the concept of “expected condition” as it applies to this reach should that be warranted by changes in habitat condition. Certainly the achievement of goals set under the 1996 Operating Agreement for McPhee Reservoir may influence the nature of the expected condition. Finally, any evidence of impairment due to pollutants can be brought forth at the next listing hearing.
2. South Platte Basin, Clear Creek, segments 14b and 15: Available data, with specific reference to biological information on fish species collected over time and visual observations of the physical condition of the stream bed, provide an indication of “use-impairment” for Clear Creek Segments 14b and 15 relative to aquatic life. Though organic sediment appears to be a significant contributor to the impairment, the exact interaction of potentially numerous causative factors need to be further explored. No single source or cause of the impairment has been identified to date. Coors Brewing Company has voluntarily come forward with a study plan for segments 14a, 14b and 15 as part of the “pilot study” approach outlined in the section 309 study report recently submitted to the State Legislature. This pilot study would assist in defining the expected condition for these segments in view of existing hydrological/habitat conditions and in fashioning the best approach to remedying the impairment. Should Coors decide to proceed with the pilot study, the Division will identify segments 14b and 15 as “low priority” and refrain from any further TMDL implementation measures until such time as the study results are known and an appropriate approach to rectifying the identified problems is crafted in cooperation with basin stakeholders.
3. Upper Colorado Basin, Blue River segments 6 and 8 (Camp Cr, Jones Gulch, Keystone Cr, and Mozart Creek): The four identified tributaries in these two segments were proposed by the Division to be listed as impaired relative to measured pH levels. The evidence submitted raised questions regarding the representativeness of the data showing a possible standards exceedance, particularly in the absence of data regarding seasonality of pH levels for multiple years. Therefore, the Commission determined that it is more appropriate to include these specific tributaries on the Monitoring and Evaluation List at this time. Keystone Resorts has stated that it will complete a Use Attainability Analysis for Camp Creek and Jones Gulch, and that it is willing to include Keystone Creek and Mozart Creek in this analysis. The Commission believes that it is appropriate to revisit the attainment status of these segments following completion of the UAA. Depending on the results of this analysis, the adoption of site-specific seasonal pH standards is one option that can be considered. Indeed, the Commission notes that the evidence submitted to it showed that nearby snowmaking actually mitigates pH levels in the snow.
4. Uncompahgre River, segment 6b (Red Mountain Creek) : The Commission does not believe that an impairment of the aquatic life use of segment 6b relative to a realistic expected condition for this segment has been shown. The Commission found that the aquatic community in segment 6a is not the appropriate expected condition for this segment. The Commission endorses the Division’s proposal not to list at this time, while moving forward to investigate segment 6b and make a recommendation to the Commission regarding the attainable aquatic life use and appropriate numeric standards in the context of the next basin-wide standards and classification rulemaking proceedings. However, it is uncertain at this time whether any future remediation activities in this area will improve the aquatic life use of this segment. In the absence of documentation that the attainable expected condition for this segment is an aquatic life use that is better than the current condition of this segment, it would be inappropriate to identify this segment as impaired.
5. Bear Creek segment 1a : This segment was proposed by the Division and by Trout Unlimited to be included on the Section 303(d) List. The evidence submitted demonstrated adverse impacts to the aquatic life use in this segment during 2002, and documented that the use had started to recover in 2003, although full recovery had not yet occurred. The evidence also demonstrated that the unusual and extreme drought conditions in 2002 were the determinative cause of the adverse impacts to aquatic life. Although there was evidence submitted indicating that ammonia concentrations or elevated temperatures may have adversely affected the aquatic life, the evidence demonstrated that these potentially harmful conditions would not have been present except for the drought. The Commission has concluded that this segment should be included on the Monitoring and Evaluation List for potential aquatic life, ammonia and temperature impairments, and that its status should be reconsidered in future updates of Regulations No. 93 and No. 94. Any evidence of impairment due to pollutants can be brought forth at the next listing hearing.
