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HomeMy WebLinkAboutNC0089699_Review of 316 (b) Dan River Inkae_20170615Water Resources Environmental Quality June 15th, 2017 Teresa Rodriguez NPDES Unit Subject Review of 316(b) Dan River Intake Rockingham County, NC Dear Teresa ROY COOPER Coves nor MICHAEL S. REGAN Secretary S. JAY ZIMMERMAN Derectol Jeff DeBerardinis and Eric Fleek from the Water Sciences Section (WSS) staff have reviewed the germane fish and benthos data for the subject reach of the Dan River Specifically, as it relates to the proposed installation and operation of the new intake Based on this review, we do not have any significant objections or concerns at this time Additionally, there are long-term benthos and fish datasets available in this area and any deleterious impacts that may arise to these communities due to operation of the new intake may be detected In this event, the Department should reserve the right to modify the permit accordingly Please do not hesitate to contact me or my staff if you should have any comments or concerns Sincerely, 4-/" Cyndi Karoly Chief, Water Sciences Section Nothing Compares�-, State of North Carolina I Environmental Quality / Water Sciences Section 1621 Mail Service Center I Raleigh, North Carolina 27699-1621 919-743-8400 ROY COOPER Goremoj ,o Water Resources ENVIRONMENTAL QUALITY MEMORANDUM May 9, 2017 To: Cyndi Karoly, Section Chief Water Science Section From: Teresa Rodriguez 919-807-6387 NPDES Unit Subject: 316(b) Report Rockingham County MICHAEL S REGAN Sea e(ai P S JAY ZIMMERMAN Du ectoi The NPDES received a new application for a proposed natural gas -fired combined cycle electric generating facility that falls under the requirements of CWA Section 316(b). A new intake structure is proposed on the Dan River in Rockingham County. The NPDES Complex permitting Branch is requesting the review of the application documents pertaining to the evaluation of the Biological Characterization Data included in the application. State of North Carolina I Environmental Quality I Water Resources 1617 Mail Service Center I Raleigh, North Carolina 27699-1617 919 807 6300 Water Resources ENVIRONMENTAL QUALITY MEMORANDUM May 9, 2017 To: Cyndi Karoly, Section Chief Water Sciences Section From: Teresa Rodriguez 919-807-6387 NPDES Unit Subject: 316(b) Report Rockingham County ROY COOPER Govemoi MICHAEL S REGAN Sect eiai7, S JAY ZIMMERMAN Du ectoi The NPDES received a new application for a proposed natural gas -fired combined cycle electric generating facility that falls under the requirements of CWA Section 316(b). A new intake structure is proposed on the Dan River in Rockingham County. The NPDES Complex permitting Branch is requesting the review of the application documents pertaining to the evaluation of the Biological Characterization Data included in the application. �f has I (�� ) - om:�,w (dm RECEIVED MAY 1 12017 Water Sciences Section State of North Carolina ,� Environmental Quality I Water Resources 1617 Mail Service Center I Raleigh, North Carolina 27699-1617 919 807 6300 ,=Cj,- Environmental Consulting & Technology of North Carolina, PLLC RECEIVEDINCDEQIDWR APR 2 7 2017 Water UUaUty Permitting Section APPENDIX D 316(b) (r) REPORTS N \PRJ\NTE ENERGY\LKC NPDES\,IENIO\NTE NPDES NARRATIVE FINAL DOC\ Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance per 40 CFR 122.21(r) and 125.86(b) Rockingham County, NC April 2017 CG7 No 170030 Rockingham County Table of Contents Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Section Page 1.0 Introduction 1-1 1.1 Project Background 1-1 1.2 Regulatory Background 1-3 2.0 Source Water Physical Data [40 CFR 122.21(r)(2)] 2-1 2.1 Description of Source Water Body [40 CFR 122.2 1 (r)(2)(i)] 2-1 2.2 Characterization of Source Water Body [40 CFR 122.2 1 (r)(2)(ii)] 2-5 2.2.1 Hydrology 2-5 2.2.2 Geomorphology 2-5 2.2.3 Determination of Area of Influence 2-6 2.3 Locational Maps [40 CFR 122.21(r)(iii)] 2-8 3.0 Cooling Water Intake Structure Data [40 CFR 122.21(r)(3)] 3-1 3.1 Narrative Description of CWIS [40 CFR 122.21(r)(3)(i)] 3-1 3.2 Latitude and Longitude of CWIS [40 CFR 122.2 1 (r)(3)(ii)] 3-8 3.3 Description of CWIS Operation [40 CFR 122.21(r)(3)(iii)] 3-8 3.4 Intake Flow [40 CFR 122.2 1 (r)(3)(iv)] 3-8 3.5 Engineering Drawings of CWIS [40 CFR 122.21(r)(3)(v)] 3-10 4.0 Source Water Baseline Biological Characterization Data [40 CFR 122.21(r)(4)] 4-1 4.1 List of Unavailable Biological Data [40 CFR 122.21(r)(4)(i)] 4-1 4.2 List of Species and Relative Abundance in the Vicinity of CWIS L40 CFR 122.21(r)(4)1 4-1 4.2.1 Rhode et al Studies 4-2 4.2.2 NC Wildlife Resources Commission 4-2 4.2.3 Duke Energy 4-2 4.3 Identification of Species and Life Stages Susceptible to I and E LO CFR 122.21(r)(4)(iii)l 4-5 N \PRANTE ENERGY\LKC NPDES\R REPORTSIR REPORTS O42017 DOCX 1 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 4.4 Identification and Evaluation of Primary Growth Period 4f 0 CFR 122.21(r)(4)(iv)l 4-12 4.4.1 Reproduction 4-12 4.4.2 Larval Recruitment and Period of Peak Abundance 4-12 4.5 Data Representative of Seasonal and Daily Activities of Organisms in the Vicinity ofCWIS [40 CFR 122.21(r)(4)(v)] 4-13 4.6 Identification of Threatened, Endangered, and Other Protected Species Susceptible to I and E at CWIS r40 CFR 122 21(r)(4)(ivll 4-13 4.7 Documentation of Consultation with Services [40 CFR 122.21(r)(4)(vii)] 4-18 4.8 Methods and Quality Assurance Procedures for Field Efforts NO CFR 122 21(r)(4)(viii)] 4-18 4.9 Definition of Source Water Baseline Biological Characterization Data [40 CFR 122.21(r)(4)(ix)] 4-18 4.10 Identification of Protective Measures and Stabilization Activities LO CFR 122.21(r)(4)(x)l 4-19 4.11 List of Fragile Species [40 CFR 122.2 1 (r)(4)(xi)] 4-19 4.12 Information Submitted to Obtain Incidental Take Exemption or Authorization from Services [40 CFR 122.21(r)(4)(xii)] 4-20 N IPRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 11 ��, Rockingham County List of Tables Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table Page 1 Review of Proposed Intake Relative to the Requirements of 40 CFR 125.84(a)(1) 1-4 2 Review of Proposed Intake Relative to the Requirements of 40 CFR 125.86(b) 1-7 3 Impairments and Appropriate Uses of Waters of Dan River within Vicinity of CWIS 2-5 4 Summary of Dan River Fish Survey Results with Relative Abundance 4-3 5 Potential for Impingement and Entrainment of Fish Species Located within the Vicinity of the Proposed CWIS 4-6 6 Seasonal and Daily Activities of Fish Species Located within the Vicinity of the Proposed CWIS 4-8 7 List of State and Federally Protected Species Potentially Occurring in the Vicinity of the Proposed CWIS 4-16 8 Protected Aquatic Species Range and Reproductive Habits 4-17 N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX III M Ar Rockingham County List of Figures Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Fi ure 1 Site Location, Intake, and Discharge Overview 2 Raw Water Intake and Pump Station Site Plan 3 Discharge Location 4 Proposed Cooling Water Intake Screen Design 5 Preliminary Water Balance Diagram 6 Preliminary Water Balance — Water Use Scenarios Page 1-2 2-2 2-3 3-3 3-5 3-6 N \PRANTE ENERGY\LKC NPDESa REPORTS\R REPORTS O42017 DOCX Iv AM I Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 1.0 Introduction 1.1 Proiect Background This report has been prepared to address relevant sections of the Code of Federal Regulations (CFR), Title 40, Parts 122.21(r) and 125.85(b), of the Clean Water Act Section 316(b) rule for new facilities (Phase I of the rule; Federal Register [FR] Volume 66, pp. 65337-65345, as amended). Section 316(b) requires the location, design, construction, and capacity of cooling water intake structures (CWISs) reflect the best technology available for minimizing adverse environmental impact. Phase I of the rule applies to new facilities required to have a National Pollutant Discharge Elimination System (NPDES) permit that have a CWIS with a design capacity greater than or equal to 2 million gallons per day (MGD), and use at least 25 percent of the water withdrawn for cooling purposes. The Rockingham County Department of Engineering & Public Utilities (Rockingham County) is proposing to provide water and wastewater services to the proposed Reidsville Energy Center, a natural gas -fired combined cycle electric generating facility in Rockingham County, North Carolina, herein referred to as the "Project" The proposed Project will be constructed approximately 9 miles west of Reidsville, North Carolina, along Highway 65 (Figure 1) and will consist of one combustion turbine with supplementary duct firing. The exhaust heat from the combustion turbine and the supplemental duct firing will be captured and converted to steam in a heat recovery steam generator (HRSG) before passing through a steam turbine to generate additional power. The Project will provide the benefit of local power generation from a reliable, environmentally responsible fuel source Combined -cycle plants have the ability to start up quickly and vary generation to match load conditions, making this type of plant a good complement to renewable generation such as solar or wind. Rockingham County intends to withdraw up to 4.194 MGD from an intake and pump station located on the Dan River for cooling and process water (Figure 1). � � N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 1' 1 A , N r)p I\. T P r I,—, "I S " n t T;- —. I n , P —ri ---H , All —,I)r) 17 ') A 1 f) I PKA 4 0 2,000 41000 V Feet 4A !r/ Proposed perDischarge Location 7 r River,` V, —V r 01- A -1 LAI- V 4 e.;rp Proposed JA Intake Location 7 V "1 7n \l 4 -C e0- 03 1# V 4� W" -A BE J0 C Legend Discharge Pipeline A Intake Pipeline % C Project Area 1: A , FIGURE I SITE LOCATION, INTAKE, AND DISCHARGE OVERVIEW Environmental Consulting & Technology of North Carolina, PLLC Sources LIDAR Contours, 2007, ESRI World Imagery, NAIP, 2014 ECT 2016 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 1.2 Regulatory Background The U.S. Environmental Protection Agency (EPA) promulgated the Phase I rule for regulation of new facilities under Section 316(b) on December 18, 2001, and these rules became effective on January 17, 2002, with minor amendments made to the rule in July 2003. The Phase II rule (for existing facilities) was published on July 9, 2004 (69 FR 41576) but withdrawn in 2007; the reissued final 316(b) rule for existing facilities (79 FR 48300) became effective on October 14, 2014. The final rule supersedes the Phase II rule, the remanded existing facility portion of the previously promulgated Phase III rule, and includes minor amendments to the Phase I rule. The 316(b) Phase I rule requires each affected facility's application for an NPDES discharge' permit include specific submittals and supporting information to demonstrate compliance with the rule's performance standards. Facilities such as the proposed Project are required to submit a set of documents with their NPDES application to establish compliance with 40 CFR 122.21(r)(2) through (4): (2) Source Water Physical Data (3) Cooling Water Intake Structure Data (4) Source Water Baseline Biological Characterization This document addresses the requirements for these three reports in the following three sections. Rockingham County anticipates peak withdrawals of 4.194 MGD and is therefore seeking to comply under the rule's "Track I" as defined at 40 CFR 125.84(c). Section 3.1 summarizes the proposed intake's compliance with the criteria defined at this section of the rule (see 40 CFR 125.86(b) for Track I application requirements). Tables 1 and 2 provide a summary of how the proposed project addresses the requirements of 40 CFR 125.84(a)(1) and 125.86(b), respectively, including cross-references to the relevant sections of the following report The Phase I rule also requires the applicant to summarize how the proposed cooling system and intake will comply with the requirements of the rule. The information required is contained in Sections 2, 3, and 4 of this report per the specifications of 40 CFR 122.21(r). A�C,� N \PRANTE ENERGYU.KC NPDES\R REPORTS\R REPORTS O42017 DOCX 1-3 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 1. Review of Proposed Intake Relative to the Requirements of 40 CFR 125.84(a)(1) § 125.84 As an owner or operator of a new facility, what must I do to comply with this subpart? (a)(1) The owner or operator of a new facility must comply with either (i) Track I in paragraph (b) or (c) of this section, or (n) Track 11 in paragraph (d) of this section (2) In addition to meeting the requirements in paragraph (b), (c), or (d) of this section, the owner or operator of a new facility may be required to comply with paragraph (e) of this section (c) Track 1 requirements for new facilities that withdraw gi eater than 2 MGD and less than 10 MGD and that choose not to comply with paragraph (b) of this section You must comply with all of the following requirements Subsection Notes on Rockingham County's Approach (1) You must design and construct each cooling water The facility's cooling water intake will be designed to achieve intake structure at your facility to a maximum through- through -screen velocities of less than 0 5 fps screen design intake velocity of 0 5 fps, (2) You must design and construct your cooling water intake structure such that the total design intake flow from all cooling water intake structures at your facility meets the following requirements (i) For cooling water intake structures located in a freshwater The proposed intake is located in a freshwater river The river or stream, the total design intake flow must be no proposed total design intake flow is 0 63 percent of the greater than five (5) percent of the source water annual mean average mean flow as estimated from 17 years of annual flow flow, record for the Dan River near Wentworth, North Carolina, located just downstream of the intake (ii) For cooling water intake structures located in a lake or Not applicable reservoir, the total design intake flow must not disrupt the natural thermal stratification or turnover pattern (where present) of the source water except in cases where the disruption is determined to be beneficial to the management of fisheries for fish and shellfish by any fishery management agency(ies), (in) For cooling water intake structures located in an estuary Not Applicable or tidal river, the total design intake flow over one tidal cycle of ebb and flow must be no greater than one (1) percent of the volume of the water column within the area centered about the opening of the intake with a diameter defined by the distance of one tidal excursion at the mean low water level, (3) You must select and implement design and construction The proposed intake location potentially meets at least one of technologies or operational measures for minimizing the criteria defined below [i e , (4)(1)] Flow reduction from impingement mortality of fish and shellfish if the use of closed -cycle cooling, along with wedgewire screens with a through -screen velocity less than 0 5 fps, will minimize impingement mortality of fish and shellfish A�C� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 1-4 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Table 1. Review of Proposed Intake Relative to the Requirements of 40 CFR 125.84(a)(1) (i) There are threatened or endangered or otherwise protected federal, state, or tribal species, or critical habitat for these species, within the hydraulic zone of influence of the cooling water intake structure, or (n) There are migratory and/or sport or commercial species of impingement concern to the Director or any fishery management agency(ies), which pass through the hydraulic zone of influence of the cooling water intake structure, or (m) It is determined by the Director or any fishery management agency(ies) that the proposed facility, after meeting the technology -based performance requirements in paragraphs (c)(1) and (c) (2)of this section, would still contribute unacceptable stress to the protected species, critical habitat of those species, or species of concern, (4) You must select and implement design and construction technologies or operational measures for minimizing entrainment of entrainable life stages of fish and shellfish The intake is located in an area that may support listed species, including the Roanoke logperch and James spinymussel However, as discussed in Section 4 6, species - specific habitat preferences may reduce the potential for interaction with the intake Given the Project's use of closed -cycle recirculating cooling system and the protective design of the intake, it is believed unlikely that any listed species would be subject to substantive effects from impingement Migratory, sport, and/or commercial species may be present near the intake, however, the size of the hydraulic zone of influence is very small and its location along the bank and low through -screen velocity strongly suggests that fish would be able to avoid impingement The use of closed -cycle cooling and side bank wedgewire screen intake design should be protective of any species of concern or critical habitat Rockingham County will coordinate with NC Wildlife Resources Commission (WRC) and U S Fish and Wildlife Service (USFWS) to ensure that the intake will not contribute unacceptable stress to protected species, species of concern, or critical habitat Flow reduction from the use of closed -cycle cooling, along with wedgewire screens with a through -screen velocity no greater than 0 5 fps, will minimize entrainment of fish and shellfish including protected species (5) You must submit the application information required in The relevant information required at 40 CFR 122 21(r) and 40 CFR 122 21(r) and § 125 86(b)(2), (3), and (4), 125 86(b)(2), (3), and (4) is provided in this document (6) You must implement the monitoring requirements specified in § 125 87, (7) You must implement the recordkeepmg requirements specified in § 125 88 N \PRANTE ENERGIILKC NPDES\R REPORTMR REPORTS O42017 DOCX 1-5 The Project exceeds the Phase I rule requirements for facilities withdrawing between 2 and 10 MGD of cooling water by incorporating closed -cycle cooling and by employing wedgewire screens that essentially eliminate impingement but are not amenable to quantitative _ impmgem_`ent s_amphng(as is typically performed on intakes with traveling screens) Rockingham County believes that its use of these technologies (considered best technology available (BTA) for both impingement mortality and entrainment mortality under other aspects of the 316(b) rule) eliminates the need for biological monitoring that would be required under § 125 87(a) Rockingham County believes that flow monitoring and periodic inspection of the screen surfaces would is sufficient to comply with the velocity monitoring requirements in § 125 87(b) and (c) Rockingham County will comply with the rule's recordkeepmg and reporting requirements as stipulated in the Project's NPDES permit Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Table 1. Review of Proposed Intake Relative to the Requirements of 40 CFR 125.84(a)(1) § 125 84(e) You must comply with any more stringent requirements relating to the location, design, construction, and capacity of a cooling water intake structure or monitoring requirements at a new facility that the Director deems are reasonably necessary to comply with any provision of state law, including compliance with applicable state water quality standards (including designated uses, criteria, and antidegradation requirements) Source Rockingham County, 2017 § 125 84(a)(2) states that "a new facility may be required to comply with paragraph (e) of this section" [emphasis added] The riverbank location has been selected to avoid known critical oo unique aquatic or shoreline habitats fEW-0_ject d'esign`ezceeds the Phase I "rule requirements for facilities withdrawing between 2 and 10 MGD of cooling water by incorporating closed -cycle cooling and incorporating wedgewue screens Construction impacts will have a minimal footprint and will not impact water quality or designated uses Additional requirements are therefore not anticipated Should additional requirements be deemed necessary, Rockingham County will review them and reserves the right to suggest alternative approaches to addressing any potential concerns by the Director �C� N TRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 1-6 1 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Table 2. Review of Proposed Intake Relative to the Requirements of 40 CFR 125.86(b) § 125.86 As an owner or operator of a new facility, what must I collect and submit when I apply for my new or reissued NPDES permit? (a)(1) As an owner or operator of a new facility, you must submit to the Director a statement that you intend to comply with either (i) The Track I requirements for new facilities that withdraw equal to or greater than 10 MGD in § 125 84(b), (ii) The Track I requirements for new facilities that withdraw greater than 2 MGD and less than 10 MGD in § 125 84(c), (ui) The requirements for Track II in § 125 84 (d) (2) You must also submit the application information required by 40 CFR 122 21(r) and the information required in either paragraph (b) of this section for Track I or paragraph (c) of this section for Track II when you apply for a new or reissued NPDES permit in accordance with 40 CFR 122 21 (b) Track I application requirements To demonstrate compliance with Track I requirements in § 125 84(b) or (c), you must collect and submit to the Director the information in paragraphs (b)(1) through (4) of this section Subsection Notes and References to Later Report Sections (1) Flow reduction information If you must comply with the flow Not applicable However, the facility will employ closed - reduction requirements in § 125 84(b)(1), you must submit the cycle recirculating cooling using mechanical evaporative following information to the Director to demonstrate that you have cooling towers Make-up flows have been minimized subject reduced your flow to a level commensurate with that which can be to the cooling and process water needs of the plant attained by a closed -cycle recirculating cooling water system Blowdown flows have been minimized subject to water quality constraints of the facility and wastewater discharge See Section 3 4 (i) A narrative description of your system that has been designed to Not applicable reduce your intake flow to a level commensurate with that which can be attained by a closed -cycle recirculating cooling water system and any engineering calculations, including documentation demonstrating that your make-up and blowdown flows have been minimized, and (it) If the flow reduction requirement is met entirely, or in part, by Not applicable reusing or recycling water withdrawn for cooling purposes in subsequent industrial processes, you must provide documentation that the amount of cooling water that is not reused or recycled has been minimized (2) Velocity information You must submit the following information The Project is subject to § 125 84(c)(1) to the Director to demonstrate that you are complying with the requirement to meet a maximum through -screen design intake velocity of no more than 0 5 fps at each cooling water intake structure as required in §125 84(b)(2) and (c)(1) (i) A narrative description of the design, structure, equipment, and The facility will achieve a design through -slot velocity operation used to meet the velocity requirement, and of less than 0 5 fps using appropriately -sized wedgewire screens See Section 3 1 (u) Design calculations showing that the velocity requirement will be The screens are designed to be submerged at extreme low met gt minimum ambient source water surface elevations (based on water and they have been designed with sufficient area to best professional judgement using available hydrological data) and maintain the target velocity of less than 0 5 fps, even maximum head loss across the screens or other device when 15 percent of the slot area is obscured by debris See Section 3 1 (3) Source waterbody flow information You must submit to the The proposed intake would be located in a freshwater Director the following information to demonstrate that your cooling river, making subsection (3)(1) applicable water intake structure meets the flow requirements in 125 84 b 3 or (c)(2) (i) If your cooling water intake structure is located in a freshwater This section of the rule would limit the withdrawal to no river or stream, you must provide the annual mean flow and any more than 5 percent of the annual mean flow of the source supporting documentation and engineering calculations to show that waterbody The proposed maximum withdrawal is 4 194 your cooling water intake structure meets the flow requirements, MGD, or 6 49 cubic feet per second (cfs), which is 0 63 percent of