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Home My WebLink AboutNC0074772_Permit Modification_20180510Water Resources ENVIRONMENTAL OVALITY May 10, 2018 Shannon V. Becker, President AQUA North Carolina, Inc. 202 MacKenan Court Cary, North Carolina 27511 ROY COOPER Govemor MICHAEL S. REGAN Seuvinq LINDA CULPEPPER brterim Director Subject: Correction to Permit Modification Issued April 12, 2018 NPDES Permit NCO074772 Diamond Head Subdivision WWTP, Grade WW-2 799 Williamson Road, Mooresville Iredell County Dear Mr. Becker: NPDES Staff met with representatives of AQUA on May 4, 2018. At that meeting, AQUA submitted new information not in DWR records; data included a scale drawing and section of the subject WWTP's discharge line. The drawing shows the discharge line extending out into Lake Norman, and descending vertically approximately 35 feet to terminate two feet off the lake bottom (lake elevations establish Nov1986). This drawing describes a "deflector plate" fitted at end -of -pipe, Outfall 001. DWR has no record of the deflector plate or modeling conducted to establish a dilution credit. [owner at installation, Mid -South Water Systems Inc. per ATC dated 22Aug1994 (?)]. Based on this new information, the Division has decided to extend the limit -compliance period to give the Permittee sufficient time to evaluate a dilution factor and/or comply with the permit limits. The compliance deadline is hereby extended to include Total Chloride, Total Fluoride, Total Copper, and Total Zinc; compliance due by the end of the permit cycle (April 1, 2020). Compliance is also extended to WET -testing as Monitoring Only till April 1, 2020. After further modeling and analysis by the Permittee, the Division may consider the "deflector plate" to function as an "effluent diffuser." If dilution is proposed, AQUA shall submit appropriate modeling (for this or alternate diffuser device) for DWR approval, prior to implementation [see Special Condition A. (5.)]. If any parts, measurement frequencies, or sampling requirements contained in this permit are unacceptable, you have the right to an adjudicatory hearing, upon written request submitted within thirty (30) days after receiving this letter. Your request must take the form of a written petition conforming to Chapter 150B of the North Carolina General Statutes, and you must file it with the State of North Carolina I Environmental Quality � Water Resources 1611 Mail service Center I Raleigh, North Carolina 27699-1611 919 707 9000 Shannon V. Becker AQUA Diamond Head W WTP, NC0074772, May 10, 2018 Page 2 office of Administrative Hearings, 6714 Mail Service Center, Raleigh, North Carolina 27699-6714. Unless such a demand is made, this permit shall be final and binding. This permit is not transferable except after notifying the Division of Water Resources. The Division may require permit modification, or revocation and re -issuance. Please note that this permit does not affect your legal obligation to obtain other permits required by the Division of Water Resources, the Division of Land Resources, the Coastal Area Management Act, or other federal or local governments. If you have questions, or if we can further assist you, please contact Joe Corporon at [ioe.corporon ncdem.gov] or call his direct line (919) 807-6394. ctfully, 4 Linda Culpepper Enclosure: NPDES Permit NCO074772 (modification corrections, change -pages 1 thru 9) he: Central Files NPDES Program Files MRO/SWPS, Corey Basinger, Supervisor ec: MRO/SWPS, Corey Basinger, Supervisor OCU, Maureen Kinney ATB, Susan Meadows, Cindy Moore AQUA, Amanda Owens [aaownes@aquaamerica.com] AQUA, Joe Pearce Urpearce@aquaamerica.com] DWR/Public Water Supply; [clintion.cook@ncdenr.gov] Permit NCO074772 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY DIVISION OF WATER RESOURCES PERMIT TO DISCHARGE WASTEWATER UNDER THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) In compliance with the provisions of North Carolina General Statute 143-215.1, other lawful standards and regulations promulgated and adopted by the North Carolina Environmental Management Commission, and the Federal Water Pollution Control Act, as amended, AQUA North Carolina, Inc. is hereby authorized to discharge wastewater from a facility located at the Diamond Head WWTP 799 Williamson Road, Mooresville Iredell County to receiving waters designated as Lake Norman (Reeds Creek Arm) in the Catawba River Basin in accordance with effluent limitations, monitoring requirements, and other conditions set forth in Parts I, II, III and IV hereof. This permit modification (MOD) shall become effective June 1, 2018. This permit and authorization to discharge shall expire at midnight on March 31, 2020. Signed this day May 1 O, 2018. a Culpepper, Interim Dir Division of Water Resources By Authority of the Environmental Management Commission Page 1 of 9 Permit NCO074772 SUPPLEMENT TO PERMIT COVER SHEET All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby revoked. As of this permit issuance, any previously issued permit bearing this number is no longer effective. Therefore, the exclusive authority to operate and discharge from this facility arises under the permit conditions, requirements, terms, and provisions included herein. AQUA North Carolina, Inc. is hereby authorized to: 1. continue to operate an existing 0.0731 MGD wastewater treatment system utilizing the following components: • influent includes trucked -in filter backwash from potable -water treatment [ion - exchange technology] from Subdivision water wells • influent bar screen • V-notch weir • flow -equalization tank • duel (2) aeration basins • dual (2) clarifiers • aerated sludge holding tank • tertiary filters • tablet chlorination and dechlorination • post aeration • flow recorder • effluent pump station • standby power generator these facilities located at the Diamond Head WWTP, 799 Williamson Road, near Mooresville, Iredell County; and 2. discharge from said treatment works via Outfall 001, located on the attached map, into Lake Norman (Reeds Creek Arm), stream index 11-(75), a waterbody currently classified WS-IV; B; CA within subbasin 03-08-32 [HUC: 03050101 ] of the Catawba River Basin; and 3. after receiving an Authorization to Construct (ATC) permit from the Division to expand flow (not to exceed 0.100 MGD); and after submitting to the Division an Engineers Certification form documenting that upgrades were completed in accord with this permit and the ATC, then 4. discharge from said treatment works via Outfall 001, located on the attached map, into Lake Norman (Reeds Creek Arm), stream index 11-(75), a waterbody currently classified WS-IV; B; CA within subbasin 03-08-32 [HUC: 03050101 ] of the Catawba River Basin. Page 2 of 9 Permit NCO074772 0A A. (L) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS [ 15A NCAC 02B .0400 et seq., 02B .0500 et seq.] During the period beginning on the effective date of the permit and lasting until expansion above 0.0731 MGD, [see page 2 of 8] the Permittee is authorized to discharge from Outfall 001. Such discharges shall be limited, monitored and reported 1 by the Permittee as specified below: EFF�.;UENT CHARACTERISTYCS - LIMIT_ S MUNITORINstE_ UIREMENTS . { Daily r Measiireme j� ` , Sample Sample - .2. .toptlily [Parameter Codes] ,., Aveaxirage Mmttm Fr `uenc'pe � .- - - - Location 0.0731 MGD Flow 50050 0.100 MGD 3 Continuous Recording I or E Total Residual Chlorine 4 50060 28 µg/L 2/Week Grab E BOD, 5 day (20°C) C0310 15.0 mg/L 22.5 mg/L Weekly Composite E Total Suspended Solids C0530 30.0 mg/L 45.0 mg/L Weekly Composite E Ammonia (NH3 as N) C0610 4.0 mg/L 20.0 mg/L Weekly Composite E Dissolved Oxygen 00300 Daily Average > 5.0 mg/L Weekly Grab E pH 00400 Not < 6.0 or > 9.0 s. u. Weekly Grab E Fecal Coliform (geometric mean) 31616 200/100 mL 400/100 mL Weekly Grab E Temperature (°C) 00010 Weekly Grab E Total Hardness — as [CaCO3 or +M 00900 Quarterly Composite E (Ca m Total Hardness — as [CaCO3 or 00900 Quarterly Grab U (Ca +M m Total Copper 01042 7.88 µg/L, 5 10.47 µg/L 5 Quarterly Composite E Total Fluoride 00951 1,800 µg/L 516 1,800 µg/L 59 6 Quarterly Composite E Total Chloride 00940 230 mg/L 5 250 mg/L 5 Quarterly Composite E Total Zinc 01092 125.7 µg/L 5 125.7 µg/L 5 Quarterly Composite E Total Nitrogen (mg/L) 7 C0600 Monitor & Report Quarterly Composite E 02+ NO3 + Total Phosphorus (mg/L) C0665 Monitor & Report Quarterly Composite E Combined radium-226 and radium-228 (pCi/L) 89 9 11503 5 pCi/L (annual ave.) Quarterly Composite E Alpha emitters, excluding radon and uranium (pCi/L) 8' 9 82077 15 pCi/L (annual ave.) Quarterly Composite E Beta emitters, excluding K-40 and other naturally occurring 03520 50 pCi/L (annual ave.) Quarterly Composite E radionuclides (pCi/L) 8 9 Tritium (pCi/L) 8' 9 82126 20,000 pCi/L (annual ave.) Quarterly Composite E Strontium-90 (pCi/L) g' 9 13501 8 pCi/L (annual ave.) Quarterly Composite E Uranium (µg/L) 8' 9' 10 22708 30 µg//L (weekly ave.) 9 Quarterly Composite E Whole Effluent Toxicity (WET) 11 TGP3B Quarterly Grab E See Footnotes, Page 4 Page 3 of 9 Permit NCO074772 Table A. I.) Footnotes: 1. The Permittee shall submit discharge monitoring reports electronically using the Division's electronic Discharge Monitoring Report System (eDMR) system [see A. (5)]. 2. E = Effluent; I = Influent; U = Upstream 3. Discharge at 0.100 MGD is permitted only after applying for, and receiving the Division's Authorization to Construct (ATC) permit and submitting an Engineers Certification form (see page 2 of 9). 4. The Division shall consider compliant all effluent TRC values reported below 50 µg/L. However, the Permittee shall continue to record and submit all values reported by a North Carolina -certified test method (including field certified), even if these values fall below 50 jig/L. 5. Compliance to this limit begins on April 1, 2020, approximately 23 months from the permit effective date. 6. Limit applies only if fluoride is added by the Permittee. 