9 Va. Admin. Code § 25-31-165
A. Definitions. The following definitions apply specifically to this section:
"Annual mean flow" means the average of daily flows over a calendar year.
"Closed-cycle recirculating system" means a system designed, using minimized makeup and blowdown flows, to withdraw water from a natural or other water source to support contact and/or noncontact cooling uses within a facility. The water is usually sent to a cooling canal or channel, lake, pond, or tower to allow waste heat to be dissipated to the atmosphere and then is returned to the system. (Some facilities divert the waste heat to other process operations.) New source water (make-up water) is added to the system to replenish losses that have occurred due to blowdown, drift, and evaporation.
"Cooling water" means water used for contact or noncontact cooling, including water used for equipment cooling, evaporative cooling tower makeup, and dilution of effluent heat content. The intended use of the cooling water is to absorb waste heat rejected from the process or processes used, or from auxiliary operations on the facility's premises. Cooling water that is used in a manufacturing process either before or after it is used for cooling is considered process water for the purposes of calculating the percentage of a new facility's intake flow that is used for cooling purposes.
"Cooling water intake structure" means the total physical structure and any associated constructed waterways used to withdraw cooling water from state waters. The cooling water intake structure extends from the point at which water is withdrawn from the surface water source up to, and including, the intake pumps.
"Design intake flow" means the value assigned (during the facility's design) to the total volume of water withdrawn from a source water body over a specific time period.
"Design intake velocity" means the value assigned (during the design of a cooling water intake structure) to the average speed at which intake water passes through the open area of the intake screen (or other device) against which organisms might be impinged or through which they might be entrained.
"Entrainment" means the incorporation of all life stages of fish and shellfish with intake water flow entering and passing through a cooling water intake structure and into a cooling water system.
"Estuary" means a semi-enclosed body of water that has a free connection with open seas and within which the seawater is measurably diluted with fresh water derived from land drainage. The salinity of an estuary exceeds 0.5 parts per thousand (by mass) but is typically less than 30 parts per thousand (by mass).
"Existing facility" means any facility that is not a new facility.
"Freshwater river or stream" means a lotic (free-flowing) system that does not receive significant inflows of water from oceans or bays due to tidal action. For the purposes of this section, a flow-through reservoir with a retention time of seven days or less will be considered a freshwater river or stream.
"Hydraulic zone of influence" means that portion of the source water body hydraulically affected by the cooling water intake structure withdrawal of water.
"Impingement" means the entrapment of all life stages of fish and shellfish on the outer part of an intake structure or against a screening device during periods of intake water withdrawal.
"Lake or reservoir" means any inland body of open water with some minimum surface area free of rooted vegetation and with an average hydraulic retention time of more than seven days. Lakes or reservoirs might be natural water bodies or impounded streams, usually fresh, surrounded by land or by land and a man-made retainer (e.g., a dam). Lakes or reservoirs might be fed by rivers, streams, springs, and/or local precipitation. Flow-through reservoirs with an average hydraulic retention time of seven days or less should be considered a freshwater river or stream.
"Maximize" means to increase to the greatest amount, extent, or degree reasonably possible.
"Minimize" means to reduce to the smallest amount, extent, or degree reasonably possible.
"Natural thermal stratification" means the naturally-occurring division of a water body into horizontal layers of differing densities as a result of variations in temperature at different depths.
"New facility" means any building, structure, facility, or installation that meets the definition of a "new source" or "new discharger" and is a greenfield or stand-alone facility that commences construction after January 17, 2002, and uses either a newly constructed cooling water intake structure, or an existing cooling water intake structure whose design capacity is increased to accommodate the intake of additional cooling water. A greenfield facility is a facility that is constructed at a site at which no other source is located, or that totally replaces the process or production equipment at an existing facility. A stand-alone facility is a new, separate facility that is constructed on property where an existing facility is located and whose processes are substantially independent of the existing facility at the same site. New facility does not include new units that are added to a facility for purposes of the same general industrial operation (for example, a new peaking unit at an electrical generating station).
"Ocean" means marine open coastal waters with a salinity greater than or equal to 30 parts per thousand (by mass).
"Source water" means the water body from which the cooling water is withdrawn.
"Thermocline" means the middle layer of a thermally stratified lake or reservoir. In this layer, there is a rapid decrease in temperatures.
"Tidal excursion" means the horizontal distance along the estuary or tidal river that a particle moves during one tidal cycle of ebb and flow.
"Tidal river" means the most seaward reach of a river or stream where the salinity is typically less than or equal to 0.5 parts per thousand (by mass) at a time of annual low flow and whose surface elevation responds to the effects of coastal lunar tides.
