Cooling Water Intake Structures

Transcription

1 Implementing CWA 316b - Lial Tischler Partner Tischler/Kocurek 3/8/16 Page 1

2 Introduction Final rule published in Federal Register August 15, 2014 (79 Fed. Reg 48300) Third phase of implementation of the statutory requirement for installation of Best Technology Available (BTA) for cooling water intake structures (CWIS) at Section 316(b) of the Clean Water Act (CWA). Regulations for BTA were adopted by the U.S. Environmental Protection Agency (EPA) pursuant to settlement of a lawsuit filed by the environmental groups (Riverkeeper Inc., et al.) in /8/16 Page 2

3 Introduction Implementation Schedule for Existing Facilities NPDES Permit applications submitted after 10/14/2014 Determination of rule applicability to the facility Selection of BTA method for impingement mortality Provide data for entrainment BTA determination: If actual intake flow (AIF) 125 million gallons/day (mgd), data is to support site-specific determination; If AIF > 125 mgd, provide entrainment studies required by 40 CFR (r)(9-13) Request alternate schedule for submittal of information in 40 CFR (r) 3/8/16 Page 3

4 Introduction Implementation Schedule for New Units at Existing Facilities Submit NPDES application 180 days before planned start-up NPDES application must include: Design intake flow for new unit must be consistent with closed-cycle recirculating cooling (CCRC), OR Alternative system must reduce adverse environmental impacts (AEI) that is consistent with CCRC, including demonstrating reduction in entrainment equal to or greater than 90% of that achieved by CCRC New CWIS facility standards must be met at start-up 3/8/16 Page 4

5 Introduction Out-of-scope CWIS at Existing Facilities If design intake flow (DIF) < 2 mgd and/or if cooling water use is <25% of intake flow: CWIS is subject to case-by-case permitting using best professional judgment (BPJ) in accordance with 40 CFR (b). BPJ is discretionary and permitting agency will determine application requirements (if any) and the permitting requirements based on site-specific information. 3/8/16 Page 5

6 Applicability Applicability at 40 CFR and special definitions at 40 CFR : Plant must be a point source subject to NPDES permitting requirements Water source is a Water of the United States (WOUS) CWIS draws water directly from a WOUS, or Water is purchased from an independent supplier that takes water directly from a WOUS 3/8/16 Page 6

7 Applicability Design intake flow (DIF) > 2 mgd and 25% or more is used for cooling this flow is cumulative for the entire CWIS Rule applicability is not limited to power stations and manufacturers [40 CFR (a) has no limitations on the definition of cooling water use] The definition of WOUS excludes groundwater sources from this rule. 3/8/16 Page 7

8 Applicability Exclusions Obtaining cooling water from a public water system, using reclaimed water from wastewater treatment facilities or desalination plants, or recycling treated process wastewater effluent as cooling water does not constitute use of a cooling water intake structure for purposes of this subpart. The rule does not apply to offshore seafood processing facilities, offshore liquefied natural gas terminals, and offshore oil and gas extraction facilities that are existing facilities as defined in (k). The owners and operators of such facilities must meet requirements established by the Director on a case-by-case, best professional judgment (BPJ) basis. 3/8/16 Page 8

9 Applicability Independent Supplier An entity, other than the regulated facility, that owns and operates its own cooling water intake structure and directly withdraws water from WOUS. The supplier provides the cooling water to other facilities for their use, but may itself also use a portion of the water. An entity that provides potable water to residential populations (e.g., public water system) is not a supplier for purposes of this rule. There remain unanswered questions about suppliers that are public agencies, e.g., San Jacinto River Authority, Coastal Water Authority, etc. 3/8/16 Page 9

10 Applicability Independent suppliers continued: Rule definition is silent on public agencies that supply water for multiple uses (e.g., irrigation, raw water for public water supplies, industrial water supply). Strict reading of the independent supplier definition would indicate that public entities that supply raw water to industry, municipalities and agriculture are not excluded from the CWIS rule. EPA s response to comments on this issue are ambiguous. Current status is likely to be case-by-case applicability determinations 3/8/16 Page 10

11 Applicability New units at existing facilities Existing facility means any facility that commenced construction as described in 40 CFR (b)(4) on or before 1/17/2002 (or 7/17/2006 for an offshore oil and gas extraction facility) and any modification of, or any addition of a unit at such a facility. A facility built adjacent to another facility would be a new facility while the original facility would remain as an existing facility for purposes of this subpart. A facility cannot both be an existing facility and a new facility as defined at /8/16 Page 11

12 Applicability New units at existing facilities: New unit means a new stand-alone unit at an existing facility where construction of the new unit begins after 10/14/2014 and that does not otherwise meet the definition of a new facility at or is not otherwise already subject to subpart I of the rule. A stand-alone unit is a separate unit that is added to a facility for either the same general industrial operation or another purpose. A new unit may have its own dedicated cooling water intake structure, or the new unit may use an existing or modified cooling water intake structure 3/8/16 Page 12