6. Lower Colorado segment 13b : This is an “all tributaries” segment that was proposed by the Division to be listed in its entirety for selenium. All of the ambient water quality data available in the record for this hearing was from tributaries on the north side of the Colorado River. In addition, there was testimony regarding significant differences in the geology on the north and south sides of the Colorado River in this area. Therefore, the Commission determined that it is appropriate that only the tributaries on the north side of this segment should be listed as impaired for selenium.
7. West Fork of Clear Creek, segment 5 : The Commission found that the acute zinc standard in the West Fork of Clear Creek was exceeded more than once in three years. Because the chronic zinc standard is in attainment, and because Climax presented credible biological evidence that the aquatic life use classification is supported, the Commission determined that listing for acute zinc is not warranted in this instance. This segment is included on the Section 303(d) List as impaired for copper.
8. Middle South Platte segment 1 : The Division proposed that the portion of this segment from Big Dry Creek to Highway 60 be included on the Section 303(d) List as impaired for dissolved oxygen during the months of August and September. The evidence submitted offered conflicting interpretations of what the available data for this segment show regarding attainment. Because this segment appears to be in compliance with dissolved oxygen standards based on the established convention of looking at the 15 th percentile of the available data for the entire segment, the Commission determined that it is more appropriate at this time to include this segment on the Monitoring and Evaluation List for further assessment of dissolved oxygen conditions. The Commission also believes that future clarification of the appropriate methodology for assessing attainment of dissolved oxygen standards, e.g. within specific months of the year, would be helpful.
F. Plans to Resolve Uncertainty Three parties presented plans to resolve uncertainty for segments that have temporary modifications based on uncertainty [see Regulation No. 31.7(3)(a)(iii)]. These segments will not be subject to the development of a TMDL as long as there is a plan in place that addresses the following:
1. Fountain Creek segment 6 (Monument Creek from the National Forest boundary to Fountain Creek) : The selenium water quality standard for Fountain Creek segment 6 has a temporary modification for uncertainty pursuant to section 31.7(3)(a)(iii) of the Basic Standards. The City of Colorado Springs submitted an appropriate plan to remove the uncertainty 2. Lower Arkansas segment 1a (Arkansas River from Fountain Creek to the Colorado Canal): The selenium water quality standard for Lower Arkansas segment 1a has a temporary modification for uncertainty pursuant to section 31.7(3)(a)(iii) of the Basic Standards. The City of Pueblo submitted an appropriate plan to remove the uncertainty 3. Upper Yampa segment 13d (Dry Creek): In the 2003 Upper Colorado River rulemaking hearing, the Commission adopted a temporary modification (based on uncertainty) of 60 ug/L for selenium in Dry Creek. This temporary modification was based on five WQCD samples collected in Dry Creek in 2001 and 2002 near its confluence with the Yampa River. The Commission approved Seneca Coal Company’s plan to monitor Dry Creek with the objective of determining the source or sources of selenium loading, where the loading is isolated in the lower portion of Dry Creek and to determine whether the loading is due to natural or irreversible man-induced sources.
93.11 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; FEBRUARY,
A. Introduction This regulation updates Colorado’s List of Water-Quality-Limited Segments Requiring Total Maximum Daily Loads (“TMDLs” ) to reflect additional water quality information available since the Regulation was promulgated in 2004. This list was prepared to fulfill section 303(d) of the federal Clean Water Act (“Act” ) which requires that states submit to the U.S. Environmental Protection Agency (“EPA” ) a list of those waters for which technology-based effluent limitations and other required controls are not stringent enough to implement water quality standards.
B. List Development 1. Listing Methodology The “Section 303(d) Listing Methodology - 2006 Listing Cycle” contains a description of the listing process, the criteria for listing, and the criteria for determination of TMDL priority. The Listing Methodology was developed through a public process and finalized as a policy at a Water Quality Control Commission administrative action hearing on May 9, 2005. This Listing Methodology sets forth the criteria that generally were used to make decisions regarding which waters to include on the 2006 Section 303(d) List and the 2006 M&E List. However, this methodology was not adopted by the Commission as a rule. The Commission therefore has the flexibility to take into account other appropriate factors in making site-specific listing decisions.