7. For a given wastewater sample, TN = TKN + (NO2-N + NO3 I), where TN is Total Nitrogen and TKN is Total Kjeldahl Nitrogen, and (NO2-N + NO3 N) is Nitrite/Nitrate Nitrogen. 8. If the quarterly value exceeds 4 times the annual average limit, then (a) the sampling frequency shall increase to Monthly and (b) a written notification shall be sent to the Water Quality Permitting Section and the Division's Mooresville Regional Office. 9. This sample shall be taken promptly within 72 to 80 hours after each introduction of offsite wastewater into the equalization tank. If an introduction of offsite wastewater does not occur within a given calendar quarter, a sample shall be taken of the effluent and noted in the DMR and eDMR Comments as "No introduction of offsite wastewater occurred during this quarter." 10. Because Uranium is limited as a Weekly Average, [adopted federal criteria 40CFR 141.26], a quarterly value may be determined from one (1) quarterly sample, or by averaging multiple samples taken within a restricted time -period, not -to -exceed a calendar week [Sunday thru Saturday]. 11. WET Testing, Chronic; Quarterly using Ceriodaphnia dubia, limited [TGP3B]; effluent concentration at 90% during the months of January, April, July and October [See A. (2.)]. Compliance to WET testing begins on April 1, 2020, or upon DWR's approval of the Permittee's dilution study results [see Special Condition A. (5.)]. Conditions: 1. The Permittee shall discharge no floating solids or foam visible in other than trace amounts. 2. Effluent samples shall accurately represent the physical and chemical character of the discharge. Page 4 of 9 Permit NCO074772 A. (2.) CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY) [I 5A NCAC 02B.0200, et. seq.] The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant mortality to Ceriodaphnia dubia at an effluent concentration of 90 %. The permit holder shall perform at a minimum, quarterly monitoring using test procedures outlined in the "North Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure" (revised December 2010 or subsequent versions), or "North Carolina Phase H Chronic Whole Effluent Toxicity Test Procedure" (revised- December 2010 or subsequent versions). Tests will be performed during the months of January, April, July and October. These months signify the first month of each three-month toxicity testing quarter assigned to the facility. Effluent sampling for this testing must be obtained during representative effluent discharge and shall be performed at the NPDES-permitted final effluent discharge below all treatment processes. If the test procedure, performed as the first test of any single quarter, results in a failure or ChV below the permit limit, then multiple -concentration testing shall be performed at a minimum, in each of the two following months, as described in "North Carolina Phase H Chronic Whole Effluent Toxicity Test Procedure" (revised -December 2010), or subsequent versions. All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge Monitoring Form (MR-1) for the months in which tests were performed, using the parameter code TGP3B for the pass/fail results and THP3B for the Chronic Value. Additionally, DWR Form AT-3 (original) is to be sent to the following address: Attention: North Carolina Division of Water Resources Water Sciences Section/Aquatic Toxicology Branch 1621 Mail Service Center Raleigh, NC 27699-1621 Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30 days after the end of the reporting period for which the report is made. Test data shall be complete, accurate, include all supporting chemical/physical measurements and all concentration/response data, and be certified by laboratory supervisor and ORC or approved designate signature. Total residual chlorine of the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of the waste stream. Should there be no discharge of flow from the facility during a month in which toxicity monitoring is required, the permittee will complete the information located at the top of the aquatic toxicity (AT) test form indicating the facility name, permit number, pipe number, county, and the month/year of the report with the notation of "No Flow" in the comment area of the form. The report shall be submitted to the Water Sciences Section at the address cited above. Should the permittee fail to monitor during a month in which toxicity monitoring is required, monitoring will be required during the following month. Assessment of toxicity compliance is based on the toxicity testing quarter, which is the three-month time interval that begins on the first day of the month in which toxicity testing is required by this permit and continues until the final day of the third month. Should any test data from this monitoring requirement or tests performed by the North Carolina Division of Water Resources indicate potential impacts to the receiving stream, this permit may be re -opened and modified to include alternate monitoring requirements or limits. NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum control organism survival, minimum control organism reproduction, and appropriate environmental controls, shall constitute an invalid test and will require immediate follow-up testing to be completed no later than the last day of the month following the month of the initial monitoring. Page 5 of 9 Permit NCO074772 A. (3.) SPECIAL CONDITION —Operations [G.S. 143-215.1 C.] (a) Inspect the performance of the plant's disinfection system every weekday and maintain a log of such inspections; and (b) Operate a Supervisory Control and Data Acquisition (SCADA) system at the plant. A. (4.) SPECIAL CONDITION — Spill Notification [G.S. 143-215.1 C.] (a) Contacting Public Health Directors The facility must notify the Iredell and Mecklenburg County Public Health Directors within 12 hours of first knowledge by the owner/operator of any discharge of untreated wastewater to waters of the State or a discharge from the wastewater treatment plant that has not received adequate disinfection due to a malfunctioning treatment unit. The County Public Health Directors can be contacted using the following information: Iredell County Health Director 318 Turnersburg Highway Statesville, NC 28625 704-878-5300 (b) Public Notification Mecklenburg County Health Director 249 Billingsley Road Charlotte, NC 28211 704-3364700 The facility must notify the public of untreated wastewater spills. Wastewater facility owners or operators must issue a press release after a discharge to surface waters of 1,000 gallons within 24 hours of first knowledge of the spill by the owner/operator. The press release must be issued to "all electronic and print news media outlets that provide general coverage in the county where the discharge occurred." A copy of the press release must be maintained for one year by the owner/operator. This press release is required in addition to the permit requirement of contacting the North Carolina Division of Water Resources (DWR). If a discharge of 15,000 gallons or more reaches surface water, a public notice is required in addition to the press release. The public notice must be placed in a newspaper having general circulation in the County in which the discharge occurred and the county immediately downstream. The owner or operator shall publish the notice within 10 days after the Secretary has determined the countries that are significantly affected by the discharge and approved the form and content of the notice and the newspaper in which the notice is to be published. At a minimum the notice should be published in a newspaper of general circulation in Iredell and Mecklenburg Counties. If a discharge of 1,000,000 gallons of wastewater or more reaches surface waters, the DWR regional office must be contacted to determine in what additional counties, if any, a public notice must be published. A copy of these public notices and proof of publication must be sent to the DWR within 30 days of publication. The copy should be sent to the following address: Division of Water Resources PERCS Unit 1617 Mail Service Center Raleigh, NC 27699-1617 The minimum content of the notice is the location of the discharge, estimated volume, water body affected and steps taken to prevent future discharges. Page 6 of 9 Permit NCO074772 A. (5.) SPECIAL CONDITION - STUDY TO ESTABLISH DILUTION [G.S. 143-215.1(C)] To establish effluent dilution credit, the Permittee shall submit to DWR a Study Plan and recommendations for dilution modeling. This plan may address the existing end -of -pipe effluent "deflector plate" or other diffuser, as approved by the Division. The Permittee shall submit this plan to: DEQ/NCDWR/NPDES Unit 1617 Mail Service Center, Raleigh, NC 27699 attention Teresa Rodriguez [teresa.rodriguez a@ncdenr.gov]; 919-807-6387 This plan shall recommend steps needed to establish an instream waste concentration (IWC) at the point of discharge. Upon plan approval, the Permittee shall conduct the study, and submit to DWR the results, findings and conclusions. Following approval, the Division may adjust permit limits and monitoring conditions in accord with the revised effluent conditions, as data may warrant. If approved before permit expiration (March 30, 2020), the Division may apply this dilution credit to the permit. A. (6.) ELECTRONIC REPORTING OF DISCHARGE MONITORING REPORTS [G.S. 143-215.1(b)] Federal regulations require electronic submittal of all discharge monitoring reports (DMRs) and program reports. The final NPDES Electronic