Loading...
HomeMy WebLinkAboutNC0090131_Fact Sheet_20230519 Fact Sheet NPDES Permit No. NCO090131 Permit Writer/Email Contact Nick Coco,nick.coco@ncdenr.gov Date: May 16,2023 Division/Branch:NC Division of Water Resources/NPDES Municipal Permitting Fact Sheet Template: Version 09Jan2017 Permitting Action: ❑ Renewal ❑ Renewal with Expansion ® New Discharge ❑ Modification(Fact Sheet should be tailored to mod request) Note: A complete application should include the following: • For New Dischargers,EPA Form 2A or 2D requirements,Engineering Alternatives Analysis,Fee • For Existing Dischargers (POTW),EPA Form 2A, 3 effluent pollutant scans,4 2nd species WET tests. • For Existing Dischargers (Non-POTW),EPA Form 2C with correct analytical requirements based on industry category. Complete applicable sections below. If not applicable, enter NA. 1. Basic Facility Information Facility Information Applicant/Facility Name: City of Kings Mountain/Mill Creek Wastewater Treatment Plant (WWTP) Applicant Address: PO Box 429,Kings Mountain,NC 28086 Facility Address: Jim Patterson Road, Grover,NC 28073 Permitted Flow: 4.0 MGD Facility Type/Waste: MAJOR Municipal; 100% domestic Facility Class: Grade IV Biological Water Pollution Control System Treatment Units: One manual bar screen, one automatic bar screen, grit removal system, influent flow measurement, splitter box,two sequencing batch reactors (SBRs),rotating disc filters, dual train UV disinfection, effluent weir and Parshall flume, cascade aeration,two sludge holding tanks,belt press Pretreatment Program(Y/N) N County: Cleveland Region I Mooresville Briefly describe the proposed permitting action and facility background.• The City of Kings Mountain applied on August 3, 2022 for a new discharge,to be permitted under NPDES permit NC0090131, for the proposed Mills Creek WWTP at 4.0 MGD with an expansion tier at 6.0 MGD. Please note that review of flow projections has determined the 6.0 MGD expanded flow tier is not justified at this point. As such,the 6.0 MGD expanded flow tier has not been included as part of this permit. This project is receiving funding via the American Rescue Plan Act(ARPA). The project will also include the termination of two existing NPDES permits:NC0065242 Grover WWTP and NC0032867 Kings Mountain Travel Plaza plant. Flow projections are discussed in detail below in Antidegradation Review. This proposed facility will serve a population of approximately 14,400 residents in the southeastern area of Cleveland County(Project South service area), including the towns of Grover and Kings Mountain. The permittee indicated in their permit application that no wastewater would be received from significant Page 1 of 12 industrial users. Treated domestic wastewater is proposed for discharge via Outfall 001 into Dixon Branch, a class C water in the Broad River Basin. Outfall 001 is located approximately 1.5 miles upstream of the NC/SC state border. Sludge Disposal: Sludge is to be sent to the Self-McNeilly Landfill. 2. Receiving Waterbody Information: Receiving Waterbody Information Outfalls/Receiving Stream(s): Outfall 001 Dixon Branch Stream Index: 9-54-3 Stream Classification: C Drainage Area(mi): 1.31* Summer 7Q10(cfs) 0.30* Winter 7Q10(cfs): 0.50* 30Q2 (cfs): 0.65* Average Flow(cfs): 1.65* IWC (%effluent): 90 2022 303(d) listed/parameter: Not listed in NC 2022 303d List or SC 2018 303d List Subject to TMDL/parameter: Yes- State wide Mercury TMDL implementation. Subbasin/HUC: 03-08-05/03050105 USGS Topo Quad: G13NW Grover,NC *Based on updated USGS stream statistics provided on August 24,2020(attached). 3. Effluent Data Summary As this is a proposed brand new facility,no effluent data is available. Speculative limits were provided to the City by the Division on January 7,2022 for the 4.0 MGD and 6.0 MGD flow tier. These limits are found below in Table 1. Please note that the 6.0 MGD flow tier is not being incorporated into the permit at this time. TABLE 1. Speculative Limits for City of Kings Mountain proposed new facility. Effluent Characteristic Effluent Limitations Monthly Weekly Daily Average Average Maximum Flow 4.0/6.0 MGD BOD5 5.0 mg/L 7.5 mg/L NH3 as N(Apr.-Oct.) 1.0 mg/L 3.0 m NH3 as N(Nov. -Mar.) 1.8 mg/L 5.7 mg/L Dissolved Oxygen 6.0 mg/L minimum daily average) Total Phosphorus 1.0 mg/L Monitor& Report(mg/1) TSS 30 mg/L 4.5 mg/L TRC 17 ug l Fecal coliform(geometric 200/100 ml 400/100 ml mean) Chronic Toxicity Pass/Fail 90% (Quarterly test Page 2 of 12 These speculative limits act as the basis of design for the facility. In their EAA,the City notes that in order to meet the speculative limits, a tertiary treatment process is proposed. The secondary treatment utilized is proposed to be a Sequencing Batch Reactor(SBR)process. Design calculations are based on a continuous flow system(ICEAS)manufactured by Sanitaire. The treatment process is proposed to include the following: 1. Headworks Headworks consisting of a dual channel screen system(one automatic, one manual), grit system, and influent flow measurement. The headworks will be designed for a hydraulic capacity of 6.0 MGD with a 2.5 peaking factor. 2. Secondary Treatment Process—The treatment process will initially be designed for a flow of 4.0 MGD in two (2) -2.0 MGD trains. The layout will allow for the addition of a third 2 MGD basin in the future to increase the capacity to 6 MGD. A splitter box will be located upstream of the SBR with the ability to equally split the flow among 3 trains (two initial, one future). The preliminary design is based on the ICEAS SBR manufactured by Sanitaire. The design is preferred because it allows continuous flow to all basins without the need for automatic valves to control the flow. The treatment system will be designed for an initial capacity of 4 MGD, and expandable to 6 MGD in the future. Hydraulically the system will be designed with a peaking factor of 2.5 MGD. The ICEAS SBR includes complete fine bubble aeration system,two submerged horizontal propeller type mixers,waste activated sludge(WAS)pumps, and motor controlled horizontal decanter. A surge tank will be included in the design. The surge tank will have sufficient capacity to allow the ICEAS to operate with periodic high-rate discharges from the SBR and control the discharge rate to the filters and UV system using a flow control valve. The control valve will maintain a steady state flow through the filters and the disinfection system. The SBR will be automatically controlled to reduce total nitrogen(TN)in the discharge. To accomplish TN reduction,nitrification and denitrification must occur. Instrumentation will be installed to provide feedback to the SBR control system. 3. Tertiary Treatment/Rotating Disc Filters—Stainless steel mesh or cloth rotating disc filters will be installed to provide tertiary treatment of the SBR discharge. Redundant filters will be provided to provide treatment for the design flow rate with the largest unit out of service. Backwash flow from the filters will be returned to the headworks of the plant. 4. Disinfection—Disinfection can be accomplished using a chlorine contact basin followed by dechlorination prior to discharge or using a UV disinfection system. The use of UV disinfection is preferred. A dual train UV system will be included with each train containing two cassettes with a capacity of 2 MGD per cassette. The UV system will include a cassette removal and cleaning system with the ability to remove, inspect, and clean each cassette. 5. Post Flow Measurement and Re-Aeration—A flow measurement device and a post aeration system will follow the disinfection process. Flow measurement will be provided by a weir flow device or a Parshall flume. Aeration will be provided by using fine bubble diffusers installed in effluent trough or with the installation of a cascade aerator. A cascade aerator is the preferred system, ensuring adequate re- aeration prior to discharge. 