2. Information Considered The Commission has considered all existing and readily available information in developing the 2006 Section 303(d) List. In determining whether data and information are existing and readily available, it has taken into account such data and information as the Division has utilized in the preparation of those identification processes, calculations and models referenced in 40 CFR §130.7(a)(5)(i), (ii) and (iv) and that credible data and information presented in a readily usable format and submitted in reports provided to the Division as referenced in 40 CFR §130.7(a)(5)(iii). In addition, the Commission accepted credible data and information that was submitted in accordance with the listing process schedule, whether submitted by EPA or any other interested party. The Division also continues to independently collect and analyze new data on a rotating basin basis as part of its triennial review efforts and will utilize such data and information in making future listing determinations. Existing data which was not brought forward through one of the above mechanisms or otherwise presented to the Commission in accordance with the schedule was not treated as "readily available" for purposes of making the 2006 listing decisions. If submitted, such information will be considered in the next listing cycle.
C. Prioritization The objective of prioritization is to identify those waterbody segments where the Division and the public should concentrate their resources. Priorities of High, Medium and Low were established according to section IV. of the 2006 Section 303(d) Listing Methodology.
D. Temporary Modifications and Plans to Eliminate Uncertainty Consistent with the recent changes to the Basic Standards and Methodologies for Surface Water (Regulation No. 31) and the Discharge Permit Regulations (Regulation No. 61), the Commission deleted subsection 93.4 “Plans to Eliminate Uncertainty.” The Statement of Basis for the June 2005 rulemaking hearing for Regulation No. 31 states:
Consistent with this new approach to temporary modifications, the Commission intends that a more thorough consideration will be given to the causes and sources of non-attainment before temporary modifications are proposed. In cases where the appropriate way to address non-attainment of underlying standards is through the TMDL program, not through adoption of temporary modifications, the Commission may assign a higher TMDL priority to such waters.
E. Segment- Specific Issues Fountain Creek segment 2a: The Division had proposed inclusion of this segment due to non-attainment of the assigned E. coli standard. The Division noted that its proposal erroneously identified the listing as a “low” priority. The Section 303(d) Listing Methodology, 2006 Listing Cycle indicates that TMDLs for waters in non-support of Recreation 1a use classifications be designated as “high” priority. The Commission has therefore adopted a “high” priority designation for this segment. Fountain Creek segment 2b: This segment is the lowermost of three that comprise the mainstem of Fountain Creek. Both of the upper two segments are included on the List of Impaired Waters for E. coli. The Sierra Club had proposed that this lowermost segment should also be listed for E. coli. The Commission has decided that the Division’s analysis of the available data is consistent with the procedures contained in the Section 303(d) Listing Methodology, 2006 Listing Cycle and that the results of that analysis do not support inclusion of this segment on the Section 303(d) List of Water-Quality- Limited Segments Requiring TMDLs.
North Fork Gunnison River segment 6: The Division had proposed that this “all tributary” segment be listed in its entirety for non-attainment of the aquatic life use-based chronic selenium standard. The Colorado River Water Conservation District provided evidence that the standard is, in fact, attained at several locations within this segment. It is therefore appropriate that only that portion of the segment for which non-attainment has been documented be included on the list. The Commission has identified the affected portion of the segment as “Cottonwood Creek” and has revised the proposal accordingly. Uncompahgre River segment 6b (Red Mountain Creek): The Commission had in a February 2004 Rulemaking Hearing determined that there is not adequate data to support a finding of impaired Aquatic Life Use relative to the expected condition. Information offered in the 2006 hearing further reinforces this conclusion by demonstrating that the Commission’s classification assumes an extremely limited aquatic life use in this segment. In a rulemaking hearing scheduled for June 12, 2006, the Commission will consider a proposal to delete the aquatic life use classification for this segment. The Commission has therefore opted not to include Red Mountain Creek on the 2006 Section 303(d) List of Water-Quality- Limited Segments Requiring TMDLs.