Reporting Rule was adopted and became effective on December 21, 2015. NOTE: This special condition supplements or supersedes the following sections within Part II of this permit (Standard Conditions for NPDES Permits): • Section B. (11.) • Section D. (2.) • Section D. (6.) • Section E. (5.) Signatory Requirements Reporting Records Retention Monitoring Reports 1. Reporting Requirements [Supersedes Section D. (2.) and Section E. (5.) (a)1 The permittee shall report discharge monitoring data electronically using the NC DWR's Electronic Discharge Monitoring Report (eDMR) internet application. Monitoring results obtained during the previous month(s) shall be summarized for each month and submitted electronically using eDMR. The eDMR system allows permitted facilities to enter monitoring data and submit DMRs electronically using the internet. Until such time that the state's eDMR application is compliant with EPA's Cross -Media Electronic Reporting Regulation (CROMERR), permittees will be required to submit all discharge monitoring data to the state Page 7 of 9 Permit NC0074772 electronically using eDMR and will be required to complete the eDMR submission by printing, signing, and submitting one signed original and a copy of the computer printed eDMR to the following address: NC DEQ / Division of Water Resources / Water Quality Permitting Section ATTENTION: Central Files 1617 Mail Service Center Raleigh, North Carolina 27699-1617 If a permittee is unable to use the eDMR system due to a demonstrated hardship or due to the facility being physically located in an area where less than 10 percent of the households have broadband access, then a temporary waiver from the NPDES electronic reporting requirements may be granted and discharge monitoring data may be submitted on paper DMR forms (MR 1, 1.1, 2, 3) or alternative forms approved by the Director. Duplicate signed copies shall be submitted to the mailing address above. See "How to Request a Waiver from Electronic Reporting" section below. Regardless of the submission method, the first DMR is due on the last day of the month following the issuance of the permit or in the case of a new facility, on the last day of the month following the commencement of discharge. Starting on December 21, 2020, the permittee must electronically report the following compliance monitoring data and reports, when applicable: Sewer Overflow/Bypass Event Reports; Pretreatment Program Annual Reports; and Clean Water Act (CWA) Section 316(b) Annual Reports. The permittee may seek an electronic reporting waiver from the Division (see "How to Request a Waiver from Electronic Reporting" section below). 2. Electronic Submissions In accordance with 40 CFR 122.410)(9), the permittee must identify the initial recipient at the time of each electronic submission. The permittee should use the EPA's website resources to identify the initial recipient for the electronic submission. Initial recipient of electronic NPDES information from NPDES-regulated facilities means the entity (EPA or the state authorized by EPA to implement the NPDES program) that is the designated entity for receiving electronic NPDES data [see 40 CFR 127.2(b)]. EPA plans to establish a website that will also link to the appropriate electronic reporting tool for each type of electronic submission and for each state. Instructions on how to access and use the appropriate electronic reporting tool will be available as well. Information on EPA's NPDES Electronic Reporting Rule is found at: h=s://www.federalregister.gov/documents/2015/10/22/2015- 24954/national-pollutant-discharge-elimination-system-npdes-electronic-reporting-rule Electronic submissions must start by the dates listed in the "Reporting Requirements" section above. Page 8 of 9 Permit NC0074772 3. How to Request a Waiver from Electronic Reporting The permittee may seek a temporary electronic reporting waiver from the Division. To obtain an electronic reporting waiver, a permittee must first submit an electronic reporting waiver request to the Division. Requests for temporary electronic reporting waivers must be submitted in writing to the Division for written approval at least sixty (60) days prior to the date the facility would be required under this permit to begin submitting monitoring data and reports. The duration of a temporary waiver shall not exceed 5 years and shall thereupon expire. At such time, monitoring data and reports shall be submitted electronically to the Division unless the permittee re -applies for and is granted a new temporary electronic reporting waiver by the Division. Approved electronic reporting waivers are not transferrable. Only permittees with an approved reporting waiver request may submit monitoring data and reports on paper to the Division for the period that the approved reporting waiver request is effective. Information on eDMR and the application for a temporary electronic reporting waiver are found on the following web page: http://dgg.nc.gov/about/divisions/water-resources/edmr 4. Signatory Requirements [Supplements Section B. (11.) (b) and Supersedes Section B. (11.) (d)l All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part H, Section B. (I 1.)(a) or by a duly authorized representative of that person as described in Part II, Section B. (I 1.)(b). A person, and not a position, must be delegated signatory authority for eDMR reporting purposes. For eDMR submissions, the person signing and submitting the DMR must obtain an eDMR user account and login credentials to access the eDMR system. For more information on North Carolina's eDMR system, registering for eDMR and obtaining an eDMR user account, please visit the following web page: bq://dgg.nc.gov/about/divisions/Water-resources/edmr Certification. Any person submitting an electronic DMR using the state's eDMR system shall make the following certification [40 CFR 122.221. NO OTHER STATEMENTS OF CERTIFICATION WILL BE ACCEPTED: 7 certify, under penalty of law, that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fines and imprisonment for knowing violations. " 5. Records Retention [Supplements Section D. (6.)] The permittee shall retain records of all Discharge Monitoring Reports, including eDMR submissions. These records or copies shall be maintained for a period of at least 3 years from the date of the report. This period may be extended by request of the Director at any time [40 CFR 122.41]. Page 9 of 9 0 Outfa11001 Lat 35' 33' 52" Long 80' 51' 58" (lake discharge) •� WWTP approximate location Williamson Road M F US HWY I-77 550 AQUA North Carolina Diamond Head Subdivision WWTP Facility Location A Receiving Stream: lake Norman [Reeds Creek Branch] not to scale Stream Segment: I l{75) Stream Class: WS-IV: B; CA State Grid/Ound: El5SE/ Mooresville, NC River Basin: Catawba River Sub -Basin: 03.08-32 HUC: 03050101 North] NPDES Permit NCO074772 Iredell Count NCDEQ / DWR / NPDES ADENDUM TO FACT SHEET - NPDES PERMIT MODIFICATION NPDES Permit NCO074772 Joe R. Corporon, L.G., Compliance & Expedited Permitting Unit / 919-807-6394 07May2017 Table 1:-- Facility nfonaaatio - Appheant/FacilityNarne - AQUA North Carolina' Inc. Diamond Head Subdivision WWTP, Class 2 Applicant Address _ 202 Mackenan Court, Cary, NC 27511 Facxly Address 799 Williamson Road, Mooresville Pexmtted.Flow ,(1VIGD) Phase 1: 0.0731 MGD, and Phase 2: 0.100 MGD Type of Waste Discharging 100% domestic < 1 MGD Facility Class WW-2 County Iredell Permit: -Status Renewal Regional Office: MRO = Stream. Characteristics _ Receiving Stream Lake Norman [Reeds Creek Arm] Stream Classification WS-IV; B; CA Stream Segment l l -(75) Drainage basin Catawba Summer 70i0 (cfs) Subbasin 03-08-32 Wintejt 7Q10 (cfs) Use Support Statewide advisory for Hg [HH for fish consumption] 30Q2 (cfs) 303(d) Listed Average Flow (cfs) State Grid E15SE IWC{% o) Phase 4 & 2- Lake discharge USGS Quad Mooresville, NC Facility Summary — This facility is a privately owned minor WWTP (flow <1 MGD) receiving 100% domestic wastewater, plus a proposed uranium -filter generated backwash from ion -exchange (IE) treatment of potable -water. The WWTP's extended -aeration treatment system is currently designed for a maximum capacity of 0.0731 MGD, but the permit is "phased" to allow expansion not to exceed 0.100 MGD. Update: Following AQUA's request to meet and discuss the permit modification, NPDES staff met on 04May2018 with AQUA's Amanda Owens, Manager of Environmental Compliance, supported by Joseph Pearce, PE, CFM. AQUA submitted a new document (not in DWR records); a scale drawing and section of the WWTP's discharge line. The drawing shows the line extending out into Lake Norman, and descending vertically some 35 feet to terminate two feet off the lake bottom (lake elevations establish Nov1986). This drawing describes a "deflector plate" fitted at end -of -pipe, Outfall 001. This new information will be identified as a permit correction. DWR has no record of the deflector plate or modeling conducted to establish a dilution credit. [owner at installation, Mid -South Water Systems Inc. (?) per ATC dated 22Augl994]. The drawing and text were apparently generated at installation (signed and stamped by Land Design). After further modeling and analysis by the Permittee, the Division may consider this "deflector plate" to function as an "effluent diffuser." If dilution is proposed, AQUA shall submit a Modeling Plan (for this or an alternate diffuser device) for DWR approval, prior to implementation. Fact Sheet Addendum for Permit Modification 07May2017 -- NPDES Permit NCO074772 - Page 1 750 940 WILLIAMSON RD. S.R. 1109 TO t-n/ d'EFFLUENT FORDS ,MAIN ; F3.LW DIAMOND HEAD ired by Joe Pearce on May 3, 2018 Notes Norman Catchment Area 1790 square miles zind Head Discharge