the mean annual flow (1029 3 cfs) as estimated from 17 years of flow data at Wentworth, North Carolina See Section 3 1 � � N \PRANTE ENERGYILKC NPDES\R REPORTS\R REPORTS O42017 DOCX 1-7 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Table 2. Review of Proposed Intake Relative to the Requirements of 40 CFR 125.86(b) (n) If your cooling water intake structure is located in an estuary or Not applicable tidal river, you must provide the mean low water tidal excursion distance and any supporting documentation and engineering calculations to show that your cooling water intake structure facility meets the flow requirements, and (iii) If your cooling water intake structure is located in a lake or Not applicable reservoir, you must provide a narrative description of the water body thermal stratification, and any supporting documentation and engineering calculations to show that the natural thermal stratification and turnover pattern will not be disrupted by the total (4) Design and Construction Technology Plan To comply with § Project will follow compliance under Track I - § 125 84(c) 125 84(b)(4) and (5), or (c)(3) and (c)(4), you must submit to the Director the following information to a Design and Construction Technology Plan (i) Information to demonstrate whether or not you meet the criteria in As presented in Section 1 1, Rockingham County's § 125 84(b)(4) and (b)(5), or (c)(3) and (c)(4), proposed intake meets the criteria articulated at § 125 84(c)(3) and (c)(4) It believes that it has addressed the goals of the rule by utilizing closed -cycle cooling, wedgewire screens, and the 0 5 fps through -screen (u) Delineation of the hydraulic zone of influence for your cooling The hydraulic zone of influence is negligible for the water intake structure, intake structure given that the target through -slot velocity is less than 0 5 fps See Section 2 2 3 (iii) The owner or operator of a new facility required to install design Rockingham County has designed the intake to minimize and construction technologies and/or operational measures must impingement and entrainment through the design and develop a plan which explains the technologies and measures operational measures of the facility including intake selected, this plan shall be based on information collected for the location, use of closed -cycle cooling, wedgewire screens, Source Water Biological Baseline Characterization required by 40 and less than 0 5 fps through -screen velocity (A) A narrative description of the design and operation of the design A narrative description of the design and operation of the and construction technologies, including fish -handling and return facility and how it will minimize impingement is included systems, that you will use to maximize the survival of those species in Section 3 expected to be most susceptible to impingement Provide species - specific information that demonstrates the efficacy of the (B) A narrative description of the design and operation of the design A narrative description of the design and operation of the and construction technologies that you will use to minimize facility and how it will minimize entramment is also entrainment of those species expected to be the most susceptible to included in Section 3 entrainment Provide species -specific information that demonstrates the efficacy of the technology, and (C) Design calculations, drawings, and estimates to support the Drawings and calculations that illustrate these design descriptions provided in paragraphs (b)(4)(m)(A) and (B) of this features are included in Sections 3 4 and 3 5 section Source Rockingham County, 2017 A�C,� p N \PRANTE ENERGYU.KC NPDES\R REPORTS\R REPORTS O42017 DOCX 1-8 , Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 2.0 Source Water Physical Data [40 CFR 122.21(r)(2)I This section provides information on the physical characteristics of the source water body. The following text from the preamble of the final existing facilities rule provides context for this information requirement (preamble at 79 FR 48363). "This requirement is unchanged from the Phase I rule and the 2004 Phase II rule. The facility is required to submit data to characterize the facility and evaluate the type of waterbody potentially affected by the cooling water intake structure. The applicant is required to submit a narrative description and scaled drawings showing the physical configuration of all source waterbodies used by the facility, including areal dimensions, depths, salinity and temperature regimes, and other documentation that supports the determination of the waterbody type where each cooling water intake structure is located; identification and characterization of the source waterbody's hydrological and geomorphological features, and the methods used to conduct any physical studies to determine the intake's area of influence in the waterbody and the results of such studies; and locational maps. The Director uses this information to evaluate the appropriateness of any design or technologies proposed by the applicant." 2.1 Description of Source Water Body f 40 CFR 122.21(r)(2)(i)1 The proposed Project will be located in Rockingham County, at approximately N 36.334168, W 79.831705 (Figure 1), with intake and discharge structures located on the Dan River. The intake structure will be located at the river bank at approximately N 36.39019722, W 79.88805556, with a pump station located at the edge of the 100-year floodplain (Figure 2). The discharge point will be located at approximately N 36.410485, W 79.826908 (Figure 3). The Dan River flows within portions of both North Carolina and Virginia. The headwaters of the Dan River are located in Patrick County, VA, and flow into Stokes County, NC before meandering north through Rockingham County into portions of Southern Virginia, back into North Carolina in Caswell County, and eventually connects with the Roanoke River and Kerr Reservoir in southern Virginia. It is approximately 214 miles long, has a watershed of 3,300 A�C,� N \PRJ\NTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 2-1 If N TRANTE Enerjzy\LXC NPDES\R reportsTiguresTrevious Versions ofFiguresTigure 3 xlsx\2-4/14/2017 SEME 13RDGE (Sr- 2145) 5x, 1z 7, i rn').'AND —40,141-1a E�-C-' OF IVC1:US F 7�7 7" W 4 -30 R,'U- 42' ti 1 P F-'I,f-'E V.41, FW 1-17H47c.E W-4r'A'ALL ell- THIGV Lb-6S 2 %—WHWEL MrK 1, 90E5IJ'X-n ID C. ;Q 5'.-LE Is FFET LINE FM 55 A- 554 5 5-0 550 54E, 545 5 —42 542 538 538 iL 534 12' D I P MOR-7-E M-AN 5W :FKK-RyE HE.DWAL 534 533 5,12 04-E4 L.CvU. 526 DAN P,r-im 526 ...... ......... ......... 522 ..... ........... 522 303+00 303+50 304+00 304+50 3 + 00 3011+50 3D15+00 FIGURE 3 DISCHARGE PLAN AND PROFILE Source LKC, 2017 PRELIMINARY z ci U) 2 Ld U3 J 91,' °Exw z P-4 o It, 12' r, I P. D >'r, E FLL X KU < 24' 1HCL CLASS 7 FZIPPALU 1 DISCHARGE HEADYWALL PLAN C-0, i.0 11 2 FL I. W11 WALL FlrE \FcRil -ILL 24' THJ�V, OL,455 2 PI-Rer, (�2)DISCHARGE HEADYWALL SECTION \It4j 5'>LE- I/,' — I--0" r Environmental Consulting & Technology of North Carolina, PLLC N. TRJ\NTE Energy\L.KC NPDESA reports\Fjgures\Figure 2-033117.xlsx\2-3/31/2017 --- EDGE OF RIVER DAN RIVER .. RIVER ACCESS POINT STEPS AND LAPIDNG -- EDGE OF RIVER i PARCEL LINES -- — — — PROPOSED TRAIL -- _ Dc6TNG _ _ _ _.._.--- _ _._.. ■■ CONTOUR .i-- TYV PROPOSED �• •-' - ----�_-- --- �-----___ ADAACCESS ISLE __ OVERLOOK DECK 1 r r � POSTING 1D0 YEAR FLOOD .,� r rr i ` — _ -.. _ ... BUILDING \ \ STORAGE 5 DEWALKE t I I rr ANDADA DXTNG I ; i ( PARKING TRAIL 1 1 1 PROPOSED , TRAIL 1 PROPOSED PROPOSED 24' GRAVELRAWWATER ' I PARKING r l '{ LOT ' \\ \ r� � r r EMSTNG r CONTOUR TYP. DCISTNG . � TRAIL ,. y PROPOSED GRAVEL 1 DRIVEWAY ll PARCEL LNE � 1 Q � O RAW WATER INTAKE SITE PLAN QS SCALE: 1'- W FIGURE 2. RAW WATER INTAKE AND PUMP STATION SITE PLAN PRELIMINARY Source: LKC, 2017. PROPOSED NEW RAWWATER INTAKE ST RUCTURE WITH (2) 36"SCREENS AND SPACE FOR (1) ADDITICNAL SCREEN — 53$ 542 i — % 654 i •~�' '.� t00 YEAR FLOOD 562\ PROPOSED 570 NEWRAYWATER . PUMP STATION PARCEL F.F.E.: SSS.O' S74 LINES S7S1 PROPOSED GRAVEL / PARKNG PROPOSED GRAVEL ACCESS r DRIVEWAY r� r r r rr � - Environmental Consulting & Technology of G , North Carolina, PLLC Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance square miles, and comprises approximately one third of the Roanoke River Basin. Land use within the Dan River watershed in Rockingham County is predominately categorized for agricultural purposes, which includes open land areas that are currently unfarmed. Industrial and commercial uses combined account for less than one percent of the total county area (Rockingham County, 2010). The waters in the vicinity of the proposed CWIS and outfall are classified in North Carolina Water Quality Standards as Water Supply -IV (WS-IV). According to North Carolina Division of Environmental Quality (NCDEQ), WS-IV waters are "used as sources of water supply for drinking, culinary, or food processing purposes." WS-IV waters are also protected for Class C uses, which include protection for secondary recreation, fish consumption, and wildlife (15A NCAC 213 .0216). Surface waters in the vicinity of the CWIS are impaired for turbidity, in addition to a fish and shellfish consumption advisory for both mercury and coal ash in segments of the Dan River in Rockingham County (Table 3). A Total Maximum Daily Load (TMDL) for turbidity is in place for Dan River segment 22-(31.5), which limits permitted discharge to not exceed the state turbidity standard of 50 NTU. However, discharge from the proposed project will only have a projected maximum turbidity of 20 NTU. Mean annual flow in the Dan River near Wentworth (U.S. Geological Survey [USGS] gage 02071000), averaged 1029.30 cubic feet per second (cfs) for the last 17 years (2000 through January 2017). Water temperatures in the Dan River near Danville, Virginia (USGS gage 02075045), approximately 25 miles downstream of the proposed discharge, have an annual average (2007 to 2009) of 16.36 degrees Celsius (°C), with a low in January of 4.8 °C and a high in June of 27.6 'C. Water quality in the Dan River is monitored approximately 20 miles downstream of the proposed discharge, North East of Eden, North Carolina at USGS gage 02074218. The annual average pH is approximately 7.23. Dissolved oxygen is generally high, at an annual average of 9.88 milligrams per liter. A�,A� N \PRANTE ENERGY\LKC NPDES\R REPORTSIR REPORTS O42017 DOCX 2-4 A Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 3. Impairments and Appropriate Uses of Waters of Dan River within Vicinity of CWIS Water Body Dan River Stream Index 22-(31.5) Description From a point 0.7 mile upstream of Jacobs Creek to a point 0.8 mile downstream of Matrimony Creek Classification WS-IV and Class C standards (included in WS-IV classification) Impairments Fish consumption due to mercury and coal ash in fish tissue; Turbidity Source NCDEQ, 2017 2.2 Characterization of Source Water Body [40 CFR 122.21(r)(2)OM 2.2.1 Hydrology River flow data were obtained from the online hydrologic database NHDPIus and USGS gages at several stations along the Dan River: 02069000 at Pine Hall, NC, approximately 14 miles upstream of the proposed intake, 02071000 near Wentworth, NC, approximately 4 miles downstream of the proposed intake, and 02075045 near Danville, VA. The historical low flow of a river is defined as the lowest 7-day average flow that occurs in 10 years (7Q1o), which for the Dan River is 162 cubic feet per second (cfs), or 105 MGD (as provided by DEQ). 