13 Applicability Evaluating applicability (assuming facility has or is required to have an NPDES permit, including a General Permit) Characterize the source of water supply. Determine if intake structure withdraws from a WOUS If purchased, determine if purveyor is an independent supplier or public water supply. Determine intake flow, if any, that is reclaimed/reused water Identify recycle/reuse of water streams within the facility (e.g., C/T blowdown used for desalter water) 3/8/16 Page 13

14 Applicability Evaluating applicability (continued) Identify and quantify ground water use, if any (e.g., groundwater used for cooling does not count as intake flow) Determine DIF based on pump capacity and AIF based on intake flow records. Perform water balance to determine the percent of intake water from WOUS or independent supplier that is used for cooling. Note: contact cooling (e.g. quench water) is not cooling water under this rule. 3/8/16 Page 14

15 BTA Overview CWIS facility characteristics determine BTA requirements 3/8/16 Page 15

16 BTA Standards Overview Requirements will be implemented in NPDES permits issued by delegated states or U.S. EPA Compliance schedules may be authorized for application submittal information/studies and for achieving compliance with the BTA Agencies can establish interim BTA requirements that apply during the compliance schedule The rule requirements acknowledge that for some facilities, full compliance may require more than one 5-year NPDES permit cycle. 3/8/16 Page 16

17 Impingement Mortality Impingement is the entrapment of any 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. Impingement includes those organisms collected or retained on a sieve with maximum distance in the opening of 0.56 inches, and excludes those organisms that pass through the sieve. This definition is intended to prevent the conversion of entrainable organisms to counts of impingement or impingement mortality. The owner or operator of a facility must use a sieve with the same mesh size when counting entrainment as is used when counting impingement. 3/8/16 Page 17

18 Impingement BTA BTA standards for impingement mortality are at 40 CFR (c) There are seven alternatives for compliance with this BTA standard: Closed-cycle recirculating system (CCRS) Screen design/operating limits (5 options) Systems of technologies Performance standard De minimis impingement rate demonstration Additional measures may be required for shellfish and other species (fragile species as defined in the rule or by the regulatory agency) 3/8/16 Page 18

19 Impingement BTA Standards Closed-cycle recirculating systems (c)(1): A system designed and properly operated using minimized make-up and blowdown flows withdrawn from a water of the United States to support contact or non-contact cooling uses within a facility, or a system designed to include certain impoundments. A closed-cycle recirculating system (CCRS) passes cooling water through the condenser and other components of the cooling system and reuses the water for cooling multiple times. 3/8/16 Page 19

20 Impingement BTA Standards The CCRS definition includes: A facility with wet, dry, or hybrid cooling towers, a system of impoundments that are not waters of the United States, or any combination thereof. A properly operated and maintained CCRS withdraws new source water (make-up water) only to replenish losses that have occurred due to blowdown, drift, and evaporation. A system with impoundments of WOUS where the impoundment was constructed prior to October 14, 2014 and created for the purpose of serving as part of the cooling water system. 3/8/16 Page 20

21 Impingement BTA Standards CCRS Compliance requirements: Must monitor intake flow at a minimum frequency of daily (does not require continuous monitoring) Operating data must be representative of normal operation and include: Withdrawal from WOUS Make-up flow, and Blowdown flow Alternatively, cycles of concentration can be measured on a daily frequency (e.g., can use daily samples of make-up and blowdown TDS, chlorides, etc.) 3/8/16 Page 21

22 Impingement BTA Standards 0.5 Feet Per Second Through-Screen Design Velocity (c)(2). Maximum design intake velocity as water passes through the structural components of a screen measured perpendicular to the screen mesh does not exceed 0.5 feet per second. The maximum velocity standard must be achieved under all conditions, including during minimum ambient source water surface elevations and during periods of maximum head loss across the screens or other devices during normal operation of the intake structure. Note: the standard does not actually require the use of a screen [see language at (c)(3)] 3/8/16 Page 22

23 Impingement BTA Standards 0.5 Feet Per Second Through-Screen Actual Velocity (c)(3). The facility must demonstrate that the maximum intake velocity as water passes through the structural components of a screen measured perpendicular to the screen mesh does not exceed 0.5 feet per second. The maximum velocity standard must be achieved under all conditions, including during minimum ambient source water surface elevations normal operation of the intake structure. Short-term deviations for maintenance are allowed if authorized. If the intake does not have a screen, the maximum intake velocity perpendicular to the opening of the intake must not exceed 0.5 feet per second at minimum ambient source water surface elevations 3/8/16 Page 23

24 Impingement BTA Standards Modified traveling screens (c)(5). a traveling water screen that incorporates measures protective of fish and shellfish. Examples of modified traveling screens include, but are not limited to: Modified Ristroph screens with a fish handling and return system, dual flow screens with smooth mesh, and rotary screens with fish returns or vacuum returns. The applicant must provide the impingement technology performance optimization study specified at 40 CFR (r)(6)(i), The regulatory agency determines if the screen is the BTA for impingement reduction at the site. 3/8/16 Page 24