Lower Gunnison segment 2: The Division proposed that this segment be listed for selenium and temperature, with a "high" priority for each. In view of evidence that it may be appropriate to reconsider the cold water aquatic life classification of this segment prior to initiating a TMDL, the Commission chose to change the priority for the temperature listing to "low". Lower Colorado River segment 3: The Division had initially proposed listing of this segment for ammonia. During discussions with the City of Grand Junction it was noted that during the course of the Division’s assessment an error had been made relative to the dataset utilized. The Division subsequently modified its proposal to withdraw this segment from its proposal. The Commission has not included the segment on the 2006 Section 303(d) List of Water-Quality-Limited Segments Requiring TMDLs.
Lower Colorado River segment 13a (Salt Creek): Salt Creek was proposed by the Division to be listed for sediment based upon a study of this and other tributary segments performed in conjunction with the BLM and Chadwick and Associates. Mesa County objected to the inclusion of Salt Creek on the Section 303(d) List of Water-Quality-Limited Segments Requiring TMDLs, arguing that the assessment protocols used were inconsistent with Commission Policy 98-1, the Implementation Guidance for Determining Sediment Deposition Impacts to Aquatic Life in Streams and Rivers. The assessment performed utilized the same approach embodied in the Sediment Guidance with respect to comparison of the affected reach to an expected condition. The validity of this comparative, expected condition analysis is not dependent on this being a high gradient, cobble bottom stream. The Commission has determined that the assessment adequately demonstrated non-attainment of the narrative sediment standard and consequent impairment of Salt Creek.
Bear Creek segment 1a: The Division proposed that this segment be retained on the Monitoring and Evaluation list for non-attainment of the assigned aquatic life use classification and for temperature. The evidence submitted demonstrated adverse impacts to trout populations at two stations (Bear Creek cabins and O’Fallon Park) situated in the upper reach of this segment since 2002 and documented that the use continued to recover well into 2004, although full recovery had not yet occurred. This evidence is consistent with the Commission’s conclusion in 2004 that the demonstrative cause of adverse impacts to aquatic life was the extreme drought in 2002. The 2006 Listing Methodology states that “Data collected during or immediately after temporary events influencing the waterbody that are not representative of normal conditions shall typically be discounted in making the listing decision.” Several parties argued that water quality conditions might have adversely affected the aquatic life. However, there was no evidence submitted demonstrating exceedance of the Mean Average Weekly Temperature criterion during 2004 or 2005, or demonstrating that impairment was otherwise caused by pollutants. The Commission has decided that the Division’s interpretation of the available data is consistent with the procedures contained in the Section 303(d) Listing Methodology, 2006 Listing Cycle and has determined that this segment should be retained on the Monitoring and Evaluation List for aquatic life impairments and temperature, and that its status should be reconsidered in future updates of Regulations No. 93 and No. 94.
The fact that impacts to Bear Creek aquatic life continue to appear to be related to the 2002 extreme drought is an adequate and appropriate basis for including this segment on the Monitoring and Evaluation List, rather than the Section 303(d) List. However, the Commission also notes that, even if continuing impacts did not appear to be tied to the drought, where there is no evidence that a numerical standard has been exceeded, the Commission’s practice has been to place waters on the Monitoring and Evaluation List if there is not evidence that a use impairment has been caused by a pollutant. The 2006 Listing Methodology states “Water bodies that are impaired but it is unclear whether the cause of impairment is attributable to pollutants as opposed to pollution will be placed on the M&E List.” EPA’s guidance for such circumstances differs. EPA’s guidance says that where there is an impairment but there has not been a demonstration that the impact is not caused by a pollutant, the water segment should be included on the Section 303(d) List. Because this provision appears in EPA guidance only, and the Commission is aware of no specific provisions of the Clean Water Act or EPA regulations that would dictate this result, the Commission believes that it has policy discretion to use different approach – i.e., to refrain from listing unless a pollutant has been identified as the cause of the use impairment. Clear Creek segment 13b (North Fork Clear Creek): The Division had proposed this segment be retained on the Section 303(d) List of Water-Quality-Limited Segments Requiring TMDLs for several parameters and for non-attainment of the assigned aquatic life use classification. The Commission has adopted this proposal, but notes that the segment attains the assigned numeric copper standard. The listing therefore does not