2.2.2 Geomorphology The proposed intake is located within the Piedmont physiographic province of North Carolina. This area typically consists of a 30-70 foot thick layer of clay overlying bedrock. The Triassic basin, a deep rift filled with sediment, stretches into portions of both Rockingham and Stokes counties. This basin is composed of fine textured and sparsely fractured sedimentary rocks, sandstone, mudstone, and sparse thin coal beds (Reid et al., 2011; Reid and Milici, 2008). Floodplains along the Dan River in Rockingham County contain highly porous deposits of unconsolidated sediments, like sand or gravel beds (Huffman, 1998). In the vicinity of the proposed intake and outfall, the Dan River exhibits this typical riverine morphology. �C� N \PRANTE ENERGY�LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 2-5 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance The Dan River is approximately 165 feet wide at the location of the proposed intake. Bathymetry surveys conducted in February 2017 at the proposed intake location indicated that the water depth was on average 7 feet (Figure 2). The proposed outfall is located 0.1 mile downstream of the confluence of Massy Creek and the Dan River and 3.2 miles upstream of confluence of Rock House Creek and the Dan River. The proposed outfall is approximately 40 ft northeast of the Settle Bridge Road bridge on State Route 2145 and approximately 22.5 miles upstream of the Virginia state border. Bathymetry surveys conducted at the location of the proposed outfall in February 2017 indicated that at the time of survey, the water depth was on average 4 feet (Figure 3). Under 7Q10 flow conditions, the average water depth is 2.3 ft and the maximum water depth is 3.0 ft. The river is approximately 130 feet wide -at the proposed outfall location. The Dan River segment in Rockingham County, NC is not actively dredged to maintain depth. The proposed construction of both the intake and outfall structures will not require dredging. 2.2.3 Determination of Area of Influence The area of influence (AOI) of a CWIS appears in three of the 40 CFR 122.21(r) sections of the Section 316(b) final rules for existing facilities: 40 CFR 122.2 1 (r)(2), Source Water Physical Data, "(ii). Identification and characterization of the source waterbody's hydrological and geomorphological features, as well as the methods you used to conduct any physical studies to determine your intake's area of influence within the waterbody and the results of such studies;" 40 CFR 122.2 1 (r)(4), Source Water Baseline Biological Characterization Data, states, "If you supplement... this section with data collected using field studies ... The study area should include, at a minimum, the area of influence of the cooling water intake structure." 40 CFR 122.2 1 (r)(1 1), Benefits Valuation Study (in the final existing facilities rule), states, "The study would also include discussion of recent mitigation efforts already completed and how these have affected fish abundance and A�� N\PRANTEENERGY\LKCNPDES\RREPORTS\RREPORTS O42017DOCX 2-6 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance ecosystem viability in the intake structure's area of influence." The Section 316(b) Phase I rule for new facilities states: "The area of influence is the portion of water subject to the forces of the intake structure such that a particle within the area is likely to be pulled into the intake structure." While this definition does not provide a clear means of estimating the AOI (e g., threshold velocity), it is common understanding that the AOI is that area of the source water body directly affected by the CWIS. Relative to impingeable organisms, generally juvenile and adult fish and shellfish, the concept is somewhat more concrete It could be assumed that it is the point at which the organism is no longer capable of overcoming the forces of water withdrawal and impinges upon an intake screen (Electric Power Research Institute [EPRI], 2007). This would be highly dependent on the swimming capabilities of the species and its life stage, size, and general health conditions, a point noted by EPRI in previous research on the relationship between intake approach velocity and the occurrence of impingement (EPRI, 2000). EPA considers a 0 5-foot-per-second (fps) through -screen velocity to be a de minimis value for the probability of impingement, which means a fish can swim freely in a flow at this velocity and avoid impingement (in fact, the studies showed a 1.0-fps threshold was protective, but it was halved as a safety factor). This is the basis for the 0.5 fps design criteria in the Phase I rule, and is a compliance option for impingement mortality BTA in the 316(b) final rule for existing facilities. For the latter, EPA indicates there is no need for any type of impingement protection, including impingement mortality studies, if the maximum design or actual maximum through -screen velocity of the CWIS is 0.5 fps or less (40 CFR 125 94[c][2] and [3]). Under these conditions, it is considered the facility has met the performance standards for impingement mortality. Therefore, the 0.5-fps contour for velocities induced by the CWIS delineates the CWIS's AOI for impingement. Two 30" diameter screens, with a blank flange for a third screen, in the proposed design of the intake structure will have a maximum design through -screen velocity of less than 0.5 fps; thus, the AOI for impingement at the intake, as defined by a threshold -induced velocity of 0.5 fps, is not exceeded in the waterbody. A �C, N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 2-7 , Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance A quantitative estimate of the area in which a "particle is likely to be drawn into the intake" is more difficult. Given the intake capacity is a small fraction of the mean annual discharge of the Dan River (i.e. 0.63%), most of the river's flow in the mainstem can be reasonably assumed to be "unlikely" to be drawn into the intake. 2.3 Locational Maps [40 CFR 122.21(r)(iii)] Figures 1, 2, and 3 present overall site plans identifying proposed MIS and outfall locations and configurations. p 0� N \PRANTE ENERGI\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 2-O 1 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance 3.0 Cooling Water Intake Structure Data [40 CFR 122.21(r)(3)] This section includes information on the CWIS that is used to determine the potential for impingement and entrainment at the facility, including a description of the structures and their location in the water body, as well as daily and seasonal operations and intake flows The following text from the preamble of the final existing facilities rule (79 FR 48363) provides context for this information requirement. "This requirement is unchanged from the Phase I rule and the 2004 Phase II rule. This data is used to characterize the cooling water intake structure and evaluate the potential for impingement and entrainment of aquatic organisms. Information on the design of the intake structure and its location in the water column allows evaluation of which species and life stages might be subject to impingement and entrainment. A diagram of the facility's water balance is used to identify the proportion of intake water used for cooling, make-up, and process water, as well as any cooling water supplied by alternate sources, such as reuse of another facility's effluent. The water balance diagram also provides a picture of the total flow in and out of the facility, and is used to evaluate gray water, wastewater, and other reuses in the facility. The applicant is required to submit a narrative description of the configuration of each of cooling water intake structure and where it is in the waterbody and in the water column; latitude and longitude in degrees, minutes, and seconds for each cooling water intake structure; a narrative description of the operation of each of cooling water intake structure, including design intake flows, daily hours of operation, number of days of the year in operation and seasonal changes, if applicable; a flow distribution and water balance diagram that includes all sources of water to the facility, recirculating flows, and discharges; and engineering drawings of the cooling water intake structure." 3.1 Narrative Description of CWIS [40 CFR 122.21(r)(3)(i)1 The Rockingham County Project's proposed cooling system is designed as a closed -cycle recirculating cooling system, where the cooling water is recycled and reused in the steam turbine condensers. The Project will employ one combustion turbine with supplementary � i N \PRANTE ENERGY\LKC NPDES\R REPORTSIR REPORTS O42017 DOCX 3-1 1 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance duct firing. The exhaust heat from the combustion turbine and the supplemental duct firing will be captured and converted to steam in a HRSG before passing through a steam turbine to generate additional power. The majority of the design intake water will be used for cooling. The operation of the Project will require an average daily withdrawal of approximately 2.766 MGD of water with a maximum daily withdrawal of approximately 4.194 MGD. The Project will have a single river CWIS to serve the generating units, located on the Dan River near Planters Road east of Madison, North Carolina (Figure 1). The Project intake will be located at approximately, N 36.390197, W-79.888086. The proposed intake is located on a 3.45-acre tract currently owned by Rockingham County, located along Planters Road, north of NC Highway 704 (Figure 2). Rockingham County is proposing to construct the intake structure on the bank of the Dan River. The Dan River in the area of the intake is a large, slow -flowing river, approximately 165 feet wide with an average depth of approximately 7 feet. The substrate is variable consisting of mainly of sand and gravel with cobble, boulder, bedrock, silt and clay. The concrete structure will be rectangular in plan view with the long dimension parallel to the flow direction. Plan view dimensions of the structure will be approximately 40 feet long by 15 feet wide. The structure will straddle the normal water elevation, with a portion of the structure protruding into the stream flow. On the river side of the structure will be concrete deflector walls, angled approximately 45 degrees in the downstream direction to prevent accumulation of large debris. The elevation of the structure is designed to allow the desired flow to enter the structure at the lowest expected water elevation, and the depth of the structure is determined by the required submergence over the intake screens. When water passes through the screens it will enter a pipe that goes through the wall, joins together in a manifold, and leads to the pump station structure (Figure 3). The CWIS will have two wedgewire intake screens, with a blank flange for a third screen. The screens will be stainless steel with a metallic coating system to prevent vegetative growth on the screens. The screens are designed for a maximum through -screen velocity of 0.5 fps at � r N \PRI\NTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 3-2 N \PRANPE Energy\L.KC NPDESUt reportsTiguresTigure 5 xlsx\2-3/31/2017 Dimensions Depth 30 in Length 44 in Flow Demand 4.5 MGD (6 97 fps) Max Design 2 76 MGD (4.28 fps) Avg Daily Screen Surface Area 4146.90 in 28 80 ft2 Screen Open Area 16.74 ft2 Average Slot Velocity 0.42 fps Max Design Flow 0.26 fps Avg Daily Flow Maximum Slot Velocity (15% blockage) 0.48 fps Max Design Flow 0.30 fps Avg Daily Flow 2 FIGURE 4. PROPOSED COOLING WATER INTAKE SCREEN DESIGN Source LKC, 2017 0 MD, - Environmental Consulting & Technology of G , North Carolina, PLLC Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance the peak flow rate with 15% allowance for blockage. This maximum velocity will be accomplished through the screen design using the specifications illustrated in Figure 5. The screens will be 30 inches in diameter and will employ a 0.125-inch slot size. Using 0.09-inch wire, each screen will have an open area of 58.14% or 16.74 ftz. For design calculations, a maximum withdrawal rate of 4.5 MGD was used. As designed, the maximum through -screen velocity will be 0.42 fps. The maximum through -screen velocity accounting for 15% blockage due to potential biofouling and/or debris will be 0.48 fps as evidenced in the calculations presented below. As designed, the average daily through -screen velocity will be 0.26 fps. The through -screen velocity at average flows accounting for 15% blockage will be 0.30 fps and is evidenced by the calculations below. An air burst system will be used to ensure that the screen open area can be maintained below 15% blockage by periodically dislodging accumulated silt and debris. Calculation of Through -Screen Velocity Screen Dimensions Diameter = 30 inches Length = 44 inches Wire Size = 0.09 inches Slot Size = 0.125 inches % Open Area = 58.14% Flow Demand Maximum Flow Design Demand = 4.5 MGD 4.5 MGD to ft3/s = 6.97 ft3/s Daily Average Flow Demand = 2.76 MGD 2.76 MGD to ft3/s = 4.28 ft3/s Screen Surface Area 7c x D x Screen Length = 7c x (30") x (44") = 4146.90 in in to ft2 = 28.80 ft2 Screen Open Area Screen surface area x % open area = (28.80 ft2) x (58.14%) =16.74 ft2 � s N \PR>\NTE ENERWLKC NPDES\R REPORTS\R REPORTS O42017 DOCX 3-4 FIGURE 5. PRELIMINARY WATER BALANCE DIAGRAM Description Stream No Winter Ptred Averge An nua I Summer Pired Instant., Ambient Condition ('DB / WS) 25/23 59 /53 92,176 20., Duct Burner ,/ Evap cooler on / off on / off on, on 0 gprn mgd 9prn mgd 9pm mgd 9p Raw Water at Battery Limit to Clarifier 1 1,432.1 2.063 1,920.5 2 766 2,4014 8.461 21912 Clarifier -Solids 4sposa I retained water 2 14 0.