Catchment Area 10 square miles Norman Average Flow 1370 MGD (Data from 2005 to present) Norman 30Q2 51.7 MGD (Data from 2005 to present) Norman 7010 51.7 MGD (Data from 2005 to present) and Head Discharge Point Average Flow 7.65 MGD (Based on Catchment Area proportionality) and Head Discharge Point 30Q2 0.29 MGD (Based on Catchment Area proportionality) and Head Discharge Point 7Q10 0.29 MGD (Based on Catchment Area proportionality) ondheadPermitted Flow After Expansion 0.1 MGD am Waste Concentration 34.62% 7Q10 and 30Q2 am Waste Concentration 1.3% Average Flow s Draft Permit Proposed mg/I mg/I er 0.00788 Monitoring unless WET issue ide 1.8 5.2 (Note: the well water is not Fluoridated and this limit is unnecessary) Chloride 230 722.0670391 (Note: 250 mgll standard is for WS and based on 30Q2) 0.1257 Monitoring unless WET issue pCi/L pCi/L d Radium 5 383 (Note: Based on Average Flow IWC) 15 1148 (Note: Based on Average Flow IWC) 50 3827 (Note: Based on Average Flow IWC) 20000 1530726 (Note: Based on Average Flow IWC) (ug/1) 30 2296 (Note: Based on Average Flaw IWC) 90% 35% 7010 Basis WaterResources ENVIRONMENTAL QUALITY April 12, 2018 Shannon V. Becker, President AQUA North Carolina, Inc. 202 MacKenan Court Cary, North Carolina 27511 ROY COOPER Governor MICHAEL S. REGAN secreuvy LINDA CULPEPPER Interim Director Subject: Issuance of Permit Modification to Extend Limit Deadline for Total Copper NPDES Permit NCO074772 Diamond Head Subdivision WWTP, Grade WW-2 799 Williamson Road, Mooresville Iredell County Dear Mr. Becker: The Division acknowledges receiving your letter dated February 28, 2018 requesting DWR to extend the limit compliance period to include metals and those parameters potentially radioactive. Please review the attached change -pages [lthru 9] to insure your understanding of the revised limits and monitoring conditions. Modification Changes. In accord with your request of November 27, 2017, we have extended to the end of this permit cycle, the deadline to comply with Total Copper limits. Your compliance to Total Copper limits begins on the April 1, 2020. Until said date, you must comply with all existing parameter limits, except Total Copper. Responding to your request to extend limit compliance period to multiple parameters: Your request lists all the parameters that AQUA has volunteered to introduce to the subject W WTP from a second, separate facility, an ion -exchange (IE) potable water treatment plant (WTP) owned by AQUA. You further request the Division to relax Whole Effluent Toxicity (WET) testing to "Monitor Only" citing DWR's WTP strategy of October 14, 2009. Please be advised that said permitting guidance applies to potable water treatment plants (WTPs) only - not W WTP permitting. Your requests must be denied. This permit modification has gone to Public Notice in accord with the NPDES Program. No public comments were received during this notice period. If any parts, measurement frequencies, or sampling requirements contained in this permit are unacceptable, you have the right to an adjudicatory hearing, upon written request submitted within thirty (30) days after receiving this letter. Your request must take the form of a written petition conforming to Chapter 150B of the North Carolina General Statutes, and you must file it with the State of North Carolina I Envirovenemal Quality I Water Resources 1611 Mail service Center I Raleigh, North Camlirta 27699-1611 919 707 9000 Shannon V. Becker AQUA Diamond Head W WTP, NC0074772, April 5, 2018 Page 2 office of Administrative Hearings, 6714 Mail Service Center, Raleigh, North Carolina 27699-6714. Unless such a demand is made, this permit shall be final and binding. This permit is not transferable except after notifying the Division of Water Resources. The Division may require permit modification, or revocation and re -issuance. Please note that this permit does not affect your legal obligation to obtain other permits required by the Division of Water Resources, the Division of Land Resources, the Coastal Area Management Act, or other federal or local governments. If you have questions, or if we can further assist you, please contact Joe Corporon at [ioe.comoron64ncdenr.¢ov] or call his direct line (919) 807-6394. espe tfully, Linda Culpepper Enclosure: NPDES Permit NC0074772 (modification issuance, change -pages 1 thru 9) hc: Central Files NPDES Program Files MRO/SWPS, Corey Basinger, Supervisor ec: MRO/SWPS, Corey Basinger, Supervisor OCU, Maureen Kinney ATB, Susan Meadows, Cindy Moore AQUA, Laurie Ison [LTIson@aquaamerica.com] DWR/Public Water Supply; [chntion.cook@ncdenr.gov] Permit NCO074772 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY DIVISION OF WATER RESOURCES PERMIT TO DISCHARGE WASTEWATER UNDER THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM DES) In compliance with the provisions of North Carolina General Statute 143-215.1, other lawful standards and regulations promulgated and adopted by the North Carolina Environmental Management Commission, and the Federal Water Pollution Control Act, as amended, AQUA North Carolina, Inc. is hereby authorized to discharge wastewater from a facility located at the Diamond Head WWTP 799 Williamson Road, Mooresville Iredell County to receiving waters designated as Lake Norman (Reeds Creek Arm) in the Catawba River Basin in accordance with effluent limitations, monitoring requirements, and other conditions set forth in Parts I, II, III and IV hereof. This permit modification (MOD) shall become effective May l , 2018. This permit and authorization to discharge shall expire at midnight on March 31, 2020. Signed this day April 12, 2018. a Culpepper, Interim Dir or Division of Water Resources By Authority of the Environmental Management Commission Page 1 of 9 Permit NCO074772 SUPPLEMENT TO PERMIT COVER SHEET All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby revoked. As of this permit issuance, any previously issued permit bearing this number is no longer effective. Therefore, the exclusive authority to operate and discharge from this facility arises under the permit conditions, requirements, terms, and provisions included herein. AQUA North Carolina, Inc. is hereby authorized to: 1. continue to operate an existing 0.0731 MGD wastewater treatment system utilizing the following components: • influent includes trucked -in filter backwash from potable -water treatment [ion - exchange technology] from Subdivision water wells • influent bar screen • V-notch weir • flow -equalization tank • duel (2) aeration basins • dual (2) clarifiers • aerated sludge holding tank • tertiary filters • tablet chlorination and dechlorination • post aeration • flow recorder • effluent pump station • standby power generator these facilities located at the Diamond Head WWTP, 799 Williamson Road, near Mooresville, Iredell County; and 2. discharge from said treatment works via Outfall 001, located on the attached map, into Lake Norman (Reeds Creek Arm), stream index 11-(75), a waterbody currently classified WS-IV; B; CA within subbasin 03-08-32 [HUC: 03050101 ] of the Catawba River Basin; and 3. after receiving an Authorization to Construct (ATC) permit from the Division to expand flow (not to exceed 0.100 MGD); and after submitting to the Division an Engineers Certification form documenting that upgrades were completed in accord with this permit and the ATC, then 4. discharge from said treatment works via Outfall 001, located on the attached map, into Lake Norman (Reeds Creek Arm), stream index 11-(75), a waterbody currently classified WS-IV; B; CA within subbasin 03-08-32 [HUC: 03050101 ] of the Catawba River Basin. Page 2 of 9 Permit NCO074772 Part I A. (L) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS [ 15A NCAC 02B .0400 et seq., 02B -.0500 et seq.] During the period beginning on the effective date of the permit and lasting until expansion above 0.0731 MGD, [see page 2 of 8] the Permittee is authorized to discharge from Outfall 001. Such discharges shall be limited, monitored and reported 1 by the Permittee as specified below: E lai'ICSIMI�S f s� . t r _ bIo+„� •,PNam l wv Na�m�ier^VQ � .. Y {'�'4«,::+..•-... �.«s.. �.-:, _.... s Y.�- ..+i..�' -.: NCQ�OT� ,•iY..ui 7 A e �AiR i3rc.iLiases.j- Dail rsiu�eiment J' s f s . M uMi a r, r *�i-� ,'�A Ne Ba Sq'cf'"c4,t r ~1�' a ° iMAoli S mile ,7 xt� �t- f�A 1� Z Flow 50050 0.0731 MGDContinuous 0.100 MGD 3 Recording I or E Total Residual Chlorine 4 50060 28 µg/L 2/Week Grab E BOD, 5 day (20°C) C0310 15.0 mg/L 22.5 mg/L Weekly Composite E Total Suspended Solids C0530 30.0 mg/L 45.0 mg/L Weekly Composite E Ammonia (NH3 as N) C0610 4.0 mg/L 20.0 mg/L Weekly Composite E Dissolved Oxygen 00300 Daily Average > 5.0 mg/L Weekly Grab E pH 00400 Not < 6.0 or > 9.0 s. u. Weekly Grab E Fecal Coliform (geometric mean) 31616 200/100 mL 400/100 mL Weekly Grab E Temperature (°C) 00010 Weekly Grab E Total Hardness — as [CaCO3 or (Ca + M m 00900 Quarterly Composite E Total Hardness — as [CaCO3 or (Ca +M m 00900 Quarterly Grab U Total Copper 01042 7.88 µg/L 5 10.47 µg/L 5 Quarterly Composite E Total Fluoride 00951 1,800 µg/L 1,800 µg/L Quarterly Composite E Total Chloride 00940 230 mg/L 250 mg/L Quarterly Composite E Total Zinc 01092 125.7 µg/L 125.7 µg/L Quarterly Composite E Total Nitrogen (mg/L) 6 (NO2 + NO3 + C0600 Monitor & Report Quarterly Composite E Total Phosphorus (mg/L) C0665 Monitor & Report Quarterly Composite E Combined radium-226 and radium-228 (pCi/L) 71,8 11503 5 pCi/L (annual ave.) Quarterly Composite E Alpha emitters, excluding radon and uranium (pCi/L) 7, 8 82077 15 pCi/L (annual ave.) Quarterly Composite E Beta emitters, excluding potassium- 40 and other naturally occurring radionuclides (pCi/L) 7' 8 03520 50 pCi/L (annual ave.) Quarterly Composite E Tritium (pCi/L)•7' 8 82126 20,000 pCi/L (annual ave.) Quarterly Composite E Strontium-90 (pCi/L) 7' 8 13501 8 pCi/L (annual ave.) Quarterly Composite E Uranium (µg/L) 79 8, 9 22708 30 µg//L (weekly ave.) 9 Quarterly Composite E Whole Effluent Toxicity (WET)10 TGP3B Quarterly Grab E See Footnotes, Page 4 Page 3 of 9 Permit NC00747 72 Table A. (L) Footnotes: 1. The Permittee shall submit discharge monitoring reports electronically using the Division's electronic Discharge Monitoring Report System (eDMR) system [see A. (5)]. 