include copper. Further, the Commission notes that the Division had proposed a “high” priority for completion of TMDLs for this segment, due to the fact that the North Fork of Clear Creek was included on the 1998 List of Impaired Waters and is therefore subject to provisions of the 1999 Settlement Agreement addressing TMDL development by the Division. The Commission has determined that a “medium” priority will be assigned for TMDL development, while recognizing that the Division remains obligated to completion of TMDLs for this segment by June 30, 2008. If the underlying standards are revised in the 2009 South Platte River basin rulemaking, TMDLs and/or Wasteload Allocations based on the superceded standards should be revisited. Cache la Poudre segment 14 (Horsetooth Reservoir): The Division proposed inclusion of Horsetooth Reservoir on the Section 303(d) List of Water-Quality-Limited Segments Requiring TMDLs due to non- attainment of the dissolved oxygen standard. Data for a ten-year period of record was found to be representative of conditions in the Reservoir. The Commission determined that in this instance it is appropriate to consider data for more than the most recent five years, in view of evidence that the most recent five years include a potentially unrepresentative period of reservoir drawdown. While the available data do not include samples spaced throughout a 24-hour period, the data are typical of that usually available for lakes and reservoirs. If diel variation were expected, it is likely that any such data would demonstrate a slight depression of dissolved oxygen concentration in the epilimnion during non-daylight hours. However, the area of non-attainment of dissolved oxygen in Horsetooth Reservoir is in the metalimnion, or middle layer of the reservoir. Testimony from Division staff indicated that it is unlikely that diel variation in dissolved oxygen levels would be expected in the metalimnion, since this deeper layer is unlikely to be affected by photosynthesis that occurs in the epiliminion. The Commission interprets the reference in the Listing Methodology to lake and reservoir samples representative of diel variation to apply only in those factual circumstances (e.g. dissolved oxygen in the epilimnion) where such variation would be expected.
The assessments and recommendations by the Division regarding Horsetooth Reservoir were consistent with the Section 303(d) Listing Methodology, 2006 Listing Cycle. However, the Commission notes that this hearing identified a need to provide further clarifications regarding appropriate procedures for assessing compliance with dissolved oxygen standards, particularly for lakes and reservoirs. The Commission encourages the Division to pursue such clarifications in preparation of the 2008 Listing Methodology, including, e.g., addressing variations in attainment status from year-to-year and further clarification of what constitutes representative data.
Evidence regarding the status of aquatic life in Horsetooth Reservoir does not override the fact that the data demonstrate a long term standards exceedance. The Commission’s practice has been to list waterbodies on the Section 303(d) List whenever representative data demonstrate non-attainment of a numerical standard, including dissolved oxygen. For other waters listed for non-attainment of dissolved oxygen, the Commission has not required evidence of the cause of the non-attainment. Although the provisions of the 2006 Listing Methodology arguably contain potentially conflicting language on this point, the Commission’s practice has not been to apply the provision regarding “water bodies that are impaired but it is unclear whether the cause of impairment is attributable to pollutants” to waters with dissolved oxygen impairments. Moreover, although the Commission was willing to consider listing Horsetooth Reservoir on the M&E List if the cause of the dissolved oxygen impairment was recent reservoir draw downs (i.e., reservoir operations), the evidence did not support this conclusion. Middle South Platte River segment 03a (Horse Creek Reservoir): The Division proposed that Horse Creek Reservoir be included on the Section 303(d) List of Water-Quality-Limited Segments Requiring TMDLs due to non-attainment of the assigned pH standard. The recommendation was based upon a representative dataset including four years of water quality monitoring results. The Commission has determined that inclusion of the Reservoir on the Section 303(d) List of Water-Quality-Limited Segments Requiring TMDLs for pH is appropriate and consistent with the Section 303(d) Listing Methodology, 2006 Listing Cycle. Dissolved oxygen data for the same four-year period demonstrate attainment of the dissolved oxygen standard. Although EPA questioned the Division’s current practice of averaging dissolved oxygen data within the sampling profile or profiles for a single sampling event, the Commission has determined that this practice is acceptable and appropriate, and consistent with the 2006 Listing Methodology. EPA’s proposal that Horse Creek Reservoir be listed for dissolved oxygen is based upon analytical procedures that are inconsistent with the Division’s current assessment practice. The Commission has determined that the Reservoir is not impaired with respect to the dissolved oxygen standard.