6. Sludge Handling—Waste activated sludge is removed from the SBR process during each 4- hour(approximately) cycle. WAS removed from the basin will have an average concentration of. 85%. WAS will be pumped to one of two sludge holding tanks, each with a volume of 750, 000 gpd. Each tank will include an aeration system and a decanting system. The aeration/decanting process will be controlled through an instrumentation system with the goal of limiting the return Page 3 of 12 of phosphorus to the headworks of the plant. Through decanting,the sludge concentration will be increased to approximately 2.5%. Concentrated sludge will be dewatered using a belt press or a centrifuge. The dewatered sludge will be disposed of at a permitted facility. Decant from the sludge basins and dewatering system will be returned to the headworks. Review of DMR data from July 2018 through January 2023 for the Grover WWTP (NC0065242) are summarized in Table 2. Table 2. Data Sum ma Grover WWTP Parameter Units Average Max Min Influent BOD mg/1 472 1382 46 Influent NH3N mg/1 40 133 19.25 Summer Influent NH3N mg/1 36 66 14.25 Winter Influent TSS I mg/1 1 338 2200 46.5 Effluent TN mg/1 18.4 52.7 <2 Effluent TP mg/1 3.4 7.86 0.96 Influent BOD, ammonia, and TSS data, as well as effluent TN and TP data are summarized for reference of what may be present in the influent of the proposed Mill Creek WWTP,though these values may be variable when considering the larger service area.No such data was available for the Kings Mountain Travel Plaza(NC0032867). 4. Instream Data Summary Instream monitoring may be required in certain situations, for example: 1)to verify model predictions when model results for instream DO are within 1 mg/1 of instream standard at full permitted flow;2)to verify model predictions for outfall diffuser; 3)to provide data for future TMDL; 4)based on other instream concerns. Instream monitoring may be conducted by the Permittee, and there are also Monitoring Coalitions established in several basins that conduct instream sampling for the Permittee(in which case instream monitoring is waived in the permit as long as coalition membership is maintained). If applicable, summarize any instream data and what instream monitoring will be proposed for this permit action: As this is a proposed brand new facility,no instream data are available. As this proposed facility is Grade IV per 15A NCAC 08G .0302, instream monitoring for dissolved oxygen,temperature and fecal coliform is proposed at a frequency of three times per week during June,July,August, and September, and once per week during the rest of the year. Additionally, instream monitoring for TKN,Nitrate+Nitrite, and total phosphorous is proposed at a frequency of once per quarter. For calculation of dissolved metals, upstream hardness sampling has been proposed at a frequency of once per quarter. Based on review of the 2021 Level B model identifying the DO sag point occurring 0.4 miles downstream from the outfall, instream sampling will be collected upstream at least 100 feet above the outfall and downstream at Jim Patterson Road. Instream conductivity monitoring is also listed in 15A NCAC 08G .0302. However,per the 2002 Guidance Regarding Conductivity and Fecal Coliform Monitoring, as the facility is proposed as 100% domestic, instream conductivity monitoring has not been added to the permit. Should the facility begin accepting industrial wastewater, instream conductivity monitoring should be added to the permit. Is this facility a member of a Monitoring Coalition with waived instream monitoring(YIN):N Page 4 of 12 Name of Monitoring Coalition: NA 5. Compliance Summary Summarize the compliance record with permit effluent limits (past 5 years): NA Summarize the compliance record with aquatic toxicity test limits and any second species test results (past 5 years):NA Summarize the results from the most recent compliance inspection:NA 6. Water Quality-Based Effluent Limitations (WQBELs) Dilution and Mixing Zones In accordance with 15A NCAC 2B.0206,the following streamflows are used for dilution considerations for development of WQBELs: 1 Q 10 streamflow(acute Aquatic Life); 7Q 10 streamflow(chronic Aquatic Life;non-carcinogen HH); 30Q2 streamflow(aesthetics); annual average flow(carcinogen,HH). If applicable, describe any other dilution factors considered(e.g., based on CORMLXmodel results):NA If applicable, describe any mixing zones established in accordance with 15A NCAC 2B.0204(b): NA Oxygen-Consuming Waste Limitations Limitations for oxygen-consuming waste(e.g., BOD) are generally based on water quality modeling to ensure protection of the instream dissolved oxygen(DO)water quality standard. Secondary TBEL limits (e.g., BOD=30 mg/1 for Municipals)may be appropriate if deemed more stringent based on dilution and model results. Ifpermit limits are more stringent than TBELs, describe how limits were developed: Assimilative capacity to protect the instream dissolved oxygen standard of 5.0 mg/L was modeled with a 2021 NC specific Streeter-Phelps model. The resultant limits are summer limits of 5 mg/L(BOD5) and 1 mg/I(NH3-N) and winter limits of 10 mg/L(BOD5)and 1.8 mg/L(NH3-N). These limits are proposed for the 4.0 MGD flow. Ammonia and Total Residual Chlorine Limitations Limitations for ammonia are based on protection of aquatic life utilizing an ammonia chronic criterion of 1.0 mg/1(summer) and 1.8 mg/1(winter). Acute ammonia limits are derived from chronic criteria, utilizing a multiplication factor of 3 for Municipals and a multiplication factor of 5 for Non-Municipals. Limitations for Total Residual Chlorine(TRC)are based on the NC water quality standard for protection of aquatic life(17 ug/1) and capped at 28 ug/1(acute impacts). Due to analytical issues,all TRC values reported below 50 ug/1 are considered compliant with their permit limit. Describe any proposed changes to ammonia and/or TRC limits for this permit renewal: TRC requirements have been assessed for the 4.0 MGD flow tier a daily maximum limit of 17 ug/L has been applied based on the speculative limits provided by the Division on January 7,2022. Please see Oxygen-Consuming Waste Limitations above for background on ammonia limits. Reasonable Potential Analysis(RPA)for Toxicants If applicable, conduct RPA analysis and complete information below. The need for toxicant limits is based upon a demonstration of reasonable potential to exceed water quality standards, a statistical evaluation that is conducted during every permit renewal utilizing the most recent Page 5 of 12 effluent data for each outfall. The RPA is conducted in accordance with 40 CFR 122.44(d) (i). The NC RPA procedure utilizes the following: 1)95% Confidence Level/95%Probability; 2)assumption of zero background; 3)use of%2 detection limit for"less than"values; and 4) streamflows used for dilution consideration based on 15A NCAC 2B.0206. Effective April 6,2016,NC began implementation of dissolved metals criteria in the RPA process in accordance with guidance titled NPDES Implementation of Instream Dissolved Metals Standards, dated June 10,2016. As this is a new facility with no discharge to date,no effluent data is available. Per 40 CFR 122.210)(4), "for POTWs applying prior to commencement of discharge, data shall be submitted no later than 24 months after the commencement of discharge."As such, a requirement has been added to the permit that an effluent pollutant scan be conducted and submitted to the Division within 24 months of the commencement of discharge, and once per year for the 2 following years. Toxici , Testing Limitations Permit limits and monitoring requirements for Whole Effluent Toxicity(WET)have been established in accordance with Division guidance(per WET Memo, 8/2/1999). Per WET guidance, all