2. E = Effluent; I = Influent; U = Upstream 3. Discharge at 0.100 MGD is permitted only applying for, and receiving the Division's Authorization to Construct (ATC) permit and submitting Engineers Certification form (see page 2 of 9). 4. The Division shall consider compliant all effluent TRC values reported below 50 jig/L. However, the Permittee shall continue to record and submit all values reported by a North Carolina -certified test method (including field certified), even if these values fall below 50 µg/L. 5. Compliance to this limit begins on April 1, 2020, approximately 23 months from the permit effective date. 6. For a given wastewater sample, TN = TKN + (NO2 N + NO3-N), where TN is Total Nitrogen and TKN is Total Kjeldahl Nitrogen, and (NO2 N + NO3 N) is Nitrite/Nitrate Nitrogen. 7. If the quarterly value exceeds 4 times the annual average limit, then (a) the sampling frequency shall increase to Monthly and (b) a written notification shall be sent to the Water Quality Permitting Section and the Division's Mooresville Regional Office. 8. This sample shall be taken promptly within 72 to 80 hours after each introduction of offsite wastewater into the equalization tank. If an introduction of offsite wastewater does not occur within a given calendar quarter, a sample shall be taken of the effluent and noted in the DMR and eDMR Comments as "No introduction of offsite wastewater occurred during this quarter." 9. Because Uranium is limited as a Weekly Average, [adopted federal criteria 40CFR 141.26], a quarterly value may be determined from one (1) quarterly sample, or by averaging multiple samples taken within a restricted time period, not -to -exceed a calendar week [Sunday thru Saturday]. 10. WET Testing, Chronic; Quarterly using Ceriodaphnia dubia, limited [TGP3B]; effluent concentration at 90% during the months of January, April, July and October [See A. (2.)]. Conditions: 1. The Permittee shall discharge no floating solids or foam visible in other than trace amounts. 2. Effluent samples shall accurately represent the physical and chemical character of the discharge. Page 4 of 9 .t Permit NCO074772 A. (2.) CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY) [I SA NCAC 02B.0200, et. seq.] The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant mortality to Ceriodaphnia dubia at an effluent concentration of 90 %. The permit holder shall perform at a minimum, quarterly monitoring using test procedures outlined in the "North Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure" (revised December 2010 or subsequent versions), or "North Carolina Phase H Chronic Whole Effluent Toxicity Test Procedure" (revised- December 2010 or subsequent versions). Tests will be performed during the months of January, April, July and October. These months signify the first month of each three-month toxicity testing quarter assigned to the facility. Effluent sampling for this testing must be obtained during representative effluent discharge and shall be performed at the NPDES permitted final effluent discharge below all treatment processes. If the test procedure, performed as the first test of any single quarter, results in a failure or ChV below the permit limit, then multiple -concentration testing shall be performed at a minimum, in each of the two following months, as described in "North Carolina Phase H Chronic Whole Effluent Toxicity Test Procedure" (revised -December 2010), or subsequent versions. All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge Monitoring Form (MR-1) for the months in which tests were performed, using the parameter code TGP3B for the pass/fail results and THP3B for the Chronic Value. Additionally, DWR Form AT-3 (original) is to be sent to the following address: Attention: North Carolina Division of Water Resources Water Sciences Section/Aquatic Toxicology Branch 1621 Mail Service Center Raleigh, NC 27699-1621 Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30 days after the end of the reporting period for which the report is made. Test data shall be complete, accurate, include all supporting chemical/physical measurements and all concentration/response data, and be certified by laboratory supervisor and ORC or approved designate signature. Total 'residual chlorine of the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of the waste stream. Should there be no discharge of flow from the facility during a month in which toxicity monitoring is required, the permittee will*complete the information located at the top of the aquatic toxicity (AT) test form indicating the facility name, permit number, pipe number, county, and the month/year of the report with the notation of "No Flow" in the comment area of the form. The report shall be submitted to the Water Sciences Section at the address cited above. Should the permittee fail to monitor during a month in which toxicity monitoring is required, monitoring will be required during the following month. Assessment of toxicity compliance is based on the toxicity testing quarter, which is the three-month time interval that begins on the first day of the month in which toxicity testing is required by this permit and continues until the final day of the third month. Should any test data from this monitoring requirement or tests performed by the North Carolina Division of Water Resources indicate potential impacts to the receiving stream, this permit may be re -opened and modified to include alternate monitoring requirements or limits. NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum control organism survival, minimum control organism reproduction, and appropriate environmental controls, shall constitute an invalid test and will require immediate follow-up testing to be completed no later than the last day of the month following the month of the initial monitoring. Page 5 of 9 Permit NC0074772 A. (3.) SPECIAL CONDITION —Operations [G.S. 143-215.1C.] (a) Inspect the performance of the plant's disinfection system every weekday and maintain a log of such inspections; and (b) Operate a Supervisory Control and Data Acquisition (SCADA) system at the plant. A. (4.) SPECIAL CONDITION — Spill Notification [G.S. 143-215.1 C.] (a) Contacting Public Health Directors The facility must notify the Iredell and Mecklenburg County Public Health Directors within 12 hours of first knowledge by the owner/operator of any discharge of untreated wastewater to waters of the State or a discharge from the wastewater treatment plant that has not received adequate disinfection due to a malfunctioning treatment unit. The County Public Health Directors can be contacted using the following information: Iredell County Health Director 318 Turmrsburg Highway Statesville, NC 28625 704-878-5300 (b) Public Notification Mecklenburg County Health Director 249 Billingsley Road Charlotte, NC 28211 704-3364700 The facility must notify the public of untreated wastewater spills. Wastewater facility owners or operators must issue a press release after a discharge to surface waters of 1,000 gallons within 24 hours of first knowledge of the spill by the owner/operator. The press release must be issued to "all electronic and print news media outlets that provide general coverage in the county where the discharge occurred." A copy of the press release must be maintained for one year by the owner/operator. This press release is required in addition to the permit requirement of contacting the North Carolina Division of Water Resources (DWR). If a discharge of 15,000 gallons or more reaches surface water, a public notice is required in addition to the press release. The public notice must be placed in a newspaper having general circulation in the County in which the discharge occurred and the county immediately downstream. The owner or operator shall publish the notice within 10 days after the Secretary has determined the countries that are significantly affected by the discharge ,and approved the form and content of the notice and the newspaper in which the notice is to be published. At a minimum the notice should be published in a newspaper of general circulation in Iredell and Mecklenburg Counties. If a discharge of 1,000,000 gallons of wastewater or more reaches surface waters, the DWR regional office must be contacted to determine in what additional counties, if any, a public notice must be published. A copy of these public notices and proof of publication must be sent to the DWR within 30 days of publication. The copy should be sent to the following address: Division of Water Resources PERCS Unit 1617 Mail Service Center Raleigh, NC 27699-1617 The minimum content of the notice is the location of the discharge, estimated volume, water body affected and steps taken to prevent future discharges. Page 6 of 9 Permit NCO074772 A. (5.) ELECTRONIC REPORTING OF DISCHARGE MONITORING REPORTS [G.S. 143-215.1(b)] Federal regulations require electronic submittal of all discharge monitoring reports (DMRs) and program reports. The final NPDES Electronic Reporting Rule was adopted and became effective on December 21, 2015. NOTE: This special condition supplements or supersedes the following sections within Part II of this permit (Standard Conditions for NPDES Permits): • Section