Upper Colorado River segment 07b (Muddy Creek): The Division had proposed the listing of Muddy Creek for non-attainment of the assigned temperature standard. The Colorado River Water Conservation District objected to the Division’s proposal and has provided evidence suggesting that the USGS sampling station (data from which formed the basis for the Division’s proposal) is situated such that any temperature data generated is likely not representative. The Commission has therefore included the segment on the 2006 Monitoring and Evaluation List to allow further examination of temperature data from this station.
Upper Yampa River segment 07b: This segment comprises a portion of the Yampa River mainstem. The Division had proposed that this segment be listed for temperature, again based upon USGS monitoring data. The Colorado River Water Conservation District provided evidence concerning the location of the USGS sampling station below the Steamboat Springs hot springs discharge. Again parties have agreed that such data is likely not representative of instream conditions. The Commission has placed the segment on the 2006 Monitoring and Evaluation List. Upper Yampa River segment 20 (First Creek, Elkhead Creek): These waters are classified for Recreation Use 1a, and are assigned a numeric E coli standard of 126 org./100 mL. Ambient E. coli levels exceed the assigned numeric standard. The U. S. Forest Service has raised concerns regarding the current assigned Recreation Use and the associated numeric standards. The Commission has included the segment on the 2006 Section 303(d) List of Water-Quality-Limited Segments Requiring TMDLs based upon the current classification and standards. However, it is the intent of the Commission that these issues be examined in the context of the 2008 Upper Colorado surface water standards rulemaking prior to the initiation of the TMDL development process. PARTIES TO THE RULEMAKING 1. The City of Grand Junction 2. The Colorado Division of Wildlife 3. Evergreen Trout Unlimited and Colorado Trout Unlimited 4. The City of Colorado Springs 5. The City of Black Hawk 6. The Colorado River Water Conservation District 7. Friends of Bear Creek 8. Big Thompson Watershed Forum 9. The Bear Creek Watershed Association 10. The Northern Colorado Water Conservancy District 11. U.S. Environmental Protection Agency, Region 8 12. Evergreen Metropolitan District and West Jefferson County Metropolitan District 13. USDA Forest Service, Medicine Bow-Routt National Forests 14. Colorado Rock Products Association 15. City and County of Broomfield 16. Climax Molybdenum Company 17. The Metro Wastewater Reclamation District 18. Mount Carbon Metropolitan District
93.12 STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; FEBRUARY,
A. Introduction This regulation updates Colorado’s List of Water-Quality-Limited Segments Requiring Total Maximum Daily Loads (“TMDLs” ) to reflect additional water quality information available since the Regulation was promulgated in 2006. This list was prepared to fulfill section 303(d) of the federal Clean Water Act (“Act” ) which requires that states submit to the U.S. Environmental Protection Agency (“EPA” ) a list of those waters for which technology-based effluent limitations and other required controls are not stringent enough to implement water quality standards.
B. List Development 1. Listing Methodology The “Section 303(d) Listing Methodology - 2008 Listing Cycle” contains a description of the listing process, the criteria for listing, and the criteria for determination of TMDL priority. The Listing Methodology was developed through a public process and finalized as a policy at a Water Quality Control Commission administrative action hearing on May 15, 2007. This Listing Methodology sets forth the criteria that generally were used to make decisions regarding which waters to include on the 2008 Section 303(d) List and the 2008 M&E List. However, this methodology was not adopted by the Commission as a rule. The Commission therefore has the flexibility to take into account other appropriate factors in making site-specific listing decisions.
2. Information Considered The Commission has considered all existing and readily available information in developing the 2008 Section 303(d) List. In determining whether data and information are existing and readily available, it has taken into account such data and information as the Division has utilized in the preparation of those identification processes, calculations and models referenced in 40 CFR §130.7(a)(5)(i), (ii) and (iv) and that credible data and information presented in a readily usable format and submitted in reports provided to the Division as referenced in 40 CFR §130.7(a)(5)(iii). In addition, the Commission accepted credible data and information that was submitted in accordance with the listing process schedule, whether submitted by EPA or any other interested party. The Division also continues to independently collect and analyze new data on a rotating basin basis as part of its triennial review efforts and will utilize such data and information in making future listing determinations. Existing data which was not brought forward through one of the above mechanisms or otherwise presented to the Commission in accordance with the schedule was not treated as "readily available" for purposes of making the 2008 listing decisions. Such information will be considered in the next listing cycle.