NPDES permits issued to Major facilities or any facility discharging"complex"wastewater(contains anything other than domestic waste)will contain appropriate WET limits and monitoring requirements,with several exceptions. The State has received prior EPA approval to use an Alternative WET Test Procedure in NPDES permits,using single concentration screening tests,with multiple dilution follow-up upon a test failure. Describe proposed toxicity test requirement: Quarterly chronic toxicity testing at 90%effluent concentration is proposed. Testing is to be conducted during the months of January,April, July and October. Mercury Statewide TMDL Evaluation As this is a new facility with no discharge to date,no effluent data is available. Low Level mercury testing is required as part of the effluent pollutant scan requirement. A Mercury Minimization Plan (MMP) is proposed to mitigate the potential for elevated total mercury levels upon facility startup. Other TMDL/Nutrient Management Strategy Considerations If applicable, describe any other TMDLs/Nutrient Management Strategies and their implementation within this permit: As the proposed discharge is approximately 1.5 miles above the SC/NC border, SCDHEC was consulted with regard to nutrient management. To protect downstream uses,the South Carolina Department of Health and Environmental Control recommends that total phosphorus be limited to 1.0 mg/L. Other WQBEL Considerations If applicable, describe any other parameters of concern evaluated for WQBELs: As required by Session Law 2018-5, Senate Bill 99, Section 13.1(r), every applicant shall submit documentation of any additional pollutants for which there are certified methods with the permit application if their discharge is anticipated. However, as no effluent data have been collected due to no discharge existing,the chemical addendum is not applicable. As the Mill Creek WWTP has a proposed discharge 1.5 miles upstream of the SC/NC state border, , monitoring of PFAS chemicals will be added to the permit at a frequency of quarterly. Since an EPA method for sampling and analyzing PFAS in wastewater is not currently available,the PFAS sampling Page 6 of 12 requirement in the Permit includes a compliance schedule which delays the effective date of this requirement until the first full calendar quarter beginning 6 months after EPA has a final wastewater method in 40 CFR136 published in the Federal Register. This date may be extended upon request and if there are no NC-certified labs. If applicable, describe any special actions (HQW or ORW) this receiving stream and classification shall comply with in order to protect the designated waterbody: NA If applicable, describe any compliance schedules proposed for this permit renewal in accordance with 15A NCAC 2H.0107(c)(2)(B), 40CFR 122.47, and EPA May 2007 Memo:NA If applicable, describe any water quality standards variances proposed in accordance with NCGS 143- 215.3(e) and 15A NCAC 2B.0226 for this permit renewal:NA 7. Technology-Based Effluent Limitations (TBELs) Are concentration limits in the permit at least as stringent as secondary treatment requirements (30 mg/l BODS/TSS for Monthly Average, and 45 mg/l for BODS/TSS for Weekly Average). YES If NO,provide a justification for alternative limitations (e.g., waste stabilization pond). NA Are 85%removal requirements for BOD51TSS included in the permit? YES If NO,provide a justification (e.g., waste stabilization pond). NA 8. Antidegradation Review (New/Expanding Discharge): The objective of an antidegradation review is to ensure that a new or increased pollutant loading will not degrade water quality. Permitting actions for new or expanding discharges require an antidegradation review in accordance with 15A NCAC 213.0201. Each applicant for a new/expanding NPDES permit must document an effort to consider non-discharge alternatives per 15A NCAC 2H.0105(c)(2). In all cases, existing instream water uses and the level of water quality necessary to protect the existing use is maintained and protected. If applicable, describe the results of the antidegradation review, including the Engineering Alternatives Analysis (EAA) and any water quality modeling results: The proposed expansion is funded via the American Rescue Plan Act(ARPA)and is not subject to review under the National Environmental Policy Act(NEPA). As ARPA funding for this facility is subject to Chapter 159G and G.S. 113-12(h),no State Environmental Policy Act(SEPA)review is required. An Engineer's Alternatives Analysis (EAA)was submitted by MBD Consulting Engineers,P.A. (MBD), the consulting firm hired by the City of Kings Mountain, on August 3,2022. In their EAA,MBD noted that based on Census data and the NC Office of State Budget and Management(OSBM), Cleveland County grew at a rate of 1.1%in last 10 years. MBD has noted the belief that growth in this area was impacted by the lack of sewer service available, including the growth in the Town of Grover. Upon their review of growth trends in counties adjoining this area on both sides of the North Carolina/South Carolina state line, MBD notes that both areas are growing at higher rates. Gaston County,North Carolina grew at a rate of 9.9%over the past 10 years. York County, South Carolina grew at a rate of 27% for the same period. Growth occurring in adjoining counties combined with the impact of planned development along I-85 in this area of Cleveland County will increase the demand for infrastructure in southeastern Cleveland County. Sewer availability will impact the growth rate for the Project South service area. Based on a 20-year growth projection,MBD projects a need for residential flow of approximately 2.8 MGD by 2042. This considers the 2020 census data for the Project South service area showing a population of approximately 13,700 residents, an assumed 5%population growth rate based on neighboring areas,2.3 residents per service, 320 gallons per day per service, and an 85%connection rate. Page 7 of 12 NC OSBM population growth data was reviewed by Division staff to accompany the submitted census information. Review of Cleveland County(specifically Kings Mountain and Grover)echoed the population growth of 1.1%indicated by MBD. Review of Gaston County(specifically Bessemer City and Gastonia, as they are near the service area)reported similar growth. The growth projected by MBD appears to assume that growth in the greater Gaston County will influence the service area,which may overestimate demand in the service area. Based on a 5%growth rate, a 2020 Project South service area population of approximately 13,700 residents, an assumed 85%connection rate, a flow rate of 70 gallons per person per day, and a 15%reserve flow for potential industrial and commercial users, a flow demand of approximately 2.1 MGD was calculated,which is relatively consistent with the future flow demand estimated by MBD. In their permit application and EAA,the City of Kings Mountain requests a 4 MGD flow tier and an expanded flow tier to 6 MGD. At this time, it does not appear necessary to incorporate a 6 MGD expanded flow tier. As the 2.8 MGD flow projection is only a result of an assumed growth rate based on faster growing adjacent areas, it is not certain whether the existence of this WWTP will indeed impact growth in the Project South service area.As such, only a 4 MGD flow tier is proposed,but a 6 MGD flow may become necessary at a future date after additional growth information is developed. The following alternatives were evaluated for the proposed discharge: Alternative Description 20- ear NPV Transfer flow and treatment to nearbyPilot Creek WWTP $67,368,600 Land Application $91,163,200 Direct Discharge to Surface Waters $46,933,600 Transfer Flow and Treatment to nearby Pilot Creek WWTP: The Pilot Creek WWTP is a 6.0 MGD extended aeration, activated sludge