(>02 1-9 0.003 7.4 0.003 2 Water to Raw Water/Firewater Talc 3 21,8 0,032 52-6 0,076 84,1 0-121 95, Fire Water 5t5tern 4 - - - - - - - Service Water System 5 21.8 0,031 526 0.076 84.1 0.121 95, CT make-up 6 1,409,1 2,029 1,866.0 2.687 2,317,0 3.316 2,814, CT Drift loss 7 06 0001 0.6 0001 0.6 0.001 0 CT Evap ration loss 8 1r245 0 1.793 1,650.0 2376 2r050.0 2-952 2,170 CT Blowdqwn 9 206.9 0 298 274.4 0395 3410 0.491 772 Not used 10 Quench water to H RSG Blowdown Plant Wash Down 11 12 16.8 5.0 0,024 0,007 16.9 5.0 0,024 O.W7 16.9 5.0 1024 0.007 16, 5, Contaminated Drains to OWS n 5,0 0.007 5.0 0007 5,0 OM7 S Make-up to CTG Evap Cooler 14 - - 80.7 0044 622 (1-090 74 CTG inlet evaporative cooler evaporation 15 15.4 010212 31.1 0.045 37 CTG inlet evaparatvie cooler blow down 16 - - 15.4 0,022 31,1 0.045 37 Potable waterat Batted Limit/back-flow Potable water/Sanitary eventer 17 18 45,3 2,0- 0.06-5 0.003 45.5 2.0 ()5 0.055 0.003 455 2,0 M65 0.003 44. 2. Water to RO/Mixed Bed units 19 43.3 0,062 43-5 0,061 43,5 0.063 42, Recovered outer from PLO/Mixed 8,ed unit 20 87 0012 8-7 0013 8.7 0.011 9 DM Water to StoraV tank 21 346 0,050 34.8 0050 348 0-050 34 Make-up to Steam cycle 22 34.6 0050 34-8 0,050 34.8 0.050 34 misc losses 23 510 0,007 5,0 0,007 510 0.007 5 Steam samPlin losses Steam cycle Blowdown 24 25 6,0 216 0.009 0.034 6.0 218 0,009 0,034 a 6.0 23,8 0.009 0.034 6 23 Stea m vent losses 26 57 0.1)u 5.71 0,008 5.7 0.008 S Water from flash tank 27 34.7 0050 34-9 0050 349 0.050 33 Sanitary waste to an site leach field 28 2�0 0.003 2.0 01003 2.0 0.003 7 [Waste Water to off site lift station 29 217,91 0,314 285.4 0,411 L 352.9 ... ... . 9.507] 733 FIGURE 6 PRELIMINARY WATER BALANCE - WATER USE SCENARIOS Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Average Slot Velocity Max Flow Design Demand/screen open area = (6.97 ft3/s)/ (16 74 ftz) = 0.42 fps Avg Daily Demand/screen open area = (4.28 ft3/s)/ (16.74 ftz) = 0.26 fps Maximum Slot Velocity (Assume 15% blockage) Average Max Design Slot Velocity x 15% = 0.42 fps x (1.15) = 0 48 fps Daily Average Slot Velocity x 15% = 0.26 fps x (1.15) = 0 30 fps The two screens described above will include sufficient total open area to pass the 4.5 MGD flowrate with a through -screen velocity below the 316(b) Phase I rule's 0.5 fps velocity limit while allowing for 15% blockage. Rockingham County will implement multiple safeguards to minimize the likelihood of impingement and entrainment due to its CWIS. The measures are consistent with the intake guidance developed by the EPA's Phase I rule requirements (see Table 1). The following is a summary of the measures adopted in the design and placement of the cooling water intake structure to minimize potential effects of impingement and entrainment The proposed facility will use closed -cycle recirculating cooling consistent with Track I of the 316(b) rule Such a system reduces intake flow by more than 95 percent relative to a similar once -through -cooled facility. Given that rates of both impingement and entrainment are generally assumed to be proportional to the rate of water use, both will be reduced by a commensurate amount. The system will use submerged wedgewire screens to passively exclude debris and aquatic organisms. Such systems have been demonstrated to minimize impingement and entrainment without excessive handling that may occur with more traditional traveling water screens. The intake will employ wedgewire screens that have been shown to reduce impingement and entrainment even in organisms smaller than the slot size by inducing an avoidance response in the organism (Coutant, 2015; Zeitoun et al, 1981). The system will be designed to have a maximum through -slot velocity of 0.48 fps even when partially clogged by debris (allowance for 15% blockage). This is AM9 � N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 3-7 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance well below the commonly assumed escape speed that allows fish to avoid impingement and should essentially eliminate impingement of juvenile and adult fish. The slot size will be 0 125 inches (3.175 mm). The intake has been located on the bank of the river to minimize impacts to the bed of the river and associated habitats, migratory species and those that use the main stem of the river, and recreational activities in the river 3.2 Latitude and Longitude of CWIS [40 CFR 122.21(r)(3)(ii)] The coordinates for the intake are - Latitude. 36.390197 Longitude:-79.888086 3.3 Description of CWIS Operation [40 CFR 122.21(r)(3)(iii)] The Project and its cooling water system are intended for a year-round, 24-hours-per-day operation, with the exception of down time due to outages. When the facility is producing electricity, the intake structure will generally be fully operational. The cooling water demand will change based on level of generation and weather conditions. Some amount of cooling water storage is present in the cooling tower basins (e.g., sufficient for a small number of hours of operation), and pumps will be dispatched based on the need to replenish cooling tower water levels. The Project's nominal output is 488 megawatts 3.4 Intake Flow [40 CFR 122.21(r)(3)&)] Figures 6 and 7 present water balance diagrams for the proposed operation assuming seven cycles of concentration. Figure 6 presents the water balance diagram, while Figure 7 presents balance flows through the system for four conditions. The instantaneous peak can be considered the maximum demand condition. The Project's proposed maximum withdrawal is � � N \PR.A= ENERGYTKC NPDES\R REPORTS\R REPORTS O42017 DOCX 3-8 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance 4.194 MGD (6.49 cfs). Both HRSG blowdown and reject from the first pass of the reverse osmosis system will be recycled as additional cooling tower makeup The proposed maximum consumptive use is approximately 3.134 MGD and will result in a return of 1.06 MGD. Cooling tower makeup water will be the dominant water use at the facility, averaging 2.687 MGD, while maximum cooling tower makeup water rates will be 4.052 MGD. Smaller streams include RO/demineralization (0.061 MGD to 0.063 MGD) and plant service water needs (0.076 MGD average; 0.137 MGD max). Also included in the water balance diagrams is the proposed usage of potable water from Rockingham County (averaging 0.065 MGD). A�,� N \PRS\NTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 3-9 G I Rockingham Rockingham County Dan River Intake Submittals Related to Section .316(b) Compliance 3.5 Engineering Drawings of CWIS [40 CFR 122.21(r)(3)(v)1 Figures 2 and 4 present the engineering drawings of the CWIS. A�C� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 3 -1 O 1 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 4.0 Source Water Baseline Biological Characterization Data [40 CFR 122.21(r)(4)] This section addresses each of the elements of 40 CFR 122.21(r)(4). The following subsections are numbered and titled consistent with the sections of 40 CFR 122 21(r)(4). Please note that the discussion of threatened and endangered (T&E) species as required by 40 CFR 122.21(r)(6) has been included and modified to also address the requirements to list both state and federally listed species and designated critical habitat per 40 CFR 125 95(f). 4.1 List of Unavailablek-BioCogical Data [40 CFR )l - 122.21(r)(4)(i The Dan River in the vicinity of the proposed intake is well studied and therefore data needed to prepare the elements of the requirements of 40 CFR 122.21(r)(4) were available in the literature 4.2 List of Species and Relative Abundance in the Vicinity of MIS F40 CFR 122.21(r)(4)1 A number of studies were reviewed when compiling the list of species and relative abundance in the vicinity of the CWIS• Rhode et al studies — Longitudinal Study and Annotated List of Fishes from the Dan River North Carolina Water Resources Commission (NCWRC) data Duke Energy data Based on these studies, 75 species in 10 families are known to occur in the Dan River near the N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-1 A Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance intake. Data from the Rhode studies and Duke Energy were used to estimate the relative abundance of the species (Table 4). The most commonly collected species were redbreast sunfish, golden redhorse, white shiner, and satinfin shiner. 4.2.1 Rhode et at. Studies Rhode et al. published a paper on the Longitudinal Succession of Fishes in the Dan River in 2001 and an updated Annotated List of the Fishes Known from the Dan River in 2003. These papers use available fish collection data from the Dan River segmented by physiographic province to list species and relative abundance in each area. The CWIS is located in the Fault Basin and Table 4 lists species and relative abundance for this area. Included in this list are 58 species from 138 sampling events. Sampling events consisted of collections made with seines, backpack electroshockers, and /or boat electroshockers. 4.2.2 NC Wildlife Resources Commission NCWRC provided data collected in the Dan River in Rockingham County from November 1984 to June 2016. Surveys were conducted for a variety of reasons and consisted of electrofishing with backpack or boat and/or seine samples. These studies were typically used to determine presence/absence for species and are not standardized for collection efforts. Table 4 includes the species collected in the Dan River in Rockingham County by NCWRC 4.2.3 Duke Energy Recent data from a study conducted by Duke Energy were also provided by NCWRC. These data were collected from three sampling locations in the Dan River near Eden, NC (approximately 14 to 20 miles downstream from the CWIS). Four sampling events were conducted during 2016. The majority of the sampling was conducted by boat electrofishing with some net sampling also. Table 4 also includes results from these sampling efforts. These comparisons indicate that the earlier studies remain representative of current conditions in the river, noting that a few dominants move slightly in overall ranking. The presence of several additional sub -dominants in the 2016 Duke Energy data may be attributable to the addition of sampling using nets, while the inclusion of rarer species in the Rhode et al. studies may be attributable to the larger sampling effort. A�C� N \PRRNTE ENERGI'\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-2 Rockingham C Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 4. Summary of Dan River Fish Survey Results with Relative Abundance Scientific Name Common Name Duke Energy Rhode et al. Studies wildlife Resources Commission Lepomas auratus Redbreast sunfish 1945 2357 X Moxostoma erythrurum Golden redhorse 1845 1051 X Luxalus albeolus White shiner 1775 6.93 X Cypranella analostana Satinfin shiner 3 12 17.16 X Nocomas raneya Bull chub 3.40 5.82 X Notropas amoenus Comely shiner 759 1 34 X Lepomas macrocharus Bluegill 252 64 X Lythrurus ardens Blueside shiner 3 12 457 X Moxostoma pappillosum Slender redhorse 560 1.79 X Notropas hudsonaus Spottail shiner 258 2.76 X Macropterus salmoades Largemouth bass 264 256 X Ameaurus brunneus Snail bullhead 0.50 455 X Notropas chahtacus Redlip shiner 221 X Nocomas leptocephalus Bluehead chub 1.42 217 X Lepomas macrolophus Redear sunfish 1 32 0.97 X lctalurus punctatus Channel catfish 1 13 1 Moxostoma collapsum Notchlip redhorse 082 085 Pomoxas nagromaculatus Black crappie 0.94 0.62 X Catostomus commersoma White sucker 1 13 038 X Ameaurus platycephalus Flat bullhead 0.60 087 X Hypentehum nagracans Northern hog sucker 072 068 X Luxalus cerasanus Crescent shiner 067 X Moxostoma cervanum Blacktip jumprock 0.66 Lepomas cyanellus Green sunfish 0.09 1.14 X Cypranus carpao Common carp 041 068 X Macropterus dolomaeu Smallmouth bass 082 012 X Dorosoma cepedaanum Gizzard shad 035 055 X Etheostoma podostemone Riverweed darter 044 X Carplodes cypranus Quillback 057 0.22 X Notemagonus crysoleucas Golden shiner 0 19 0.55 X Noturus ansagnas Margined madtom 0.44 026 X Percana roanoka Roanoke darter 0.03 056 X Notropas procne Swallowtail shiner 0.22 036 X Lepomas gabbosus Pumpkinseed 