C. Prioritization The objective of prioritization is to identify those waterbody segments where the Division and the public should concentrate their resources. Priorities of High, Medium and Low were established according to section IV. of the 2008 Section 303(d) Listing Methodology.
D. Fish Consumption Advisory Listings Consistent with the 2008 Section 303(d) Listing Methodology, the Division proposed to include 12 segments on the 2008 303(d) List for non-attainment of the aquatic life use due to fish consumption advisories for mercury. The 2008 Section 303(d) Listing Methodology, states: Fish Consumption Advisories are issued by the Colorado Department of Public Health and Environment (“CDPHE” ) in instances where analysis of fish tissue samples provides documentation of a public health risk. Issuance of a FCA by CDPHE indicates impairment of an Aquatic Life Use classification for any waters so classified.
The 2006 303(d) List included three of these reservoirs for impairment due to mercury: one in the Rio Grande basin: Sanchez Reservoir (Rio Grande, segment 30), and two in the San Juan basin: McPhee Reservoir (Dolores, segment 4) and Narraguinnep Reservoir (La Plata, segment 11). These listing were changed by the Commission to specify that the listing was based on non-attainment of the aquatic life. This is consistent with the 2008 Listing Methodology and avoids confusion that there is non-attainment of the mercury standard in the water column.
The Commission has included 12 segments on the 2008 303(d) List for non-attainment of the aquatic life use due to mercury fish consumption advisories for 13 lakes or reservoirs. The Commission also included one listing based on non-attainment of the aquatic life use due to a PCE fish consumption advisory in Willow Springs Ponds, Fountain Creek, segment 7a.
E. Discussion of Issues Raised in the Hearing Dissolved Oxygen Standard in Lakes and Reservoirs : The issue of an appropriate D.O. standard in lakes and reservoirs was raised in this hearing by two parties, Northern and the River District. The River District focused its attention to high elevation lakes and reservoirs while Northern discussed the concept of representative data and assessment methods as outlined in the 2008 Listing Methodology. The Division agreed that work is needed to examine the D.O. standard for lakes and reservoirs and that additional refinement of the Listing Methodology is appropriate including consideration of whether and how refugia should be addressed. This standard is scheduled for review in preparation for the 2010 Basic Standards and Methodology, Regulation No. 31, RMH in June 2010. The Commission directs the Division to work with parties in 2008 and 2009 on any changes that are deemed appropriate for the 2010 Listing Methodology. The Commission made listing decisions based on the available data using the adopted standards and the 2008 Listing Methodology. Site-specific decisions made by the Commission are discussed below.
F. Segment- Specific Issues Fountain Creek segment 6, Monument Creek : Mainstem of Monument Creek from the boundary of National Forest Lands to the confluence with Fountain Creek: The Division had proposed retaining the portion of Monument Creek below Mesa Road on the 2008 303(d) List because selenium concentrations in that portion exceed the water quality standard for Fountain Creek Segment 6. The Commission has determined that it is appropriate at this time to include this portion of Monument Creek on the 2008 303(d) List. However, because there is an appropriate plan in place to address the segment as a whole, the Commission directs the Division and Colorado Springs Utilities to revisit this plan to determine the causes and potential reversal of elevated Se concentrations and the appropriate long-term underlying standard for this section of COARFO06.