treatment plant that utilizes lagoons for aeration followed by clarification, disinfection, and discharge. The current average daily demand on the facility is 2.5 MGD. A reserve of 1.0 MGD is included in the allocated capacity for Pilot Creek which would leave approximately 2.5 MGD of capacity available for Project South. The existing service area for the Pilot Creek WWTP extends to the proposed northern boundary of the Project South service area. Flow collected for Project South would have to be transferred back to the WWTP due to capacity issues in the existing collection system. The topography in the southeastern portion of Cleveland County dictates the design of the sewer collection system for Project South. Pumping the wastewater back to the Pilot Creek WWTP will require overcoming the friction and static head loss. The location of the primary collection pump station will be at an elevation that is substantially lower than the high point of the system. The route that the force main would take to cross I-85,which would be the high point of the force main system. In order to accommodate the topography and the friction loss in the proposed force main system,two pump stations will be required to enable the wastewater to be pumped to the high point. Once it reaches the high point,the system would have the static head to deliver the wastewater to treatment plant without any additional pumping. The two pump stations would be major sites that will include triplex pump stations with screening systems and emergency generation(or bypass pumping) systems. Depending on the availability of sites,the location of the second pump station in the series may benefit the design of the Project South collection system but would not impact the location of the primary pump station. The cost of the pump stations and collection system was estimated to be$26,882,000. Construction of upgrades at the Pilot Creek WWTP was estimated to cost$24,087,000. Land Application: Soil type and land availability were considered when evaluating the land application option. Soil information was obtained from the " Custom Soil Resource Report for Cleveland County, North Carolina and Gaston County,North Carolina"prepared by USDA. The predominate soil types in southeastern Cleveland County are shown below. The soils in this area are not generally receptive to Land Application systems with high application volumes. The predominate soil types are listed below. Page 8 of 12 Soil Type Name Description Slope Capacity of Most Limitin La er K sat HhB Hulett Gravelly Sandy Loan 2-8% 0.57-1.98 GrD Grover Gravelly Sandy Loan 2-8% 0.57-1.98 HtC Hulett Gravelly Sand Loan 8-15% 0.57-1.98 HuC Hulett Soil Complex 4-15%(very rock 0.57-1.98 The above soils fall into category C. The actual application rate would be determined by a soils engineer and on site sampling. For this study, an application rate of 0.5 inches per acre per week was used for evaluating the technical and economic viability of this option. At a rate of 0.5 inches per acre per week, a total of 2,062 acres would be required for land application.Adding addition property for buffer would increase the required acreage to approximately 2,475 acres total. In addition to the area required for land application, a 30-day holding pond(210 MG)would be required to be constructed on or near the site, as well as an irrigation pump station. Based on current county GIS information,it would be difficult to acquire a contiguous 2,500 acre site. The cost of this option includes the cost of construction a new WWTP designed to meet the anticipated treatment requirements for an Non-Discharge permit and the cost for the land application system. The estimated construction cost of land application for the 4.0 MGD discharge including effluent pumping, a 30- day storage, land, clearing, seeding, and irrigation system is $21,158,200. The total costs for building a 4 MGD WWTP and disposing of the effluent via land application is estimated to be $65,863,800. Direct Discharge to Surface Waters: The cost of the treatment facility begins at the headworks and extends through the proposed treatment process to the discharge and includes the sludge handling facility and all ancillary systems. The treatment plant costs used in this analysis are similar for both the land application and surface discharge options. While there may be slight differences in the treatment plants costs,the difference would not be significant and would not impact this evaluation. The total project cost for the WWTP include disinfection and discharge is estimated to be $26,149,100. The total costs include all sitework piping, structures,process equipment,buildings, electrical, controls, etc. required for a complete treatment process. The most economically feasible and chosen option was the construction of the Mill Creek WWTP and direct discharge into Dixon Branch. The Division has reviewed the alternatives and concurs with this decision. Please note that wastewater reuse as a disposal option was evaluated and found to be infeasible, as the City of Kings Mountain does not currently have a reuse program that would allow for the disposal of larger quantities of treated effluent. However, The WWTP will be designed to reuse treated wastewater for wash down throughout the plant including any dewatering activities. Reuse water will also be used as irrigation on site. 9. Antibacksliding Review: Sections 402(o)(2) and 303(d)(4)of the CWA and federal regulations at 40 CFR 122.44(1)prohibit backsliding of effluent limitations in NPDES permits. These provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permit,with some exceptions where limitations may be relaxed(e.g.,based on new information,increases in production may warrant less stringent TBEL limits, or WQBELs may be less stringent based on updated RPA or dilution). Are any effluent limitations less stringent than previous permit(YESNO): NO If YES, confirm that antibacksliding provisions are not violated:NA Page 9 of 12 10. Monitoring Requirements Monitoring frequencies for NPDES permitting are established in accordance with the following regulations and guidance: 1) State Regulation for Surface Water Monitoring, 15A NCAC 213.0500;2) NPDES Guidance,Monitoring Frequency for Toxic Substances (7/15/2010 Memo); 3)NPDES Guidance, Reduced Monitoring Frequencies for Facilities with Superior Compliance(10/22/2012 Memo); 4)Best Professional Judgement(BPJ). Per US EPA(Interim Guidance, 1996),monitoring requirements are not considered effluent limitations under Section 402(o)of the Clean Water Act, and therefore anti- backsliding prohibitions would not be triggered by reductions in monitoring frequencies. For instream monitoring,refer to Section 4. Monitoring frequencies proposed reflect those of a Grade IV POTW as identified in 15A NCAC 02B .0508. 11. Electronic Reporting Requirements The US EPA NPDES Electronic Reporting Rule was finalized on December 21, 2015. Effective December 21, 2016,NPDES regulated facilities are required to submit Discharge Monitoring Reports (DMRs) electronically. While NPDES regulated facilities would initially be required to submit additional NPDES reports electronically effective December 21, 2020,EPA is proposing to extend this deadline from December 21,2020,to December 21,2025. This permit contains the requirements for electronic reporting, consistent with Federal requirements. The current compliance date will be extended if the implementation date is extended as a final regulation change in the federal register. 