25 Impingement BTA Standards Systems of technologies as the BTA for impingement mortality (c)(6). A system of technologies, management practices, and operational measures, that, after review by the agency is determined to be BTA. The impingement technology performance optimization study specified at 40 CFR (r)(6)(ii) must be provided by the facility to support the BTA determination. Technology must minimize impingement mortality for all non-fragile species 3/8/16 Page 25

26 Impingement BTA Standards Impingement mortality performance standard (c)(7). A facility must achieve a 12-month impingement mortality performance standard of all life stages of fish and shellfish of no more than 24 percent mortality, including latent mortality, for all non-fragile species together that are collected or retained in a sieve with maximum opening dimension of 0.56 inches and kept for a holding period of 18 to 96 hours. Biological monitoring must be conducted at a minimum frequency of monthly to demonstrate impingement mortality performance An alternative monitoring period may be specified by the agency 3/8/16 Page 26

27 Impingement BTA Standards (c)(8) Additional measures for shellfish. The owner or operator must comply with any additional measures, such as seasonal deployment of barrier nets, established by the agency to protect shellfish (c)(9) Additional measures for other species. The owner or operator must comply with any additional measures, established by the agency, to protect fragile species (c)(10) Reuse of other water for cooling purposes. The impingement mortality standard does not apply to that portion of cooling water that is process water, gray water, waste water, reclaimed water, or other waters reused as cooling water in lieu of water obtained by marine, estuarine, or freshwater intakes. 3/8/16 Page 27

28 Impingement BTA Standards De minimis rate of impingement (c)(11). Agency can determine that rates of impingement are so low that no additional controls are required. Determination is made on site-specific data supplied in the permit application as specified at 40 CFR (r). No take of threatened or endangered species is authorized. Draft permit and fact sheet must notify the public of the proposed de minimis impingement determination. 3/8/16 Page 28

29 Entrainment BTA Standards Entrainment means any life stages of fish and shellfish in the intake water flow entering and passing through a cooling water intake structure and into a cooling water system, including the condenser or heat exchanger. Entrainable organisms include any organisms potentially subject to entrainment. For purposes of this subpart, entrainment excludes those organisms that are collected or retained by a sieve with maximum opening dimension of 0.56 inches. 3/8/16 Page 29

30 Entrainment BTA Standards BTA standards for entrainment for existing facilities (d). The NPDES permitting agency must establish BTA standards for entrainment for each intake on a site-specific basis. The BTA standards must reflect the agency's determination of the maximum reduction in entrainment warranted after consideration of the relevant factors as specified in Periodic reporting may be required to describe progress towards installation and operation of site-specific entrainment controls. These reports may include updates on planning, design, and construction or other appropriate topics as required by the agency. 3/8/16 Page 30

31 Entrainment BTA Standards BTA standards for entrainment for existing facilities (d) (cont.) The agency may determine that the site-specific BTA standard for entrainment requires performance equivalent to a closed-cycle recirculating system as defined at (c)(1). This provision supports a default determination that a system that uses CCRS complies with the entrainment standard. Entrainment requirements may also reflect any control measures to reduce entrainment of Federally-listed threatened and endangered species and designated critical habitat (e.g. prey base). 3/8/16 Page 31

32 Entrainment BTA Standards BTA standards for impingement mortality and entrainment for new units at existing facilities (e) The facility must reduce the DIF for the new unit, at a minimum, to a level commensurate with that which can be attained by the use of a CCRS for the same level of cooling for the new unit [ (e)(1)], or The facility must demonstrate that the technologies and operational measures employed will reduce the level of adverse environmental impact from any CWIS used to supply cooling water to the new unit comparable to the entrainment reduction that would be achieved by use of a CCRS. 3/8/16 Page 32

33 Entrainment BTA Standards Summary of entrainment requirements for new units at existing facilities: For all practical purposes, if a new unit is being constructed at an existing facility, cooling should either be provided by a CCRS or by a method exempted from the rule (e.g., reuse, groundwater, etc.) Demonstration and approval of alternate entrainment controls will be difficult because the permitting agency has considerable discretion in making the BTA determination. 3/8/16 Page 33

34 NPDES Permit Applications CWIS information and data are to be included in NPDES permit applications. All facilities with an in-scope CWIS must file all information identified in 40 CFR (r)(1) that applies to them with permit applications submitted after 10/14/2014 Some states have developed specific forms and formats for submittal of CWIS information. U.S. EPA does not have CWIS NPDES application forms. 3/8/16 Page 34

35 NPDES Permit Applications Application Requirements Include: Source water physical data Cooling water intake structure data Source water baseline biological characterization data Cooling water system data Chosen method for compliance with impingement BTA Entrainment performance study (once-through systems) 3/8/16 Page 35

36 NPDES Permit Applications Application Requirements Include (continued): Operational status Entrainment characterization study (once-through systems) Comprehensive technical feasibility and cost evaluation study (oncethrough systems with DIF >125 mgd) Benefits valuation study (once-through systems with DIF >125 mgd) Non water quality environmental and other impacts study (once-through systems with DIF >125 mgd) 3/8/16 Page 36

37 TischlerKocurek 107 South Main Street Round, Rock TX /8/16 Page 37