B. (11.) • Section D. (2.) • Section D. (6.) • Section E. (5.) Signatory Requirements Reporting Records Retention Monitoring Reports 1. Reporting Requirements (Supersedes Section D. (2.) and Section E. (5.) (a)1 The permittee shall report discharge monitoring data electronically using the NC DWR's Electronic Discharge Monitoring Report (eDMR) internet application. Monitoring results obtained during the previous month(s) shall be summarized for each month and submitted electronically using eDMR. The eDMR system allows permitted facilities to enter monitoring data and submit DMRs electronically using the internet. Until such time that the state's eDMR application is compliant with EPA's Cross -Media Electronic Reporting Regulation (CROMERR), permittees will be required to submit all discharge monitoring data to the state electronically using eDMR and will be required to complete the eDMR submission by printing, signing, and submitting one signed original and a copy of the computer printed eDMR to the following address: NC DEQ / Division of Water Resources / Water Quality Permitting Section ATTENTION: Central Files 1617 Mail Service Center Raleigh, North Carolina 27699-1617 If a permittee is unable to use the eDMR system due to a demonstrated hardship or due to the facility being physically located in an area where less than 10 percent of the households have broadband access, then a temporary waiver from the NPDES electronic reporting requirements may be granted and discharge monitoring data may be submitted on paper DMR forms (MR 1, 1. 1, 2, 3) or alternative forms approved by the Director. Duplicate signed copies shall be submitted to the mailing address above. See "How to Request a Waiver from Electronic Reporting" section below. Regardless of the submission method, the first DMR is due on the last day of the month following the issuance of the permit or in the' case of a new facility, on the last day of the month following the commencement of discharge. Starting on December 21, 2020, the permittee must electronically report the following compliance monitoring data and reports, when applicable: • Sewer Overflow/Bypass Event Reports; • Pretreatment Program Annual Reports; and Clean Water Act (CWA) Section 316(b) Annual Reports. Page 7 of 9 Permit NC0074772 . The permittee may seek an electronic reporting waiver from the Division (see "How to Request a Waiver from Electronic Reporting" section below). 2. Electronic Submissions In accordance with 40 CFR 122.41(1)(9), the permittee must identify the initial recipient at the time of each electronic submission. The permittee should use the EPA's website resources to identify the initial recipient for the electronic submission. Initial recipient of electronic NPDES information from NPDES-regulated facilities means the entity (EPA or the state authorized by EPA to implement the NPDES program) that is the designated entity for receiving electronic NPDES data [see 40 CFR 127.2(b)]. EPA plans to establish a website that will also link to the appropriate electronic reporting tool for each type of electronic submission and for each state. Instructions on how to access and use the appropriate electronic reporting tool will be available as well. Information on EPA's NPDES Electronic Reporting Rule is found at: hMs://www.federalregister.2ov/documents/2015/10/22/2015- 24954/national-pollutant-discharge-elimination-system-nudes-electronic-reporting-rule Electronic submissions must start by the dates listed in the "Reporting Requirements" section above. 3. How to Request a Waiver from Electronic Reporting The permittee may seek a temporary electronic reporting waiver from the Division. To obtain an electronic reporting waiver, a permittee must first submit an electronic reporting waiver request to the Division. Requests for temporary electronic reporting waivers must be submitted in writing to the Division for written approval at least sixty (60) days prior to the date the facility would be required under this permit to begin submitting monitoring data and reports. The duration of a temporary waiver shall not exceed 5 years and shall thereupon expire. At such time, monitoring data and reports shall be submitted electronically to the Division unless the permittee re -applies for and is granted a new temporary electronic reporting waiver by the Division. Approved electronic reporting waivers are not transferrable. Only permittees with an approved reporting waiver request may submit monitoring data and reports on paper to the Division for the period that the approved reporting waiver request is effective. Information on eDMR and the application for a temporary electronic reporting waiver are found on the following web page: htti)://dgg.nc.gov/about/divisions/water-resources/edmr 4. Signatory Requirements [Supplements Section B. (11.) (b) and Supersedes Section B. (11.) (d)1 All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part H, Section B. (11.)(a) or by a duly authorized representative of that person as described in Part II, Section B. (11.)(b). A person, and not a position, must be delegated signatory authority for eDMR reporting purposes. For eDMR submissions, the person signing and submitting the DMR must obtain an eDMR user account and login credentials to access the eDMR system. For more information on North Carolina's Page 8 of 9 Permit NC0074772 eDMR system, registering for eDMR and obtaining an eDMR user account, please visit the following web page: http://dgg.nc.gov/about/divisions/water-resources/edmr Certification. Any person submitting an electronic DMR using the state's eDMR system shall make the following certification [40 CFR 122.22]. NO OTHER STATEMENTS OF CERTIFICATION WILL BE ACCEPTED: V certify, under penalty of law, that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fines and imprisonment for knowing violations. " 5. Records Retention [Supplements Section D. (6.)1 The permittee shall retain records of all Discharge Monitoring Reports, including eDMR submissions. These records or copies shall be maintained for a period of at least 3 years from the date of the report. This period may be extended by request of the Director at any time [40 CFR 122.41). Page 9 of 9 Outfa11001 Lat 350 33' 52" ` Long 80 ° 51' 58" J ` (lake discharge) , WWTPapproximate location Williamson Road / l , �t 11 ! i I 1 � US HWY I-77 AQUA North Carolina Diamond Head Subdivision WWTP Receiving Stream: Lake Norman [Reeds Creek Branch] Stream Segment: I1-(75) Stream Class: WS-IV; B; CA State Grid/Ouad: El5SE / Mooresville, NC River Basin: Catawba River Sub -Basin: 03-08-32 IiuC: 03050101 Facility Location not to scale North NPDES Permit NCO074772 Iredell Count AQUA_ February 28, 2018 Division of Water Resources Water Quality Permitting Section — NPDES Attention: Joe Corporon 1617 Mail Service Center Raleigh, NC 27699-1617 Subject: Comments on Draft Permit Modification Aqua North Carolina, Inc. Diamondhead Subdivision WWTP (WW-2) NPDES No. NCO074772 Iredell County Dear Mr. Corporon, RECEIVED/DENR/DWR MAR ® 5 2018 Water Resources Permitting Section Aqua North Carolina, Inc. (ANC) has reviewed the draft NPDES Permit NC00074772 modification received by our office February 9, 2018, and has summarized our comments below. Section A. (1.) Effluent Limitations and Monitoring Requirements Footnote 8 — We are requesting a period of forty-eight months from the effective date of the revised permit to achieve compliance with the limits imposed by the Changes to the Water Treatment Plant Strategy outlined within this section. Those specific parameters include: • Total Copper • Total Fluoride • Total Chloride • Total Zinc • Alpha emitters (excluding radon and uranium) • Beta emitters (excluding potassium 40 and other naturally occurring radionuclides) • Tritium • Strontium • Uranium We believe that the data collection efforts, studies, evaluations, design, permitting, and modifications could require up to forty-eight months to complete to ensure that we can be in compliance consistently with all of the parameters newly added to the permit. Section A. (1) Footnote 5 We are requesting a period of four years to achieve compliance with limits specified in Section A. (L) that pertains to the compliance limits imposed by the Water Treatment Plant Strategy. Parameters include with this footnote include Total Chloride, Total Fluoride, Total Copper, and Total Zinc. Data collection efforts, studies, evaluations, design, and permitting modifications could require 48 months to complete. Section A. (1) Footnote 7 We are requesting a period of four years to achieve compliance with limits specified in Section A. (L) that pertain the compliance limits imposed by the Water Treatment Plant Strategy. Parameters include with this footnote include Alpha Emitters, Beta emitters, Tritium, Strontium, and Uranium. Data collection efforts, studies, evaluations, design, and permitting modifications could require an additional 48 months to complete. Section A. (1) Footnote 10 The existing footnote, as currently drafted, reads as is if this is a permit limit. Requesting that the footnote be revised to state "Monitor Only" in accordance with the guidance provided by the in the Changes to Water Treatment Plant Strategy document dated October 14, 2009. Section A. (2.) Chronic Toxicity Permit Limit Requesting that "Monitor Only" be included in the header for Section A. (2). in accordance with the guidance provided by the in the Changes to Water Treatment Plant Strategy document dated October 14, 2009. We appreciate your consideration of our comments for this permit revision. If you need any additional information or assistance, please feel free to contact me at 704 489-9404 extension 57234. Sincerely, / Laurie Ison Area Manager 4163 