022 027 X Amblophtes cavafrons Roanoke bass 038 004 X Cypranella lutrensas Red shiner 019 0.09 X Ameaurus nebulosus Brown bullhead 009 016 X Etheostoma flabellare Fantail darter 0.12 X Scartomyzon cervanus Black jumprock 012 X A�,� N \PRANTE ENERGY�LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-3 G Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Table 4. Summary of Dan River Fish Survey Results with Relative Abundance Scientific Name Common Name Duke Energy Rhode et al. Studies Wildlife Resources Commission Etheostoma olmsteda Tessellated darter 0.09 Percana nevasense Chamback darter 009 X Pomoxis annularas White crappie 003 014 X Hypentehum roanokense Roanoke hog sucker 0 13 004 X Ameaurus catus White catfish 003 0 13 X Nocomas macropogon River chub 006 X Lepomas gulosus Warmouth 006 006 Ambloplates rupestris Rock bass 005 X Scartomyzon araommus Bigeyejumprock 003 0.06 Moxostoma macrolepadotum Shorthead redhorse 0.03 004 X Perca flavescens Yellow perch 003 Percana crassa Piedmont darter 003 Carassaus auratus Goldfish 003 Ameaurus melas Black bullhead 0.02 X Ameaurus natahs Yellow bullhead 002 X Campostoma anomalum Central stoneroller 002 X Esox ameracanus Redfin pickerel 002 X Etheostoma nagrum Johnny darter 002 Gambusaa holbrooka Eastern mosquitofish 002 X Phoxanus areas Eurasian minnow 002 Salmo trutta Brown trout 002 Etheostoma vatreum Glassy darter 001 Lepasosteus osseus Longnose gar 001 Semotalus atromaculatus Creek chub 001 X Ameaurus sp Catfishes X Etheostoma sp Darters X Ictalurus punctatus Channel catfish X Ictalurus sp Catfish X Lepomas sp Sunfish X Macropterus sp Sunfishes X Moxostoma anasurum Silver redhorse X Moxostoma araommum Bigeye jumprock X Moxostoma sp Suckers X Nocomas sp Chubs X Percma peltata Shield darter X Percana rex Roanoke logperch X Sources Duke Energy 2016 NCWRC, 2016 Rhode et al, 2003 �W A� N \PRANTE ENERGY�LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-4 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 4.3 Identification of Species and Life Stages Susceptible to I and E 40 CFR 122.21(r)(4)(il Table 5 outlines the potential for each of the twenty most common fish species found in the Dan River to be present around the intake as well as the potential for impingement or entrainment for each species. Table 6 includes habitat preferences and spawning information and was used to compare habitat preferences for the common species in the Dan River with the habitat near the intake. The Dan River in the area of the intake is a large, slow -flowing river, approximately 165 feet wide with an average depth of 7 feet. The substrate is variable consisting of mainly of sand and gravel with cobble, boulder, bedrock, silt and clay. Impingement and entrainment at the facility will be greatly reduced by the design factors of the facility and the MIS itself. The facility will operate as a closed -cycle system using cooling towers to reduce the water supply needs of the facility. Such a system reduces intake flow by more than 95 percent relative to a similar once -through -cooled facility. Given that rates of both impingement and entrainment are generally assumed to be proportional to the rate of water use, both will be reduced by a commensurate amount. In addition, the intake flows are a very small proportion of the river's discharge. The low proportion of intake flow relative to the river discharge also indicates that any entrainment losses from the system will be extremely small relative to the extant population The intake will employ wedgewire screens that have been shown to reduce impingement and entrainment even in organisms smaller than the slot size by inducing an avoidance response in the organism (Coutant, 2015; Zeitoun et al., 1981) The potential for impingement of any of the species is greatly limited by the design through -screen velocity of the plant being less than 0.5 fps which is the basis for the velocity threshold in the Phase I rule. In its final rule - making for existing facilities, EPA adopted this intake velocity threshold as a pre -approved technology per 40 CFR 125.94(c) (2) and (3). As noted previously, the use of wedgewire screens in combination with the low intake velocity would also be expected to reduce the rates of entrainment substantially. A�� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-5 G Coun Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 5. Potential for Impingement and Entrainment of Fish Species Located within the Vicinity of the Proposed MIS Potential for Potential for Common Name Scientific Name Potential to Occur Near the Intake Entramment of Early Impingement Early Life Stages Juveniles/Adults Life Stages of Adults and Juveniles SUCKERS CATOSTOMIDAE White sucker Catostomus commersonu Notchlip Moxostoma redhorse collapsum Golden redhorse Moxostoma erythrurum Slender redhorse Moxostoma pappillosum CENTRARCMDAE Redbreast Lepomrs auraus sunfish Bluegill Lepomrs macrochirus Redear sunfish Lepomrs microlophus Largemouth bass Micropterus salmoides Black crappie Pomoxts nigromaculatus CYPRIMDAE Satinfin shiner Cyprinella analostana White shiner Luxilus albeolus Blueside shiner Lythrurus ardens Unlikely, spawns in swift water Likely Slight potential, spawns in runs Likely and riffles Slight potential, spawns in runs Likely and riffles Unlikely, migrates upstream to Likely spawn Some potential Likely Some potential Some potential Some potential Likely Some potential Some potential, little is known about spawning habits Unlikely, spawns in faster currents Unlikely, eggs are adhesive, spawns in swift water Slight potential Slight potential Unlikely Slight potential Likely Slight potential Likely Unlikely, male guards nest and hatchlmgs Likely Unlikely, male guards nest and hatchlmgs Likely Unlikely, male guards nest and hatchlmgs Some potential Likely Likely Unlikely, eggs are adhesive Slight potential Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely Unlikely �'� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-6 L Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Table 5. Potential for Impingement and Entrainment of Fish Species Located within the Vicinity of the Proposed CWIS Common Name Scientific Name Potential to Occur Near the Intake Early Life Stages Juveniles/Adults Potential for Entrainment of Early Life Stages Potential for Impingement of Adults and Juveniles Bluehead chub Nocomts Some potential Some potential Slight potential Unlikely leptocephalus Bull chub Nocomts raneyt Some potential Some potential Slight potential Unlikely Comely shiner Notropts amoenus Some potential Likely Slight potential Unlikely Redlip shiner Notropts chiliticus Some potential Likely Slight potential Unlikely Spottail shiner Notropts hudsonius Unlikely, migrates upstream to Likely Unlikely Unlikely spawn near mouths of creeks ICTALURIDAE Snail bullhead Ameturus brunneus Some potential, little is known Likely Slight potential Unlikely about spawning habits Flat bullhead Ameturus Some potential, likely similar to Likely Unlikely Unlikely platycephalus other bullheads, one or both parents guard the nest and hatchlings Channel catfish lctalurus punctatus Some potential Likely Unlikely, male guards Unlikely nest and hatchlings Sources NatureServe 2017 ECT 2017 � � q N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX ` -7 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 6. Seasonal and Daily Activities of Fish Species Located within the Vicinity of the Proposed CWIS Common Name Scientific Name Seasonal Activities/Spawning/Migration SUCKERS White sucker Notchlip redhorse Golden redhorse CATOSTOMIDAE Catostomus Spawn in spring in swift water or rapids, often in commersonn small, clear, cool creeks and small to medium rivers Sometimes spawn on lake shoals, beaches or river mouths with wave action Eggs sink and usually stick to and become lodged in gravel Can migrate dozens of kilometers between non - spawning and spawning habitat Moxostoma Spawns in groups in spring in runs and riffles with collapsum gravel and small cobble substrates Moxostoma Spawns in the spring in runs and riffles of small to erythrurum large rivers but may also travel to small tributaries Males congregate and defend territories before and during spawning Slender redhorse Moxostoma pappillosum SUNFISHES CENTRARCHIDAE Redbreast Lepomis auritus sunfish Probably spawns late spring and early summer Migrates upstream to spawn Spawns throughout warmer months in nest made by male in shallow water on bottom Often nests in colonies Male guard eggs and hatchlings Daily Activities/Migration/Habitat Occur in a wide variety of lake and stream habitats Formerly included with M umsut urn Typically found in rivers and larger streams, but also in medium sized streams and impoundments, usually over silt, sand, gravel, or rock substrates Found in creeks and small to large rivers with various substrates, usually in pools often with sand and silt Found in rocky runs and silty to firm -bottomed pools of small rivers, occasionally in impoundments Occur in deeper waters of warm quiet ponds, lakes, backwaters of small to medium rivers, reservoirs, and swamps Usually in clear water with abundant vegetation, stumps, logs, or other cover, with mud or sand substrate Occasionally in brackish water � � N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-8 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 6. Seasonal and Daily Activities of Fish Species Located within the Vicinity of the Proposed CWIS Common Name Scientific Name Seasonal Activities/Spawning/Migration Daily Activities/Migration/Habitat Bluegill Lepomis macrochirus Spawning occurs over an extended period in spring Occur in warm shallow lakes, reservoirs, ponds, and and summer Often spawn in colonies that may slow -flowing rivers and streams Often associated include dozens of crowded craterlike nests that are with rooted aquatic plants and silt, sand or gravel guarded by males Nest built in shallow water on substrate Rarely go deeper than 16 feet Large adults gravel, sand or mud substrate. seek more open water than smaller and feed through water column Redear sunfish Lepomzs mzcrolophus Largemouth bass Micropterus salmoides Black crappie CARPS AND MINNIOWS Satmfin shiner POmoxIS nigromaculatus �CYPRINIDAE Cyprinella w analostana Spawning generally occurs from late spring to early summer Shallow nests usually located in water less than 2 meters deep often occur in dense groups. Males guard the eggs and hatchlings Spawn in shallow cleared depressions (nests) made by males in sand, gravel, or debris -littered bottoms, often at depths of 1 to 2 meters but up to 7 meters. Spawn mainly in spring or early summer after water temperatures have become warm enough Males guard eggs and hatchlings until young disperse after a month Have small summer range or may wander wildly Young have strong schooling tendency Generally, in deeper water in winter than in summer Spawning occurs in spring and summer Nests constructed in shallow water usually less than 1 in deep, sometimes in proximity to each other Males guard eggs and hatchlings Spawn in late spring and summer Males guard nest territory. Eggs attached to branches, stumps, logs, cracks in rocks, in crevices under loose submerged bark, between exposed tree roots, or under flat rocks Found in a variety of habitats in ponds, lakes, reservoirs, swamps, streams, and small rivers, often in or near vegetation and over a mud or sand bottom. Inhabit warm, quiet waters with low turbidity, soft bottoms, and beds of aquatic plants Typical habitats include farm ponds, swamps, lakes, reservoirs, sloughs, creek pools, and river coves and backwaters Active throughout most of daylight hours and usually relatively inactive at night and in winter, feeding most intense near dawn and dusk to warmer months Usually found in vegetated areas of backwaters in streams and rivers, ponds, and reservoirs Usually associated with large beds of aquatic plants and sandy to mucky bottoms Travels in schools. Habitat includes rocky and sandy runs of creeks and small to medium rivers, usually near riffles Occasionally found in headwater and tidal portions of some large rivers �C� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-9 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 6. Seasonal and Daily Activities of Fish Species Located within the Vicinity of the Proposed CWIS Common Name Scientific Name Seasonal Activities/Spawning/Migration White shiner Blueside shiner