Lower Colorado segment 2, Colorado River (COLCLC02): Mainstem of the Colorado River from Parachute Creek to the Gunnison River. The Division originally proposed listing this segment based on non-attainment of the selenium standard. The Division based its proposal on data from multiple sampling locations. The River District questioned whether some of the sample locations, including the Humphrey backwater location and others, were in the segment. The Division reviewed the sampling locations and determined that some of the sampling locations used in the original proposal were outside the segment. The segment was reassessed and still showed impairment. The parties disagree whether Humphrey Backwater is located within the segment but agreed that it demonstrated exceedences of the selenium standard. The Commission ultimately decided to list the Humphrey Backwater portion of the Colorado River segment based on those data, rather than listing the entire segment. White River segment 13b : Shell Frontier Oil and Gas Inc. provided additional analytical results for a number of locations within the Yellow Creek drainage. Re-assessment of several waters which had been proposed for inclusion on the Monitoring and Evaluation List indicated that Corral Creek, Box Elder Gulch, Stake Springs and Duck Creek, are all in attainment of the assigned standard for total recoverable iron. This additional data, however, also demonstrated that the lower portion of Corral Creek and Duck Creek are in non-attainment of the Aquatic Life Use-based chronic selenium standard. The Commission has added these waters to the 303(d) List for selenium.
Upper Colorado segment 5, Wolford Mountain Reservoir (COUCUC05) : The River District opposed the Division’s proposal to move Wolford Reservoir from the 2006 M&E List to the 2008 303(d) List when no additional data has been collected. In addition, the River District expressed their concerns with the current D.O. standard and Listing Methodology especially as it is applied to high alpine lakes and reservoirs. The Commission moved Wolford Reservoir from the M&E List to the 303(d) List based on the current standards and listing methods. The Commission has encouraged the Division, the River District and other parties to continue to work towards an improved D.O. standard for the 2010 Basic Standards Rulemaking Hearing. The Commission adopted a low priority for this listing, since it is appropriate for the D.O. standard and listing methodology issues to be addressed before substantial resources are expended on development of a TMDL.
Uncompahgre segment 14, Sweitzer Lake (COGUUN14) : The Division proposed listing for Sweitzer Lake due to exceedances of the D.O. standard in the mixed layer. The River District pointed out that there was no thermal stratification and adequate refugia present and therefore the segment should not be listed. They also indicated that there is evidence of chemical stratification. The Commission listed Sweitzer Lake, segment COGUUN14, on the 303(d) List due to exceedances in the mixed layer as defined in the Listing Methodology.
Upper Yampa segment 13d, Dry Creek (COUCYA13d): The Division proposed listing the Hubberson Gulch tributary of this segment due to non-attainment of the total recoverable iron standard. Seneca Coal Company (Seneca) provided evidence that the tributary is in attainment of the standard. The Commission did not list the segment for total recoverable iron on the 303(d) List. Upper Yampa segment 13e, Sage and Grassy Creeks (COUCYA13e): The Division proposed listing this segment due to non-attainment of the total recoverable iron and dissolved selenium standards. Seneca provided evidence that the total recoverable iron standard is attained within the segment. The Commission did not include the segment on the 303(d) List for total recoverable iron. Seneca also provided evidence that the selenium standard is attained in the upper portions of the two creeks in the segment. The Commission did include the lower portion of the creeks (Sage Creek below Routt County Road 51D and Grassy Creek below Routt County Road 27A), on the 303(d) List for dissolved selenium. PARTIES TO THE RULEMAKING HEARING 1. The Metro Wastewater Reclamation District 2. Bear Creek Watershed Association 3. Keystone Resort 4. City of Colorado Springs and Colorado Springs Utilities 5. CAM-Colorado LLC and CAM Mining LLC 6. Colorado Division of Wildlife 7. Southeastern Colorado Water Conservancy District 8. Shell Frontier Oil and Gas, Inc.
9. The Grand County Water and Sanitation District #1, the Winter Park West Water and Sanitation District, the Fraser Sanitation District and the Winter Park Sanitation District 10. Trout Unlimited, Colorado Trout Unlimited, and the Evergreen Chapter of Trout Unlimited 11. Northern Colorado Water Conservancy District 12. Seneca Coal Company 13 Colorado River Water Conservation District 14. U.S. Environmental Protection Agency, Region 8 15. City of Black Hawk and Black Hawk/Central City Sanitation District 16. Cripple Creek & Victor Gold Mining Company 17. Town of Minturn 18. Homestake Mining Company of California 19. CBS Operations Inc _____________________________________________________ Editor’s Notes History Entire Rule eff. 04/30/2008.