B. Cooling water intake structures for new facilities.
1. Applicability.
a. This section applies to a new facility if it:
2. Compliance.
b. Track I requirements for new facilities that withdraw equal to or greater than 10 MGD. Facilities must comply with all of the following requirements:
(3) Design and construct the cooling water intake structure such that the total design intake flow from all cooling water intake structures meets the following requirements:
(4) Select and implement design and construction technologies or operational measures for minimizing impingement mortality of fish and shellfish if:
(5) Select and implement design and construction technologies or operational measures for minimizing entrainment of entrainable life stages of fish and shellfish if:
c. Track I requirements for new facilities that withdraw equal to or greater than two MGD and less than 10 MGD and that choose not to comply with subdivision 2 b of this subsection. Facilities must comply with all of the following requirements:
(2) Design and construct the cooling water intake structure such that the total design intake flow from all cooling water intake structures at the facility meets the following requirements:
(3) Select and implement design and construction technologies or operational measures for minimizing impingement mortality of fish and shellfish if:
d. Track II. The owner or operator of a new facility that chooses to comply under Track II must comply with the following requirements:
(2) Design and construct the cooling water intake structure such that the total design intake flow from all cooling water intake structures at the facility meet the following requirements:
3. Alternative requirements.
a. Any interested person may request that alternative requirements less stringent than those specified in 9VAC25-31-165 B 2 a through e be imposed in the permit. The department may establish alternative requirements less stringent than the requirements of 9VAC25-31-165 B 2 a through e only if:
4. Application information requirements.
a. The owner or operator of a new facility must submit to the department:
(1) A statement of intention to comply with either:
b. Track I application requirements. To demonstrate compliance with Track I requirements in 9VAC25-31-165 B 2 b or c, collect and submit to the department the information in subdivision 4 b (1) through (4) of this subsection.
(1) Flow reduction information. To comply with the flow reduction requirements in 9VAC25-31-165 B 2 b (1), submit the following information to demonstrate reduction of flow to a level commensurate with that which can be attained by a closed-cycle recirculating cooling water system:
(2) Velocity information. Submit the following information to demonstrate compliance with the requirement to meet a maximum through-screen design intake velocity of no more than 0.5 ft/s at each cooling water intake structure:
(3) Source water body flow information. Submit the following information to demonstrate that the cooling water intake structure meets the flow requirements in 9VAC25-31-165 B 2 b (3) and c (2):
(4) Design and Construction Technology Plan. To comply with 9VAC25-31-165 B 2 b (4) and (5), or 9VAC25-31-165 B 2 c (3) and (4), submit the following information in a Design and Construction Technology Plan:
c. Application requirements for Track II. In order to with the requirements of Track II in 9VAC25-31-165 B 2 d collect and submit the following information:
(1) Source water body flow information. Submit to the department the following information to demonstrate that the cooling water intake structure meets the source water body requirements in 9VAC25-31-165 B 2 d (2):
(2) Track II Comprehensive Demonstration Study. Perform and submit the results of a Comprehensive Demonstration Study (study). This information is required to characterize the source water baseline in the vicinity of the cooling water intake structure(s), characterize operation of the cooling water intake(s), and to confirm that the technology(ies) proposed and/or implemented at the cooling water intake structure reduce the impacts to fish and shellfish to levels comparable to those achieved by implementation of the requirements in 9VAC25-31-165 B 2 b (1) and (2) of Track I. To demonstrate the "comparable level" requirement, include information showing that:
(iv) A sampling plan for data that will be collected using actual field studies in the source water body. The sampling plan must document all methods and quality assurance procedures for sampling, and data analysis. The sampling and data analysis methods proposed must be appropriate for a quantitative survey and based on consideration of methods used in other studies performed in the source water body. The sampling plan must include a description of the study area (including the area of influence of the cooling water intake structure and at least 100 meters beyond); taxonomic identification of the sampled or evaluated biological assemblages (including all life stages of fish and shellfish); and sampling and data analysis methods; and
5. Monitoring. The owner or operator of a new facility will be required to perform monitoring to demonstrate compliance with the requirements specified in 9VAC25-31-165 B 2.
a. Biological monitoring. Monitor both impingement and entrainment of the commercial, recreational, and forage base fish and shellfish species identified in either the Source Water Baseline Biological Characterization data or the Comprehensive Demonstration Study, depending on whether compliance with Track I or Track II was chosen. The monitoring methods used must be consistent with those used for the Source Water Baseline Biological Characterization or the Comprehensive Demonstration Study. Follow the monitoring frequencies identified below for at least two years after the initial permit issuance.
6. Records and reporting. The owner or operator of a new facility is required to keep records and report information and data to the department as follows:
b. Provide the following to the department in a yearly status report:
C. Cooling water intake structures for existing facilities.
Existing facilities that are not subject to requirements under this section must meet requirements under section 316(b) of the Clean Water Act determined by the department on a case-by-case, best professional judgment (BPJ) basis.
§ 62.1-44.15 of the Code of Virginia; § 402 of the federal Clean Water Act; 40 CFR Parts 122, 123, 124, 403, and 503.
Derived from Virginia Register Volume 22, Issue 24, eff. September 6, 2006; amended, Virginia Register Volume 24, Issue 3, eff. November 14, 2007; Volume 39, Issue 4, eff. November 9, 2022.