Sinclair Street, Denver, NC, 28037 • 704.489.9404 AquaAmerica.com The Mooresville Tribune Advertising Affidavit PO Box 968 Hickory, NO 28603 NCDENR DIVISION OF WATER RESOURCES ATTN: ACCOUNTS PAYABLE 1611 MAIL SERVICE CENTER RALEIGH, NC 27699-1611 Account Number 3657135 Date February 11, 2018 Date Category Description Ad Number Ad Size 02/11/2018 Legal Notices Pdkkke Nmb tudma Fmhmmwotat MamaameM ComdmK4WO Udt 1617 W15admCMhr laba►t� Bosun Xrtlmdl�tY IsmealpDES waskwdefaml The Ned Cardiia Enthral ManageRsnt Conifil Vow to awes NPDES mast dsdarge part" be on*) EW below. Wdam tamiaih repiling be poposed Pminit will be auepted mM 30 days after be nifish date of ties notice. The CirMor of be NC Dhi aim of Water Reaarces (OWR) may hold a patr0 hearing ME bate be a signimart degree of pEWc interest Please me ammma adym infor. rl reps to DWN at the abwe address Ideresled pars may vis, it N DWR at 512 N. Serialist Street Raleigh, NC to review inform tern on file. Additional informabm m NPDES permit and M aide may to food on Jttp Idea.aax_�dn'dmNratffresoutta /waterrewurtes perm r worstexataH�npdg wastewater(putlir notm,ortry rolling (919) 801-O7. Apia of North femur, la. rest of ad renewal of permit NCWidiR for the Madrid Need WWIP in Iredell Cmmr/, his disdang a treated wastewater to tale Nmnan (tinder Creek Arm) in be Catania ba Bade PoBNh: FeGuary 14101fl Public Notice North Carolina Environmental Management Corny 0000435227 2 x 23 L Publisher of The Mooresville Tribune Iredell County -MT -• -LA Before the undersigned, a Notary Public of Patswba County, North Carolina, duly commissioned, qualified, and authorized by law to administer oaths, in said County and State; that he/she is authorized to make this affidavit and swom statement; that the notice or other legal advertisement, a copy of which is attached hereto, was published in the The Mooresville Tribune on the following dates: 02/11/2018 and that the said newspaper in which such notice, or legal advertisement was published, was a newspaper meeting all the requirements and qualifications of Section 1-597 of the General Statutes of North Carolina. Assistant Bookkeeper Newspaper reference: 0000435227 Swom to and subscribed before me, this Ila. day of &6ALV 2018 Notary Public My Commission expires- 6'Y\ts _—M }[i-�CL THIS IS NOT A BILL. PLEASE PAY FROM INVOICE. THANK YOU 0a ELA Wq rrr�ii� Fly Notory Public Iredell Coun7y = ZQ �i�� CA I210�;�� Corporon, Joe From: Bell, Wes Sent: Thursday, February 01, 2018 4:04 PM To: Corporon, Joe Cc: Basinger, Corey Subject: RE: Draft MOD Review - NC0074772 AQUA Diamond Head WWTP, Iredell County Joe, I have one more clarification request. In regards to footnote #8, is this footnote implying that the facility will not be judged for compliance with the radiological limits if no introduction of offsite wastewater has occurred during the applicable quarter? Wes From: Bell, Wes Sent: Thursday, February 01, 2018 3:50 PM To: Corporon, Joe <joe.corporon@ncdenr.gov> Cc: Basinger, Corey <corey.basinger@ncdenr.gov> Subject: RE: Draft MOD Review- NC0074772 AQUA Diamond Head WWTP, Iredell County Joe, I have no issues with this permit mod except for footnote #9 regarding the weekly average limit/determination for uranium. This footnote is confusing as initially it indicates that the limit is a weekly average limit, then goes on to indicate how a quarterly sample can be determined (one per quarter or averaging of multiple samples not to exceed 7 consecutive days). I know the sample frequency is quarterly, but are you saying that the one sample (if all that is collected for the quarter) will be judged for compliance with the weekly average limit during the week the sample is collected? And secondly (if multiple samples are collected), isn't a weekly average based on the averaging of samples during a calendar week, and not any 7 consecutive days? In addition, I believe edmr is set up to do weekly averages on a calendar week. Thanks for the opportunity to provide comments. Wes From: Basinger, Corey Sent: Thursday, February 01, 2018 3:02 PM To: Bell, Wes <wes.bell@ncdenr.gov> Cc: Pitner, Andrew <andrew.pitner@ncdenr.sov> Subject: FW: Draft MOD Review- NC0074772 AQUA Diamond Head WWTP, Iredell County FYI and comment. Thanks, CB W. Corey Basinger Regional Supervisor Division of Water Resources Mooresville Regional Office Department of Environmental Quality Chairman Water Pollution Control Systems Operator Certification Commission 704-235-2194 office corev.basinoer(ncdenr.00v Mooresville Regional Office 610 East Center Avenue, Suite 301 Mooresville, NC 28115 1C. Nothing Compares ti Email correspondence to and from this address is subject to the North Carolina Public Records Law and may be disclosed to third parties. From: Corporon, Joe Sent: Thursday, February 01, 2018 2:53 PM To: Basinger, Corey <corev. basinger@ncdenr.aov> Cc: Hennessy, John <iohn.hennessv@ncdenr.Qov>; Denard, Derek <derek.denard@ncdenr.gov> Subject: Draft MOD Review- NCO074772 AQUA Diamond Head WWTP, Iredell County Mr. Corey — Please forward as needed for review and comment. It is my intent to submit the attached for Public Notice on 071762018. Respectfully, Joe R. Corporon, L. G. 919-807-6394 NCDEQ/DWR/NPDES Permitting Archdale Building, 925C 1617 Mail Service Center Raleigh, North Carolina 27699 NCDEQ/DWR/NPDES COMPLEX -EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL NPDES Permit NCO074772 Joe R. Corporon, L.G., Compliance & Expedited Permitting Unit / 919-807-6394 02May2017 Table 1 - Facility Information Applicant/Facility Name AQUA North Carolina, Inc. Diamond Head Subdivision W WTP, Class 2 Applicant Address 202 Mackenan Court, Cary, NC 27511 Facility Address 799 Williamson Road, Mooresville Permitted Flow (MGD) Phase 1: 0.0731 MGD, and Phase 2: 0.100 MGD Type of Waste Discharging 100% domestic < IMGD Facility Class WW-2 County Iredell Permit Status Renewal Regional Office MRO Stream Characteristics Receiving Stream Lake Norman [Reeds Creek Arm] Stream Classification WS-IV; B; CA Stream Segment l l-(75) Drainage basin Catawba Summer 7Q10 (cfs) — Subbasin 03-08-32 Winter 7Q 10 (cfs) — Use Support Statewide advisory for Hg [HH for fish consumption] 30Q2 (cfs) — 303(d) Listed Average Flow (cfs) — State Grid E15SE IWC (%) Phase 1 & 2 Lake discharge USGS Quad Mooresville, NC Facility Summary — This facility is a privately owned minor W WTP (flow <1 MGD) receiving 100% domestic wastewater, plus a proposed uranium -filter generated backwash from ion -exchange (IE) treatment of potable -water. The W WTP's extended -aeration treatment system is currently designed for a maximum capacity of 0.0731 MGD, but is permitted to expand to a 21 phase not -to -exceed 0.100 MGD. Expansion requires the Division's Authorization to Construct (ATC). This W WTP utilizes the following treatment units: • influent includes trucked -in filter backwash from potable -water treatment [ion - exchange technology] from Subdivision wells • influent bar screen • V-notch weir • flow -equalization tank • duel (2) aeration basins • dual (2) clarifiers • aerated sludge holding tank • tertiary filters • tablet chlorination / tablet de -chlorination • post aeration • flow recorder • effluent pump station • standby power generator Fact Sheet for Permit Renewal Ma}2017 — NPDES Permit NCO074772 - Page 1 Permit Flow Conditions — Effluent flow is permitted as Phase 1 and Phase 2 (see Part I), and limited at 0.0731 MGD and 0.100 MGD [A. (1.)]. Upon reaching flow at 80% of Phase 1 design capacity, the Permittee shall have submitted plans and specifications to the Division to upgrade the treatment system in support of its application to expand to Phase 2. Expansion requires the Division's Authorization to Construct (ATC) permit and subsequent submittal of an Engineer's Certification Form (see Supplement to Permit Cover Sheet). Table 2 - Effluent Elistory / Summary — DNIR Data Jan2012 through Feb2017 r Paral"xiite� = r , { *c. -- r -~ N- ` �� .. is .._. ..T �.a..'_ _:•. v:CO rT Flow 0.34 0.009 0.036 1885 MGD Dissolved Oxygen 12.7 6.3 9.46 269 mg/L Fecal Coliform 96 1 6.17 239 # / 100m1 TRC 48 2 21.4 538 µg/L BOD s 12.9 2 2.39 270 mg/L pH 8.3 6.3 7.4 269 Standard Units Ammonia 4.68 0.2 0.34 269 Ina TSS 18 2.5 5.04 269 mg/L TP 5.94 1.89 4.39 22 1 mg/L Renewal Summary — This renewal includes new parameters of concern (POCs) originating from potable - water treatment systems utilizing ion -exchange (IE) technology including POCs governing radiological uranium ;filter backwash. Filter -backwash is generated by potable -water treatment of well water systems owned and operated by AQUA. The Permittee proposes to introduce filter backwash episodically by tanker truck into the WWTP's equalization basin for further treatment (rate: Igpm/60gph; proposed not -to -exceed 500 gpd). Radiological POCs — Radiological POCs (see Table 3.) are added to Part I Section A. (L) in accordance with the Division's memo dated December 5, 2005 for Disposal Wastewater Associated with private Water Supply Wells (with potential radiology components). The Division applies permit limits to these POCs without benefit of dilution (lake discharge). North Carolina Narrative Standards 15A NCAC 02B .0211 (17) for Radiological POCs address maximum contaminant levels (MCLs). The MCL of 30 µg//L for Uranium is based on EPA Federal Criteria [40 CFR 141.66]; see federal guidance and rules EPA 816-F-01- 003 and 40 CFR Parts 9,141, and 142. Table 3: Radiological POCs E°FFLUENT OMORING I UIItEMENTS r a. C'HARA 4ERISTICS LIMITS _ t' Measuretneat Sample `Sample [Parameter Codes] Fi _.