12.Summary of Proposed Permitting Actions: Table 4. Current Permit Conditions and Proposed Changes 4.0 MGD Parameter Proposed Condition Basis for Condition Flow MA 4.0 MGD 15A NCAC 213 .0505 BOD5 MA 5.0 mg/l WQBEL. Based on 2021 Level B model; 2022 Speculative WA 7.5 mg/1 Limits and 2023 WLA spreadsheet; Surface Water Monitoring, _ Monitor and Report Daily 15A NCAC 2B. 0500 NH3-N Summer: WQBEL. Based on 2021 Level B model and ammonia toxicity; MA 1.0 mg/l 2022 Speculative Limits and 2023 WLA spreadsheet; Surface WA 3.0 mg/l Water Monitoring, 15A NCAC 2B. 0500 Monitor and Report Daily Winter: MA 1.8 mg/l WA 5.7 mg/1 Monitor and Report Dail TSS MA 30 mg/l TBEL. Secondary treatment standards/40 CFR 133 / 15A NCAC WA 45 mg/l 2B .0406; 2022 Speculative Limits; Surface Water Monitoring, Monitor and Report Daily 15A NCAC 2B. 0500 Fecal coliform MA 200/100ml WQBEL. State WQ standard, 15A NCAC 213; Surface Water WA 400/100ml Monitoring, 15A NCAC 2B. 0500 Daily monitoring DO DA>6.0 mg/L WQBEL. State WQ standard, 15A NCAC 213; 2022 Speculative Monitor and Report Daily Limits; Surface Water Monitoring, 15A NCAC 2B. 0500 Total Residual DM 17 ug/L WQBEL. State WQ standard, 15A NCAC 2B; 2022 Speculative Chlorine I Monitor and Report Daily I Limits; Surface Water Monitoring, 15A NCAC 2B. 0500 Page 10 of 12 Temperature Monitor and Report Daily Surface Water Monitoring, 15A NCAC 2B. 0500 pH 6—9 SU WQBEL. State WQ standard, 15A NCAC 213; Surface Water Monitor and Report Daily Monitoring, 15A NCAC 2B. 0500 TKN Monitor and Report For calculation of Total Nitrogen Quarterly NO2+NO3 Monitor and Report For calculation of Total Nitrogen Quarterly Total Nitrogen Monitor and Report Surface Water Monitoring, 15A NCAC 2B. 0500 Quarterly Total MA 1.0 mg/L WQBEL. 2022 Agreement with SCDHEC Phosphorous Monitor and Report Weekly PFAS Quarterly monitoring with delayed Evaluation of HAS contribution: new facility; Implementation implementation delayed until after EPA certified method becomes available. Chronic Chronic limit, WQBEL.No toxics in toxic amounts. 15A NCAC 2B Toxicity 90%effluent Effluent Three times per permit 40 CFR 122 Pollutant Scan cycle if the facility is in operation,with the first occurring within 24 months of commencement of discharge Mercury MMP Special Condition Consistent with 2012 Statewide Mercury TMDL Minimization Implementation;New Municipality with Q>2 MGD Plan(MMP) Notification of Special Condition A.(6.) New Discharger;Notify Division at least 7 days prior to Discharge commencement of discharge Electronic Electronic Reporting In accordance with EPA Electronic Reporting Rule 2015. Reporting I Special Condition MGD—Million gallons per day,MA- Monthly Average,WA—Weekly Average,DM—Daily Max, QA —Quarterly Average,DA—Daily Average,AA—Annual Average 13. Public Notice Schedule: Permit to Public Notice: Month xx,2023 Per 15A NCAC 2H .0109 & .0111, The Division will receive comments for a period of 30 days following the publication date of the public notice.Any request for a public hearing shall be submitted to the Director within the 30 days comment period indicating the interest of the party filing such request and the reasons why a hearing is warranted. 14. Fact Sheet Addendum (if applicable): Were there any changes made since the Draft Permit was public noticed(Yes/No):NO If Yes, list changes and their basis below:NA Page 11 of 12 15. Fact Sheet Attachments (if applicable): • 2022 Speculative Limitations Letter • SCDHEC Correspondence • Correspondence with City • Additional information provided by City Page 12 of 12 12/22/21, 12:24 PM Mail-Hill, David A-Outlook [External] Fw:Dixon Branch...phosphorus(per our discussion today) Cantrell,Wade<CANTREWM@dhec.sc.gov> Thu 10/21/2021 8:25 AM To: Hill,David A<david.hill@ncdenr.gov>;Montebello,Michael J<Michael.Montebello@ncdenr.gov> Cc: Baumann,Matthew S.<baumanms@dhec.sc.gov> CAUTION:External email.Do not click links or open attachments unless you verify.Send all suspicious email as an attachment to Report Spam. David,Mike- FYI. The WEC analysis proposed 1 mg/LTP limits. Thanks, Wade Wade Cantrell 303d,Modeling&TMDL Section Manager Division of Water Quality-Bureau of Water S.C.Dept.of Health&Environmental Control Office:(803)898-3548 Connect:www.scdhec.gov Facebook Twitter From:Cantrell,Wade<CANTREWM@dhec.sc.gov> Sent:Thursday,October 21,20218:18 AM To:jdebessonet@water-ec.com<jdebessonet@water-ec.com>;Baumann,Matthew S.<baumanms@dhec.sc.gov>;MGoodrich@Water-EC.com<M Goodrich @Water-EC.com> Cc:joelwood@comporium.net<joelwood@comporium.net> Subject:Re:Dixon Branch...phosphorus(per our discussion today) Jeff- The WEC analysis and proposed TP limits address concerns about incremental impacts to downstream waters. It is also noted that the proposed TP limits are forward-thinking and would represent a higher level of treatment than current discharges in the basin. These limits would likely put the facility in a defensible position in any future re-allocation or TMDL scenario. However,due to recent proposals in the basin,including a major new proposal we are evaluating now,we are having to look at our approach to cumulative impacts. Under the circumstances,I am not sure at this point if DHEC would comment on a draft permit with the proposed limits or if so,what the comments would be. In any case,the advance communication and WEC analysis are helpful. Suggest keeping communication open on this. Thanks, Wade Wade Cantrell 303d,Modeling&TMDL Section Manager Division of Water Quality-Bureau of Water S.C.Dept.of Health&Environmental Control Office:(803)898-3548 Connect:www.scdhec.gov Facebook Twitter From:Jeff deBessonet<jdebessonet@water-ec.com> Sent:Thursday,September 16,2021 12:26 PM To:Baumann,Matthew S.<baumanms@dhec.sc.gov>;Cantrell,Wade<CANTREWM@dhec.sc.gov>;MGoodrich@Water-EC.com<MGoodrich@Water-EC.com> Cc:joelwood@comporium.net<joelwood@comporium.net> Subject:RE:Dixon Branch...phosphorus(per our discussion today) ***Caution.This is an EXTERNAL email.DO NOT open attachments or click links from unknown senders or unexpected email.*** Matt B and Wade C: Please review the attached—based on our conversation. Look forward to your feedback. Thanks. --------------------------------------------- Jeff deBessonet,P.E. Senior Engineer Water Environment Consultants P.O.Box 2221 Mount Pleasant,SC 29465 Cell:803-351-1067 Office:843-375-9022 www.water-ec.com Specialized Engineering and Permitting Support in the Water Environment From:Baumann,Matthew S.<baumanms@dhec.sc.gov> Sent:Friday,August 20,2021 10:51 AM To:Jeff deBessonet<jdebessonet@water-ec.com>;Cantrell,Wade<CANTREWM@dhec.sc.gov>;Matt Goodrich<mgood rich @water-ec.com> Subject:RE:Dixon Branch...phosphorus(per our discussion today) Matt—Here's some info on what I was using for the upper Broad: Broad River USGS gage 02153200(drainage area 1290 sq.mi.) https:Houtlook.office365.com/mail/id/AAQkAGU2YTMOMzll LTc1 NTYtNDAwNy05NzY5LWMyZGZIZGEzYzk1 MAAQAOQpByD7DO%2FJoSw5%2FtKM... 1/4 12/22/21, 12:24 PM Mail-Hill, David A-Outlook DHEC ambient monitoring stations B-042(est.drainage are 1287.5 sq.mi.)and B-044(est.drainage area 1650 sq.mi.). Kings Creek:B-333 No recent gage data here,but there is an old gage:02153600 Let me know if you have any questions/need anything else. Cheers, Matt From:Jeff deBessonet<jdebessonet@water-ec.com> Sent:Friday,August 20,2021 10:50 AM To:Cantrell,Wade<CANTREWM@dhec.sc.gov>;MGoodrich@Water-EC.com;Baumann,Matthew S.<baumanms@dhec.sc.gov> Subject:Re:Dixon Branch...phosphorus(per our discussion today) ***Caution.This is an EXTERNAL email.DO NOT open attachments or click links from unknown senders or unexpected email.*** Thanks for your quick response From iPhone Jeff deBessonet,P.E. Senior Engineer Water Environment Consultants P.O.Box 2221 Mount Pleasant,SC 29465 Cell:803-351-1067(preferred) Office:843-375-9022 www.water-ec.com Specialized Engineering and Permitting Support in the Water Environment From:Cantrell,Wade<CANTREWM@dhec.sc.gov> Sent:Friday,August 20,2021 10:48:59 AM To:Jeff deBessonet<jdebessonet@water-ec.com>;Matt Goodrich<mgoodrich water-ec.com>;Baumann,Matthew S.