Bluehead chub Bull chub Luxalus albeolus Lythrurus ardens Nocomas leptocephalus Nocomas raneya Comely shiner Notropas amoenus Redlip shiner Notropas chalatacus Spottail shiner Notropas hudsonaus ,BULLHEAD ICTALURIDAE CATFISHES Snail bullhead Ameaurus brunneus Little is known about reproduction of this species it is probably similar to L cornutus, which spawns over gravel beds Spawning occurs from late April to mid or late June in faster currents of riffles or pools. Uses nests of chubs or fallfish. Found in deeper pools in winter Spawn on gravel mound nests made by males from April to early July Male constructs mound nests with gravel and stone in May to June. Spawns throughout summer, especially in June Spawning has been observed in late May at water temperatures of 11-17 °C Spawns on nests of bluehead chub (large gravel mound with one or more pits) Spawns in spring or early summer May migrate up tributary streams to spawn Spawns in aggregations over areas of gravelly riffles near mouths of brooks or along sandy shoals of lakeshores Daily Activities/Migration/Habitat Found in clear to moderately turbid creeks to medium rivers with riffles and flowing pools and rubble or rubble and gravel substrates Found in pools, backwaters and runs of warm water large creeks and rivers Generally found in mid to higher depths over soft and hard bottoms. Inhabit swift current and pools with highly varied substrate Found in swift water and pools of small to medium rivers and creeks with gravelly to rocky sections Streams where this species is found are typically moderate gradient, warm water, and clear Schooling midwater fish found in various habitats, usually in runs and flowing pools of creeks and medium to large rivers Found in flowing pools of clear headwater creeks, and small rivers in the Piedmont and mountains Prefers areas with sand and gravel to rubble Occurs in large sluggish coastal rivers and brackish water to small clear rapidly flowing montane streams Little is known about reproduction of this species Found in rocky riffles, shoals, runs, and pools in data suggest that spawning occurs in late winter streams and rivers through summer. �C� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4- 1 O Rockingham Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance Table 6. Seasonal and Daily Activities of Fish Species Located within the Vicinity of the Proposed CWIS Common Name Scientific Name Seasonal Activities/Spawning/Migration Daily Activities/Migration/Habitat Flat bullhead Ameiurus Spawns in June to July Likely similar to other Adults found in slow moving waters of small to large platycephalus bullheads the one or both parents guard the nest rivers with muddy bottoms and detritus. Younger and hatchlings individuals tend to be found in smaller and clearer streams Also occurs in lakes, ponds, and impoundments Channel catfish lctalurus punctatus Sources NatureServe 2017 Spawns in later spring and summer in cavelike sites Young -of -year live full time in riffles Males guard and fan water over nest during incubation and stay with young after hatching N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-11 Occur in main channels of small to large rivers, from clear, rapidly flowing firm -bottoms streams to turbid, mud- bottomed streams Avoids upland stream Adults found in pools or under logjams during day and move to riffles at night Nocturnal Most active at night when water levels are rising Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance While the data from ambient sampling represent a reasonable survey of types of fish that would be potentially subject to impingement and entrainment at the CWIS, it is expected that actual impingement and entrainment rates at the facility will be very low due to the design of the intake. 4.4 Identification and Evaluation of Primary Growth Period F40 CFR (r)(4)(iyfl The primary growth period for most species follows spawning and subsequent hatching. Shortly after hatching, larvae are at their greatest abundance and have rapid growth rates The majority of the species found in the Dan River spawn in the spring and summer and therefore have their primary growth period in the summer and early fall when the water is relatively warm and food is abundant. Table 6 summarizes the seasonal activities and spawning periods for each species of common fish found in the Dan River expected to be within the vicinity of the CWIS. 4.4.1 Reproduction The majority of species found in the Dan River spawn in the spring and summer months, with a few species beginning spawning in late winter and one species beginning spawning in the fall. Table 6 includes spawning habits for the fish species identified as common in the Dan River. 4.4.2 Larval Recruitment and Period of Peak Abundance The larval recruitment period follows spawning by a few days to a week or more, depending on incubation times for each species and ambient water temperature. The period of peak abundance generally occurs around the time of hatching as the new larval recruits greatly add to the abundance of each species. The spawning period for most species common in this area is in the spring and summer months, leading to peak abundance in eggs around this time and larvae shortly after. The exception to this is redfin pickerel, snail bullhead and yellow perch, which may also spawn in late winter; and brown trout which spawns in fall or early winter. Peak abundance of juvenile fish will lag the spawn by a few months. Multiple -spawning fish J�C,A� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4- 12 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance show additional peaks through the summer and fall in relation to their multiple spawning times. 4.5 Data Representative of Seasonal and Daily Activities of Organisms in the Vicinity of CWIS [40 CFR 122.21(r)(4)(v)] Table 6 summarizes the data representative of seasonal and daily activities for the dominant species observed in the Dan River. Seasonal activities consist of many species migrating upstream to tributaries in the spring and summer for spawning. Daily activities include movements for feeding and protection. Many species either move up and down in the water column or into deeper or shallower waters in response to light, food availability, or temperature. 4.6 Identification of Threatened. Endangered, and Other Protected Species Susceptible to I and E at CWIS F40 CFR 122.21(r)(4)(ivf] The 316(b) rule modified the existing requirements of 40 CFR 122.21(r)(4)(vi) by replacing the former requirement to list state- and federally listed protected species with those listed by the federal government (40 CFR 125.95[f]) Given the likely interest in state -listed species, this section will address both state- and federally listed species. Federally listed T&E species and critical habitat are protected by the Endangered Species Act of 1973 (ESA) and subsequent amendments. The ESA is administered by two federal agencies, the U.S. Fish and Wildlife Service (USFWS) and NOAA Fisheries. NOAA Fisheries oversees marine species, and USFWS has responsibility over freshwater fish and all other terrestrial and aquatic species. Federally listed threatened and endangered species are protected by the ESA; special concern species indicate a species that is in danger of becoming threatened but is not officially protected by the ESA. USFWS recommends use of their Information Planning and Conservation (IPaC) tool for determining which species may be affected by a project. A�C,"W N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-13 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance State listed wildlife species are protected by the North Carolina Wildlife Resources Commission (NCWRC) and North Carolina Natural Heritage Program (NCNHP), under the State Endangered Species Act (Chapter 113 331 through 337, Article 25, North Carolina General Statutes [G.S.]). State listed plant species are protected by the North Carolina Department of Agriculture Plant Conservation Program and NCNHP under the Plant Protection and Conservation Act of 1979 (G.S. 19B 106 202) State -listed endangered, threatened, and special concern species are protected by state law; significantly rare designations indicate a species that is rare and in need of monitoring. NCNHP database provides lists of rare plant and animal species by USGS quadrangle. Information regarding the potential presence of federally listed species or critical habitat was obtained from online databases including USFWS's IPaC website, NOAA Fisheries website, and NCNHP. Table 7 includes state and federally listed species with the potential to be found in the vicinity of the proposed CWIS, as well as habitat preferences for each listed species. There is no designated critical habitat near the Project intake. Table 8 includes range and reproductive habits for listed aquatic species. Note that while the table includes special concern and rare species, only federally listed threatened or endangered species are protected by the ESA and only state listed threatened, endangered, or special concern species are protected by the state law. Cutlip minnow and James spineymussel were not collected in the Dan River in any of the available studies. Roanoke bass, quillback, riverweed darter, bigeye!umprock, and Roanoke logperch are known to occur in the Dan River. The 0.5 fps intake velocity makes it unlikely that any species would be impacted by impingement Roanoke bass, riverweed darter, and Roanoke logperch have adhesive eggs and cutlip minnow eggs are buried in nest mounds. Quillback migrate upstream to spawn Therefore, it is unlikely that eggs of these species would be entrained Little is known about the spawning habits of bigeye jumprock. Habitat preferences and spawning habits combined with the design of the intake make it unlikely that impacts to any listed species would occur as a result of the intake. A�� N \PRANfE ENERGY\L.KC NPDESUL REPORTSUL REPORTS O42017 DOCX 4-14 A I Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance It is highly unlikely that adult mussels would be impinged because they are typically only found buried in the substrate. It is also unlikely that glochidia (mussel larvae) would be impinged or entrained since they have a very short plankton phase typically attach to host within a few days, and many are released in conglutinates (aggregates of glochidia). It is unlikely that host fish with glochidia would be impinged because the plant was designed to reduce impingement by employing a less than 0.5 fps approach velocity. N TRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-1 5 CC7 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Table 7. List of State and Federally Protected Species Potentially Occurring In the Vicinity of the Proposed CWIS Scientific Common State Federal Habitat Description Status Status FISH Amblophtes cav fronsRoanoke Bass SR FSC Occupies Valley and Ridge, Piedmont, and upper Coastal Plain provinces Stocked in upper and lower James and middle New drainages in Virginia and North Carolina impoundments and streams, but stocking did not establish extant populations Typically occurs in rocky and sandy pools of creeks and small to medium rivers Carp►odes cyprinus Quillback SR Occurs in pools, backwaters, and main channels of clear to turbid waters of creeks, small to large rivers, and lakes Etheostoma Riverweed Darter SC Found in rocky riffles of clear creeks and small rivers podostemone Frequently associated with riverweed (Podestemon) Exoglossum Cutlip Minnow Sc Clear creeks, streams, and small to medium rivers with maxillingua gravel, rubble, and boulder substrates Moxostoma Bigeye Jumprock T Found in warm, clear to moderately turbid, moderate artommum gradient, small to medium rivers Adults and larger juveniles congregate in deep runs and heads of pools Percina rex Roanoke Logperch E E Typically found in gravel and boulder runs of small to medium rivers Usually in warm, clear, moderate or low gradient streams Intolerant of silted substrates FRESHWATER MUSSELS Lasmigona Green floater T FSC Quiet waters Prefers small creeks and large rivers and subviridis sometimes canals Intolerant of strong currents and occurs in pools and other calm water areas Prefer gravel and sand substrate in water 1 to 4 ft deep �eur 'colltna James E E Slow to moderate current waters with relatively hard spineymussel water on sand and mixed sand and gravel substrates INSECTS So atochlora ♦g org ianaa