<baumanms@,dhec.sc.gov> Subject:Re:Dixon Branch...phosphorus(per our discussion today) as discussed from another proposal,calculated increase in P in Broad River after mixing Wade Cantrell 303d,Modeling&TMDL Section Manager Division of Water Quality-Bureau of Water S.C.Dept.of Health&Environmental Control Office:(803)898-3548 Connect:www.scdhec.gov Facebook Twitter From:Jeff deBessonet<jdebessonet@water-ec.com> Sent:Friday,August 20,2021 10:02 AM To:MGoodrich@Water-EC.com<MGoodrichCilWater-EC.com>;Baumann,Matthew S.<baumanmsladhec.sc.gov>;Cantrell,Wade<CANTREWM@dhec.sc.gov> Subject:RE:Dixon Branch...phosphorus(per our discussion today) ***Caution.This is an EXTERNAL email.DO NOT open attachments or click links from unknown senders or unexpected email.*** https:Houtlook.office365.com/mail/id/AAQkAGU2YTMOMzl1 LTc1 NTYtN DAwNy05NzY5LWMyZGZIZG EzYzk 1 MAAQAOQpByD7DO%2FJoSw5%2FtKM... 2/4 12/22/21, 12:24 PM Mail-Hill, David A-Outlook Ok—I'll call in...may have a grandkid making noise in the background(ha) --------------------------------------------- Jeff deBessonet,P.E. Senior Engineer Water Environment Consultants P.O.Box 2221 Mount Pleasant,SC 29465 Cell:803-351-1067 Office:843-375-9022 www.water-ec.com Specialized Engineering and Permitting Support in the Water Environment From:Matt Goodrich<mgoodrich water-ec.com> Sent:Friday,August 20,20219:43 AM To:Baumann,Matthew S.<baumanms@dhec.sc.gov>;Jeff deBessonet<jdebessonet@.water-ec.com>;Cantrell,Wade<CANTREWM@dhec.sc.gov> Subject:RE:Dixon Branch...phosphorus(per our discussion today) That works for me. Thanks Matt ------------------------------------------ Matt Goodrich,P.E. Principal Water Environment Consultants P.O.Box 2221 Mount Pleasant,SC 29465-2221 Office:843-375-9022 ext.2 Cell:843-696-0682 www.water-ec.com Specialized Engineering and Permitting Support in the Water Environment From:Baumann,Matthew S.<baumanms(adhec.sc.gov> Sent:Friday,August 20,20219:06 AM To:Jeff deBessonet<jdebessonet0water-ec.com>;Cantrell,Wade<CANTREWM(Odhec.sc.gov> Cc:Matt Goodrich<mgoodrich water-ec.com> Subject:RE:Dixon Branch...phosphorus(per our discussion today) How does 1030 this morning sound?If so,I can set up a Teams call. From:Jeff deBessonet<jdebessonet@water-ec.com> Sent:Friday,August 20,20219:00 AM To:Cantrell,Wade<CANTREWM@dhec.sc.gov> Cc:MGoodrich(aWater-EC.com;Baumann,Matthew S.<baumanms@ hec.sc.gov> Subject:RE:Dixon Branch...phosphorus(per our discussion today) ***Caution.This is an EXTERNAL email.DO NOT open attachments or click links from unknown senders or unexpected email.*** Monday pm I'm tied up 2-3. --------------------------------------------- Jeff deBessonet,P.E. Senior Engineer Water Environment Consultants P.O.Box 2221 Mount Pleasant,SC 29465 Cell:803-351-1067 Office:843-375-9022 www.water-ec.com Specialized Engineering and Permitting Support in the Water Environment From:Cantrell,Wade<CANTREWM@dhec.sc.gov> Sent:Friday,August 20,20218:56 AM To:Jeff deBessonet<jdebessonet@water-ec.com> Cc:Matt Goodrich<mgoodrich water-ec.com>;Baumann,Matthew S.<baumanms@.dhec.sc.gov> Subject:Re:Dixon Branch...phosphorus(per our discussion today) Jeff- Are you guys available to talk briefly this morning or Monday afternoon? Some further thoughts. Thanks, Wade Wade Cantrell 303d,Modeling&TMDL Section Manager https:Houtlook.office365.com/mail/id/AAQkAGU2YTMOMzl1 LTc1 NTYtNDAwNy05NzY5LWMyZGZIZGEzYzk1 MAAQAOQpByD7DO%2FJoSw5%2FtKM... 3/4 12/22/21, 12:24 PM Mail-Hill, David A-Outlook Division of Water Quality-Bureau of Water S.C.Dept.of Health&Environmental Control Office:(803)898-3548 Connect:www.scdhec.gov Facebook Twitter 0 From:Jeff deBessonet<jdebessonet@water-ec.com> Sent:Wednesday,August 18,2021 3:53 PM To:Cantrell,Wade<CANTREWM@dhec.sc.gov> Cc:MGoodrich@Water-EC.com<MGood rich @Water-EC.com> Subject:Dixon Branch...phosphorus(per our discussion today) ***Caution.This is an EXTERNAL email.DO NOT open attachments or click links from unknown senders or unexpected email.*** Wade:Talked to Joe and the PER work he is doing. He hopes to finish right after labor day—so an answer around then will allow him to confirm that his design will work(e.g.,1 mg/1). He will forward the PER to his client at that point. Make sense? --------------------------------------------- Jeff deBessonet,P.E. Senior Engineer Water Environment Consultants P.O.Box 2221 Mount Pleasant,SC 29465 Cell:803-351-1067 Office:843-37S-9022 www.water-ec.com Specialized Engineering and Permitting Support in the Water Environment https:Houtlook.office365.com/mail/id/AAQkAGU2YTMOMzll LTc1 NTYtNDAwNy05NzY5LWMyZGZIZGEzYzk1 MAAQAOQpByD7DO%2FJoSw5%2FtKM... 4/4 DocuSign Envelope ID:9686938F-2AB0-4656-BAD5-9E5CD43228FF s ROY COOPER L- I p Governor ` 2 DIONNE DELLFGATTI I_v* „ Secretary S.DANIEL SMITH NORTH CAROLINA Director Environmental Quality January 7, 2022 Jeff deBessonet, P.E. Water Environment Consultants PO Box 2221 Mount Pleasant, South Carolina 29465 Subject: Speculative Effluent Limits City of Kings Mountain Cleveland County Broad River Basin Dear Mr. deBessonet: This letter provides speculative effluent limits for a new WWTP serving the City of Kings Mountain located on Dixon Branch with proposed flows of 4.0 and 6.0 MGD. A second location for the discharge was also considered for Kings Creek. These speculative limits replace those dated July 13, 2021 to incorporate total phosphorus limits recommended by the South Carolina Department of Health and Environmental Control. Please recognize that speculative limits may change based on future water quality initiatives, and it is highly recommended that the applicant verify the speculative limits with the Division's NPDES Unit prior to any engineering design work. Receiving Streams. Dixon Branch is located within the Broad River Basin. Dixon Branch has a stream classification of C, and waters with this classification have a best usage for aquatic life propagation and maintenance of biological integrity, wildlife, secondary recreation, and agriculture. Dixon Branch has a summer 7Q10 flow of 0.27 cfs, a winter 7Q10 flow of 0.49 cfs, a 30Q2 flow of 0.62 cfs, and an annual average flow of 1.58 cfs. Kings Creek is currently listed as an impaired waterbody on the 2018 North Carolina 303(d) Impaired Waters List for exceeding benthic criteria. There are no specific permitting strategies or TMDL for Kings Creek, therefore, the Division cannot permit a new discharge that may cause or contribute to an impairment and these speculative limits are for Dixon Branch only. Based upon a review of information available from the North Carolina Natural Heritage Program Online Map Viewer, there are not any Federally Listed threatened or endangered aquatic species identified within a 5-mile radius of the proposed discharge location. If there are any identified threatened/endangered species, it is recommended that the applicant discuss the proposed project with the US Fish and Wildlife Service to determine whether the proposed discharge location might impact such species. Speculative Effluent Limits. Based on Division review of receiving stream conditions and water quality modeling results, speculative limits for a proposed new facility at 4.0 MGD and 6.0 MGD are presented in Table 1. A complete evaluation of these limits and monitoring requirements for DE Q�� North Carolina Department of Environmental Quality I Division of Water Resources _ 512 North Salisbury Street 1 1617 Mail Service Center I Raleigh,North Carolina 27699-1617 NORTH CAROLINA DWIV—d=1 /'� 919.707.9000 DocuSign Envelope ID:9686938F-2AB0-4656-BAD5-9E5CD43228FF metals and other toxicants, as well as potential instream monitoring requirements, will be addressed upon receipt of a formal NPDES permit application. Some features of the speculative limit development include the following: • BOD/NH3 Limits. Assimilative capacity to protect the instream dissolved oxygen standard of 5.0 mg/L was modeled with a NC specific Streeter-Phelps model. NH3 limits are the stricter of that needed to protect instream DO and NH3 toxicity. Please note that this proposed WWTP will have an interacting discharge with the Kings Mountain Travel Plaza (NC0032867) and the combined discharges will use all available assimilative capacity for NH3 toxicity in the stream. The Division will expect connection of the Travel Plaza to the new WWTP to be evaluated in the EAA requirements discussed below. The resultant limits are considered technologically feasible. • Nutrients. To protect downstream uses, the South Carolina Department of Health and Environmental Control recommends that total phosphorus be limited to 1.0 mg/L. TABLE 1. Speculative Limits for City of Kings Mountain proposed new facility. Effluent Characteristic Effluent Limitations Monthly Weekly Daily Average Average Maximum Flow 4.0/6.0 MGD BOD5 5.0 mg/L 7.5 mg/L NH3 as N (Apr.-Oct.) 1.0 mg/L 3.0 mg/L NH3 as N (Nov. -Mar.) 1.8 mg/L 5.7 mg/L Dissolved Oxygen 6.0 mg/L (minimum daily average) Total Phosphorus 1.0 mg/L Monitor& Report (mg/1) TSS 30 mg/L 45 mg/L TRC 17 a /1 Fecal coliform(geometric 200/100 ml 400/100 ml mean) Chronic Toxicity Pass/Fail 90% (Quarterly test) Engineering Alternatives Analysis (EAA). Please note that the Division cannot guarantee that an NPDES permit for a new or expanding discharge will be issued with these speculative limits. Final decisions can only be made after the Division receives and evaluates a formal permit application for the new/expanded discharge. In accordance with North Carolina Administrative Code 15A NCAC 2H.0105(c), the most environmentally sound alternative should be selected from all reasonably cost-effective options. Therefore, as a component of all NPDES permit applications for new or expanding flow, a detailed engineering alternatives analysis (EAA) must be prepared. The EAA must justify requested flows and provide an analysis of potential wastewater treatment alternatives. EAA guidance can be found at: State Environmental Policy Act (SEPA) EA/EIS Requirements. A SEPA EA/EIS document may be required for projects that: 1) involve $10 Million or more of state funds; or 2) will significantly and permanently impact 10 or more acres of public lands. Please check with the Page 2 of 3 DocuSign Envelope ID:9686938F-2AB0-4656-BAD5-9E5CD43228FF DWR SEPA coordinator (David Wainwright, 919-707-9045) as to whether your project requires SEPA review. For projects that are subject to SEPA,the EAA requirements discussed above will need to be folded into the SEPA document. Additionally, if subject to SEPA, the NPDES Unit will not process an NPDES permit application for a new/expanding discharge until the Division has approved the SEPA document and sent a Finding of No Significant Impact(FONSI) to the State Clearinghouse for review and comment. Should you have any questions about these speculative limits or NPDES permitting requirements, please feel free to contact David Hill at david.hillkncdenr.gov or (919) 707- 3612. Respectfully, Michael Montebello Supervisor,NPDES Municipal Permitting Unit Electronic Copy: NC WRC, West Piedmont Coordinator, Olivia.munzer@ncwildlife.org US Fish and Wildlife Service, sara ward@fws.gov /W Office/Mooresville DWRater Quality Regional Oce/Mooresville DWR/Basinwide Planning DWR/NPDES Server>Specs SCDHEC Wade Cantrell, cantrewm@dhec.sc.gov City of Kings Mountain,rickyd@cityofkm.com Page 3 of 3 B3J CONSULTING AENGINEERS, P.A. March 3,2023 Mr.Nick Coco,P.E. NCDEQ Division of Water Resources 512 North Salisbury Street Raleigh,NC,27604 RE: NCO090131 Mill Creek WWTP Additional Information Request Project South Mill Creek WWTP City of Kings Mountain MBD Project No.321010/300 Dear Mr. Coco: We appreciate the email that we received from you and the continuing discussion on the items required on the EAA. We have addressed your first two comments below. We are currently requesting confirmation letters from the Town of Grover and the Travel Lodge on their desire to rescind their existing NPDES permit. The Town of Grover is a biweekly participant in our project meetings and is actively looking forward to closing out the wastewater treatment plant. As your comments state,the chamber at the end of the SBR basins is in fact referred to as a surge tank.The SBR's normal operation includes a treatment cycle and then the basin discharges the water that has accumulated during the cycle(typically around 3.5 hours).The clarified effluent is decanted at a very high rate of flow and the surge tank is used to store the decanted flow. The outlet of the surge tank includes a flow meter and a control valve,as well as a level indicator inside the surge tank itself.The operation of the control valve is based on maintaining flow through the plant at all times to keep the UV bulbs in operation,but also controlling the flow through the filters to eliminate any upsets due to surges.The level indicator in the basin allows for programming to increase the flow as needed to ensure that the surge tank does not overflow at any time. The wastewater treatment plant design does incorporate UV disinfection following the tertiary filtration system.The filters will reduce total suspended solids(TSS)to an acceptable level for the operation of the UV system prior to discharge to Dixon Branch. We appreciate your comments.We will provide the letters from the two entities early next week.If you have any additional comments or questions,please contact this office. Sincerely, Vkt-0-A- Joseph W.McGougan,P.E. President cc:Joel E.Wood,P.E. MBD Consulting Engineers,P.A. 911 Norman Alley Conway,SC 29526 843.488.0124 jdebessonet@water-ec.com From: Weaver, John C <jcweaver@usgs.gov> Sent: Monday,August 24, 2020 10:02 AM To: jdebessonet@water-ec.com Cc: Fine, Jason M; Albertin, Klaus P; Weaver, John C Subject: FW: Response from USGS concerning...Re: Low flow prediction for Dixon Branch and Kings Creek in Cleveland County, North Carolina Importance: High Mr. deBassonet, As I still have an email thread flagged on my laptop following your recent inquiries about low-flow characteristics for Dixon Branch and Kings Creek near Kings Mountain in southeastern Cleveland County, I am forwarding an email from March 2018 in which I provided estimated low-flow discharges for these two streams in response to a separate low-flow request for this information. After considering the map image you included in your first email (July 7), 1 had thoughts recollecting a previous but similar low-flow request for these two streams. Forwarded below is the USGS response to the 2018 low-flow request for Dixon Branch and Kings Creek. Your point of interest on Dixon Branch (1.31 sgmi) is identical to that in the 2018 request. However,your point of interest on Kings Creek (9.85 sgmi) is downstream from the 2018 point of interest for Kings Creek(8.86 sgmi). As the response to this request was completed in 2018,the information (low-flow yields, cfsm) used for this request would still be the same that would be used to complete a response to your request. Therefore, please give consideration to the forwarded email as being similarly applicable as a response to your low-flow request for these two streams. Please let me know of questions or concerns. Hope this information is helpful. Thank you. Curtis Weaver ]. Curtis Weaver, Hydrologist, PE Email; icweaven'Ousas.aov USGS South Atlantic Water Science Center Online:httvs://www.usas.aov/centers/sa-water North Carolina -South Carolina -Georgia 3916 Sunset Ridge Road Raleigh, NC 27607 Phone: (919)571-4043 // Fax: (919)571-4041 From:Weaver,John C<jcweaver@usgs.gov> Sent:Tuesday, March 6, 2018 8:15 AM To:W Ron Haynes<WRHaynes_PE@msn.com> Cc: kingsmountain85@gmail.com; corey.basinger@ncdenr.gov; nickh@cityofkm.com; rickyd@cityofkm.com; 1 donnie.spencer@cityofkm.com; Weaver,John C<jcweaver@usgs.gov> Subject: Response from USGS concerning...Re: Low flow prediction for Dixon Branch and Kings Creek in Cleveland County, North Carolina Importance: High Mr. Haynes, In response to your inquiry about the low-flow characteristics for Dixon Branch and Kings Creek in the vicinity of Kings Mountain in southeastern Cleveland County, the following information is provided: A check of the low-flow files here at the USGS South Atlantic Water Science Center(Raleigh office)indicates a previous low- flow determination at the specific point of interest on Dixon Branch identified by the Iat/long coordinates (35.18901, -81.38279) provided via your email dated February 20, 2018. Completed in February 1966, the 7Q10 discharge was estimated based on transfer of low-flow characteristics from nearby index streamflow sites. The low-flow files also indicate previous low-flow determinations for upstream and downstream locations on Kings Creek in vicinity of the point of interest identified by the lat/long coordinates (35.18659, -81.36751) provided in your February 20 email. Completed in July 1986, the 7Q10 discharges were likewise estimated based on transfer of flow characteristics from nearby index sites. No USGS discharge records are likewise known to exist for the points of interest. In the absence of site-specific discharge records sufficient for a low-flow analysis, estimates of low-flow characteristics at ungaged locations are determined by assessing a range in the low-flow yields (expressed as flow per square mile drainage area, of cfsm)at nearby sites where such estimates have previously been determined. A basin delineation completed using the online USGS StreamStats application for North Carolina (http://water.usgs.gov/osw/streamstats/north carolina.html) indicates the drainage area for the point of interest on Dixon Branch (lat/long 35.18901, -81.38279) is 1.31 sgmi. A basin delineation completed using the online USGS StreamStats application for North Carolina (http://water.usgs.gov/osw/streamstats/north carolina.html) indicates the drainage area for the point of interest on Kings Creek (lat/long 35.18659, -81.36751) is 8.86 sgmi. For streams in Cleveland County, low-flow characteristics published by the USGS are provided in the following reports: (1)The first is a statewide report completed in the early 1990's. It is USGS Water-Supply Paper 2403, "Low-flow characteristics of streams in North Carolina" (Giese and Mason, 1993). An online version of the report is available at http://pubs.usgs.gov/wsp/2403/report.pdf. The report provides the low-flow characteristics (based on data through 1988)via regional relations and at-site values for sites with drainage basins between 1 and 400 sgmi and not considered or known to be affected by regulation and/or diversions. (2)The second is a statewide report published in March 2015. It is USGS Scientific Investigations Report 2015-5001, "Low-flow characteristics and flow-duration statistics for selected USGS continuous-record streamgaging stations in North Carolina through 2012" (Weaver, 2015). The report is available online at http://pubs.us-gs.gov/sir/2015/5001/. The report provides updated low- flow characteristics and flow-duration statistics for 266 active (as of 2012 water year)and discontinued streamgages across the state where a minimum of 10 climatic years discharge records were available for flow analyses. Inspection of the first report indicates the presence of four(4) nearby selected USGS partial-record sites in general vicinity of the points of interest where low-flow characteristics were published. Among these 4 sites, the low-flow discharge yields for the indicated flow statistics are as follows: Annual 7Q10 low-flow yields=_>from 0.13 to 0.38 cfsm(average about 0.21 cfsm) Annual 30Q2 low-flow yields=_>from 0.38 to 0.68 cfsm(average about 0.49 cfsm) Winter 7Q10 low-flow yields=_>from 0.26 to 0.58 cfsm(average about 0.39 cfsm) Average annual discharge yields==>from 1.2 to 1.3 cfsm(average about 1.25 cfsm) Application of the above range in yields to the drainage area (1.31 sgmi)for the point of interest on Dixon Branch results in the following estimated low-flow discharges: 2 Annual 7Q10 discharges=_>from 0.17 to 0.5 cfs(average about 0.3 cfs) Annual 30Q2 discharges=_>from 0.5 to 0.9 cfs(average about 0.65 cfs) Winter 7Q10 discharges=_>from 0.34 to 0.75 cfs(average about 0.5 cfs) Average annual discharge==>from 1.6 to 1.7 cfs(average about 1.65 cfs) Application of the above range in yields to the drainage area (8.86 sgmi)for the point of interest on Kings Creek results in the following estimated low-flow discharges: Annual 7Q10 discharges=_>from about 1.2 to 3.4 cfs(average about 1.9 cfs) Annual 30Q2 discharges=_>from 3.4 to 6.0 cfs(average about 4.3 cfs) Winter 7Q10 discharges=_>from 2.3 to about 5.1 cfs(average about 3.4 cfs) Average annual discharge==>from 10.6 to 11.5 cfs(average about 11.1 cfs) Please note the estimated flows are provided in units of cubic feet per second(cfs). Please understand the information provided in this message is based on a preliminary assessment and considered provisional, subject to revision pending further analyses. Hope this information is helpful. Thank you. Curtis Weaver J. Curtis Weaver, Hydrologist, PE Email: icweaver(cbusas.aov USGS South Atlantic Water Science Center Online:https://www.usgs.gov/centers/sa-water North Carolina -South Carolina -Georgia 3916 Sunset Ridge Road Raleigh, NC 27607 Phone: (919)571-4043 // Fax: (919)571-4041 On Tue, Feb 20, 2018 at 3:18 PM, W Ron Haynes<WRHaynes PE@msn.com>wrote: Thank you for adding us to your schedule Ron Haynes 828/962-7733 From: Weaver,John <jcweaver@uss. ov> Sent:Tuesday, February 20, 2018 2:20 PM To: W Ron Haynes Cc: corey.basinger@ncdenr.gov;Jeanne Robbins;John C Weaver Subject: Re: Low flow prediction for Dixon Branch and Kings Creek in Cleveland County, North Carolina Mr. Haynes, 3 We have received your request for streamflow statistics and anticipate being able to provide a response within the next two months. Please feel free to follow up in April regarding the status of your request. Thank you. Curtis Weaver J. Curtis Weaver, Hydrologist, PE Email: icweaver(cbusas.gov USGS South Atlantic Water Science Center Online:httns://www.usgs.gov/centers/sa-water North Carolina -South Carolina -Georgia 3916 Sunset Ridge Road Raleigh, NC 27607 Phone: (919)571-4043 // Fax: (919)571-4041 On Tue, Feb 20, 2018 at 12:12 PM, W Ron Haynes <WRHaynes PE@msn.com>wrote: This request for winter and summer 7Q10 data for two locations on streams near Kings Mountain, NC is to support planning for relocation and/or establishing a new outfalls for the City of Kings Mountain and Kings Mountain Travel Plaza, an NPDES permittee. Dixon Branch at Lat. Long. 3 5 . 1 8 9 0 1 , - 8 1 . 3 8 2 7 9 Kings Creek at Lat. Long. 3 5 . 1 8 6 5 9 , - 8 1 . 3 6 7 5 1 Thanks for the service you provided now in the past. If you need additional information please let me know. Ron Haynes 828/962-7733 4 1 N S I G N I S �l PARTNERS March 8, 2023 Mr. Joel Wood 104 N. Dilling Street Kings Mountain, NC 28086 RE: Wastewater Plant Decommissioning To Whom it May Concern: MLNC Acquisition, LLC agrees to the closing and decommissioning of the wastewater treatment plant as part of Project South located at 400 Dixon School Road, Kings Mountain, NC 28086. �incer I , Insignis Partners Paul Sparks Managing Partner ROVER- �sss H CAR TOWN OF GROVER 207 Mulberry Road PO Box 189 Grover, North Carolina 28073 704-937-9986 Fax 704-937-9377 March 7, 2023 Mr.Joel Wood 104 N. Dilling Street Kings Mountain, North Carolina 28086 RE: Town of Grover Wastewater Plant Decommissioning To Whom it May Concern: The Town of Grover agrees to the closing and decommissioning of the Town's wastewater treatment plant as part of Project South. Sincerely TOWN OF GROVER Mark McDaniel Public Works Director