Coppery Emerald SR A dragonfly found near creeks and other slow -moving acidic streams, in forested areas laevigata Smooth coneflower E Glades, woodlands, and open areas over mafic rocks Goldenseal SR-0 Cove forests and other rich deciduous forests !m reptans Jacob's Ladder T Moist, nutrient -rich forests such as bottomlands and is rich slopes tia Virginia Spiderwort T Rich woods on circumneutral so Notes E = e angered T = threatened FSC = federal species of concern SC = special con ern SR = significantl rare SR- — significantly rare other (j 5 N TRANTE ENERGY\LKC NPDES\R REPORT ORTS 17 DOCX 4-16 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Sources NCNHP, 2017 USFWS IPaC, 2017 NatureServe, 2017 Table 8. Protected Aquatic Species Range and Reproductive Habits Scientific Common Range Ambloplites Roanoke Bass Chowan, Roanoke, Tar, Neuse, cavifrons and Cape Fear river drainages, Virginia and North Carolina Carptodes Quillback Wide range throughout the eastern cyprinus US and Canada Etheostoma Riverweed Darter Range includes the upper Roanoke podostemone River drainage, including Roanoke system proper and Dan River system, Virginia and North Carolina Reproduction Likely spawns from mid -April to early May Spawning has been observed at 12-14 C No parental care Males mature in two years Lives about 5-6 years Eggs are adhesive and demersal Spawning occurs in deep runs over gravel and small cobble Spawns in spring and summer May migrate up small creeks to spawning areas over sand and mud bottoms in quiet waters of streams or overflow areas in bends of rivers or bays of lakes Spawning period probably April -May, also reported as late May to early June Eggs are adhesive and laid in clusters under rocks Exoglossum Cuthp Minnow Range throughout northeaster US Spawns in spring and summer Males construct maxtllingua and Canada, except most of New nests consisting of pebble mounds near cover England in areas with current Spawning occurs over upstream slopes and eggs become buried in nest mound Young emerge from the nest about a week after hatching Moxostoma Bigeye Jumprock Upper Roanoke River drainage, Spawns in March artommum Virginia and North Carolina Known in Roanoke proper and Dan systems Percina rex Roanoke Logperch Range includes the upper Roanoke, Spawns mid -April to May No parental care upper Dan, and upper Chowan river Eggs are adhesive and demersal Spawning systems Recently found in North occurs over gravel and small cobble Carolina within a few miles of the Virginia state line Lasmigona Green floater Atlantic drainages from the Cape Long term brooder (from August to June) subvtridts Fear River of North Carolina north There is recent evidence thatjuveniles of this to the Hudson River system and species can metamorphose without a host westward to the St Lawrence within the marsupia of the adult female Fish River system in New York hosts not known Pleurobema James Currently known from small Short term brooder that releases glochidia in collina spineymussel headwater tributaries of Dan and the summer Known fish hosts for this species James Rivers in North Carolina, include the rosyside dace, bluehead, mountain Virginia, and West Virginia Also redbelly dace, blacknose dace, central known from the Dan River in stoneroller, rosefin shiner, satinfin shiner, and Stokes County possibly the swallowtail shiner Sources NatureServe 2017 John Alderman 2017 The Virtual Aquarium, 2017 A�C,� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4- 1 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 4.7 Documentation of Consultation with Services [40 CFR 122.21(r)(4)(vii)] Rockingham County conducted a pre -application meeting with the USACE, NCDWQ, NCWRC, and USFWS as a part of the CWA §404/401 permitting process. USFWS and NCWRC expressed concerns about Roanoke logperch and James spineymussel. USFWS has requested freshwater mussel surveys prior to construction to determine if any of the listed species are located near the intake or discharge. If mussel species are found in the footprint of construction for the intake or discharge, they will be relocated prior to construction. Rockingham County will coordinate with USFWC and NCWRC to minimize impacts to listed species. 4.8 Methods and Quality Assurance Procedures for Field Efforts F40 CFR 122.21(r)(4)(v No new data were collected to support the biological baseline characterization; therefore, there is no need to document methods and quality assurance procedures in this subsection. 4.9 Definition of Source Water Baseline Bioloeical Characterization Data [40 CFR 122.21(r)(4)(ix)1 This report acknowledges the final 316(b) rule for existing facilities, and adds three additional subsections to the requirements of 40 CFR 122.21(r)(4). While this report has provided data to address 40 CFR 122.2 1 (r)(4)(i) through (viii) and (x) through (xii), there is no required submittal under this subsection 40 CFR 122 2 1 (r)(4)(ix). A�C� N TRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-18 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 4.10 Identification of Protective Measures and Stabilization Activities 40 CFR 122.21 ,r)(4)(M, The cooling water intake system was designed to reduce rates of impingent and entrainment at the facility. The use of closed -cycle cooling reduces impingement and entrainment through a substantial reduction (on the order of 95 percent) in cooling water needs (Table 1). In addition, the intake has been designed to meet the guidelines established by the EPA in the 316(b) rule. The through -screen velocity of less than 0.5 fps is designed to allow mobile organisms to avoid the intakes consistent with the 316(b) rule's allowed approaches to impingement best technology available. Wedgewire screens have been shown to have very little to no impingement at intake velocities of 0.5 fps due to the swimming ability of fish to detect and swim away from these velocities (Coutant, 2015; EPRI 2000). No other stabilization measures (e.g., stocking to mitigate impingement and entrainment) have been implemented. Any such measures are unnecessary given the low level of effect the intake is likely to have on the baseline biology of the Dan River. 4.11 List of Fragile Species [40 CFR 122,21(r)(4)(A)] In the final 316(b) rule, EPA identifies 14 species as fragile or having post -impingement survival rates of less than 30 percent: • Alewife • Gizzard shad • American shad • Grey snapper • Atlantic herring • Hickory shad • Bay anchovy • Menhaden • Blueback herring • Rainbow smelt • Bluefish • Round herring • Butterfish • Silver anchovy A�C,� N \PRANTE ENERGYILKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-19 It Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance Of these species only gizzard shad inhabit the Dan River and may be present near the intake. 4.12 Information Submitted to Obtain Incidental Take Exemption or Authorization from Services [40 CFR 122.21(r)(4)(xii)] The project has not sought or obtained an incidental take exemption or authorization for its cooling water intake structure from USFWS or NOAA Fisheries. �C� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 4-20 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance 5.0 References Alderman, John. 2017. Alderman Environmental Services, Inc. Personal communications with Chris Wu. March 8, 2017. Coutant, C. 2015. Hydraulic Patterns and Fish Responses Make In -River, Cylindrical Intake Screens Fish Friendly or Why Few Fish??? Prepared for Northwest Energy by Charles Coutant for presentation at EPRI conference: Clean Water Act 316(b): Conference on Engineering, Engineering, Biological and Economic Challenges of the New Existing Facility Rule. November 10-11, 2015. Duke, 2017. Dan River Fish Data, January 2016 to October 2016 Data provided by William T Russ, Foothills Coordinator, Aquatic Wildlife Diversity Program, Division of Inland Fisheries, NC Wildlife Resources Commission. January 20, 2017 Electric Power Research Institute (EPRI). 2000. Technical Evaluation of the Utility of Intake Approach Velocity as an Indicator of Potential Adverse Environmental Impact under Clean Water Act, Section 316(b). December 18, 2000. -. 2007 Cooling Water Intake Structure Area -of -Influence Evaluations for Ohio River Ecological Research Program Facilities. August 14, 2007. Huffman, R.L. 1996 Ground Water in the Piedmont and Blue Ridge Provinces of North Carolina. Published by the North Carolina Cooperative Extension Service March 1996. National Hydrography Dataset Plus (NHDPIus), 2017. NHDPlus. Accessed through Google Earth. April 2017. https://www.epa.gov/waterdata/nhdplus-national-hydrography- dataset-plus. NatureServe, Inc.. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1 NatureServe, Arlington, Virginia. http://explorer.natureserve.org. Accessed January 2017. North Carolina Division of Environmental Quality (NCDEQ) Division of Water Resources (DWR). 2017. Surface Water Classifications Map. Accessed online: April 2017. https :Hdeq.nc. gov/about/div is ions'water-resources/planning/classification- standards/classifications. North Carolina Natural Heritage Program (NCNHP). 2017. http://www.ncnhp.org/. Accessed: January 24, 2017. N \PRANTEE ENERGY\L.KC NPDES\R REPORTS\R REPORTS O42017 DOCX 5-21 Rockingham County Dan River Intake Rockingham County Submittals Related to Section 316(b) Compliance North Carolina Wildlife Resources Commission (NCWRC), 2017. Fish and Shellfish Collections made in the Dan River November 1984 to June 2016. Data provided by William T. Russ, Foothills Coordinator, Aquatic Wildlife Diversity Program, Division of Inland Fisheries, NC Wildlife Resources Commission. January 20, 2017. Reid, J.0 , R.C. Milici. 2008. Hydrocarbon Source Rocks in the Deep River and Dan River Triassic Basins, North Carolina 2008. U S Geological Survey Open -File Report 2008- 1108, 28p. Reid, J C., K. B. Taylor, J. D. Simons. 2011. North Carolina Shale Gas: Dan River Basin, Stokes and Rockingham Counties North Carolina Geological Survey, Raleigh. November, 2011. Rockingham County. 2010. A Land Use Plan for Managing Growth: Rockingham County, North Carolina. Rockingham County Department of Planning. Accessed online: April 2017. http://www.co.rockingham.nc.us/. Rohde et al, 2003. An Annotated List of the Fishes Known from the Dan River in Virginia and North Carolina (Blue Ridge/Piedmont Provinces). Fred Rohde, Rudolf Arndt, David Coughlan, Scott Smith Southeastern Fisheries Council Proceedings. Number 45. April 2003. Rohde et al, 2001. Longitudinal Succession of Fishes in the Dan River in Virginia and North Carolina (Blue Ridge/Piedmont Provinces). Fred Rohde, Rudolf Arndt, Scott Smith. Southeastern Fisheries Council Proceedings. Number 42. July 2001. U.S. Environmental Protection Agency (EPA) 2001. National Pollutant Discharge Elimination System: Regulations Addressing Cooling Water Intake Structures for New Facilities; Final Rule. Federal Register. Volume 66, pp. 65256-65345. December 18, 2001 I. 2014a. National Pollutant Discharge Elimination System (NPDES) General Permits for Noncontact Cooling Water Discharges. MAG250000 AND NHG250000 https://www3 epa.gov/regionl/npdes/nccwgp/2014NCCWGeneralPermit.pdf. Accessed September 9, 2016. -. 2014b. Response to Comments on Draft National Pollutant Discharge Elimination System (NPDES) General Permit for Noncontact Cooling Water (NCCW) Discharges. MAG250000 and NHG250000 https://www3.epa.gov/regionl/npdes/nccwgp/2014NCCWGPRTC.pdf. Accessed September 9, 2016. 2016. Information for Planning and Conservation (IPaQ. Fish and Wildlife Service https-Hecos.fws.gov/ipac/. Accessed January 2016 N \PRANTE ENERGYU.KC NPDES\R REPORTS\R REPORTS O42017 DOCX 5 -22 Rockingham County Rockingham County Dan River Intake Submittals Related to Section 316(b) Compliance . 2016. Information for Planning and Conservation (IPaC) Fish and Wildlife Service https://ecos.fws.gov/ipac/. Accessed August 29, 2016. U.S. Geological Survey (USGS), 2017 USGS Water Data for the Nation. Accessed online. April 2017. https://waterdata.usgs gov/nwis/qw. The Virtual Aquarium 2017. http://www.webl enre.vt.edu/efish/families/riverweed.html accessed March 13, 2017. Zeitoun, I.H., J A. Gulvas, and D.B. Roarabaugh. 1981 Effectiveness of Fine Mesh Cylindrical Wedge -Wire Screens in Reducing Entrainment of Lake Michigan Ichthyoplankton. Canadian Journal of Fisheries and Aquatic Sciences, 1981, 38(1): 120-125. A�C,� N \PRANTE ENERGY\LKC NPDES\R REPORTS\R REPORTS O42017 DOCX 5 -23