- uebcv Type . Location Combined radium-226 and radium-228 5 pCi/L (pCi/L)1, 2 11503 (report annual average) Quarterly Grab Effluent Alpha emitters, excluding radon and 15 pCi/L uranium (pCi/L)19 2 82077 (report annual average) Quarterly Grab Effluent Beta emitters, excluding potassium-40 and other naturally occurring 2 03520 50 pCi/L (report annual average) Quarterly Grab Effluent radionuclides (pCi/L)19 Strontium-90 (pCi/L)1' 2 13501 (report weekly average) Quarterly Grab Effluent Tritium Ci/L 1' 2 82126 20,000 pCi/L ort annual averse Quarterly Grab Effluent Uranium (µg/L)1) 3 22708 30 µg//L (report weekly average) Quarterly Grab Effluent Fact Sheet for Permit Renewal May2017 -- NPDES Permit NCO074772 - Page 2 Table 3 Footnotes: 1. All quarterly samples shall be taken 72 to 80 hours after the introduction of offsite wastewater into the equalization tank. If an introduction of offsite wastewater does not occur within a given quarter, a sample shall be taken of the effluent and noted on the DMR as "No introduction of offsite wastewater occurred for this quarter." 2. If the quarterly value exceeds 4 times the annual average limit, then (a) the sampling frequency shall increase to Monthly and (b), a written notification shall be sent to the Water Quality Permitting Section and the Mooresville Regional Office (MRO). 3. A Weekly Average value can be determined from one quarterly sample, or it can be determined from the average of multiple samples taken during a period not to exceed seven (7) consecutive days during the quarter. Adding Water Treatment Plant (WTP) Strategy — This renewal combines the Division's WTP strategies (Oct2009, amended Jun2012) with WWTP strategies to accommodate a proposed complex metals influent (Table 4). This includes monitoring only for dissolved metals with their newly promulgated surface water standards for freshwater [see permit Part I, A. (1.)]. These metals are not limited in the permit because their influent volume (max 500 gpd) was judged insignificant (< 0.01 %) to the average WWTP flow. Likewise, other WTP POCs (Turbidity, Salinity and Conductivity) were deemed insignificant to average inflow. Table 4: POCs for Ion Exchange (IE) Technology - Phase I at 0.032 MGD /IWC=38.27% 17 3�0TIC t—� aVieastire Vent Sain�g , wT w e Cods] .['arameter - ;.�_ :Ayers e: 4NIa,' . 'on , Total Hardness m 192 (.-) 00900 Quarterly Composite Effluent & Upstream Total Copper (mg/L)1'2 01042 7.88 µg/L 10.47 µg/L Quarterly Composite Effiuent Total Chloride (mg/L)1'2 00940 230 µg/L 250 µg/L Quarterly Composite Effluent Total Zinc (mg/L)1'2 01092 125.7 µg/L 125.7 µg/L Quarterly Composite Effluent Chronic WET Testing 3 TGP3B Quarterly Grab Effluent Footnotes: 1. All test -method practical quantitation limits (PQL) must be sufficiently sensitive considering the respective permit limit for each parameter of concern [see permit Part U. Section D. (4.)]. 2. All quarterly samples shall be taken 72 to 80 hours after the introduction of offsite wastewater into the equalization tank. If an introduction of offsite wastewater does not occur within a given quarter, a sample shall be taken of the effluent and noted on the DMR as "No introduction of offsite wastewater occurred for this quarter". 3. Phase I flow - Chronic Toxicity (Ceriodaphnia dubia) test at 90% in January, April, July and October [See A. (6.)]. Ouarterlv Whole Effluent Toxicity (WET) Testing — In accordance with current strategies designating this proposed new influent as a "complex waste stream," WET testing has been added to this permit as fresh water Chronic [TGP3B] Quarterly monitoring [15A NCAC 02B .0200 et seq.]. Fact Sheet for Permit Renewal May2017 -- NPDES Permit NCO074772 - Page 3 NPDES Implementation of Instream Dissolved Metals Standards - Freshwater Standards The NC 2007-2015 Water Quality Standard (WQS) Triennial Review was approved by the NC Environmental Management Commission (EMC) on November 13, 2014. The US EPA subsequently approved the WQS revisions on April 6, 2016, with some exceptions. Therefore, metal limits in draft permits out to public notice after April 6, 2016 must be calculated to protect the new standards - as approved. Table 5. NC Dissolved Metals Water Oualitv Standards/Aauatic Life Prateetian Parameter Acute 'W, µfill , :(D�ssoloed) Chronic FW, µg/l 0) ssolyed)... Acute SW, µg/1 . (Dissolved) Chronic SW, µg/1 Dissolved) Arsenic 340 150 69 36 Beryllium 65 6.5 --- --- Cadmiumalcilation` -Calew &on 40 8.8 Chromium III. 116 ?Catlt{i�#n--- Chromium VI 11 1100 50 Copper 4al.8 3.1 Leada�ciilaz - 210 8.1 Nickel Caeuao 'a1cuIa�ori 74 8.2 Silver :Calculaon . 0.06 1.9 0.1 Zinc Clculation:= - Alt on, _.,.. - ..: 90 81 Table 3 Notes: 1- FW= Freshwater, SW= Saltwater 2. ` ' L- ` = Hardness de pendent standard I Only the aquatic life standards listed above are expressed in dissolved form. Aquatic life standards for mercury and selenium are still expressed as Total Recoverable Metals due to bioaccumulative concerns (as are all human health standards for all metals). It is still necessary to evaluate total recoverable aquatic life and human health standards listed in 15A NCAC 2B.0200 (e.g., arsenic at 10 µg/1 for human health protection; cyanide at 5 µg/L and fluoride at 1.8 mg/L for aquatic life protection). Table 6. Dissolved Freshwater Standards for Hardness -Dependent Metals The Water Effects Ratio (WER) is equal to one unless determined otherwise under 15A NCAC 02B .0211 Subparagraph (11)(d) Metal NC Dissolved Standard, µo Cadmium, Acute WER*{1.136672-[In hardness](0.041838)} • e^{0.9151 [In hardness]-3.1485} Cadmium, Acute Trout waters WER*{1.136671[ln hardness](0.041838)} • e^{0.9151[ln hardness]-3.6236} Cadmium, Chronic WER*{1.101672-[In hardness](0.041838)} • e^{0.7998[In hardness]-4.4451} Chromium III, Acute WER*0.316 • e^{0.8190[In hardness]+3.7256} Chromium III, Chronic WER*0.860 • e^{0.8190[In hardness]+0.6848} Copper, Acute WER*0.960 • e^(0.9422[ln hardness]-1.700) Copper, Chronic WER*0.960 • e^{0.8545[ln hardness]-1.702) Lead, Acute WER* {1.46203-[In hardness](0.145712) } • e^ { 1.273 [in hardness]-1.460} Lead, Chronic WER* { 1.46203-[In hardness](0.145712)) • e^ { 1.273 [ln hardness]-4.705 } Nickel, Acute WER*0.998 • e^{0.8460[In hardness]+2.255} Fact Sheet for Permit Renewal May2017 -- NPDES Permit NCO074772 - Page 4 Nickel, Chronic WER*0.997 e"{.0 84G0[In hardaess�+0:0594 Silver; Acute WER;f 85 •` e^ 1- 72[Iri=hardness]=6 59} Silver; Cluoiic Not applicable ; Zinc;:Acute WER*0:978 ' e . {0:8473[In'hardness]+0 8$4} Zinc, Chronic WEV0.986 - e^ {0.8473 [ln hardness]+0.884} General Information on the Reasonable Potential Analysis (RPA) The RPA process itself did not change as the result of the new metals standards. However, application of the dissolved and hardness -dependent standards requires additional consideration in order to establish the numeric standard for each metal of concern of each individual discharge. The hardness -based standards require some knowledge of the effluent and instream (upstream) hardness and so must be calculated case -by -case for each discharge. Metals limits must be expressed as `total recoverable' metals in accordance with 40 CFR 122.45(c). The discharge -specific standards must be converted to the equivalent total values for use in the RPA calculations. We will generally rely on default translator values developed for each metal (more on that below), but it is also possible to consider case -specific translators developed in accordance with established methodology. RPA Permitting Guuidance/W BELs for Hardness -Dependent Metals - Freshwater The RPA is designed to predict the maximum likely effluent concentrations for each metal of concern, based on recent effluent data, and calculate the allowable effluent concentrations, based on applicable standards and the critical low -flow values for the receiving stream. If the maximum predicted value is greater than the maximum allowed value (chronic or acute), the discharge has reasonable potential to exceed the standard, which warrants a permit limit in most cases. If monitoring for a particular pollutant indicates that the pollutant is not present (i.e. consistently below detection level), then the Division may remove the monitoring requirement in the reissued permit. 1. To perform a RPA on the Freshwater hardness -dependent metals the Permit Writer compiles the following information: • Critical low flow of the receiving stream, 7Q 10 (the spreadsheet automatically calculates the 1 Q 10 using the formula 1 Q 10 = 0.843 (s7Q 10, cfs) "" • Effluent hardness and upstream hardness, site -specific data is preferred • Permitted flow • Receiving stream classification 2. In order to establish the numeric standard for each hardness -dependent metal of concern and for each individual discharge, the Permit Writer must first determine what effluent and instream (upstream) hardness values to use in the equations. The permit writer reviews DMR's, Effluent Pollutant Scans, and Toxicity Test results for any hardness data and contacts the Permittee to see if any additional data is available for instream hardness values, upstream of the discharge. If no hardness data is available, the permit writer may choose to do an initial evaluation using a default hardness of 25 mg/L (CaCO3 or (Ca + Mg)). Minimum and maximum limits on the hardness value used for water quality calculations are 25 mg/L and 400 mg/L, respectively. Fact Sheet for Permit Renewal May2017 -- NPDES Permit NC0074772 - Page 5 If the use of a default hardness value results in a hardness -dependent metal showing reasonable potential, the permit writer contacts the Permittee and requests 5 site -specific effluent and upstream hardness samples over a period of one week. The RPA is rerun using the new data. The overall hardness value used in the water quality calculations is calculated as follows: Combined Hardness (chronic) = (Permitted Flow, cfs *Avg. Effluent Hardness mg ) + (s7Q 10. cfs *Avg_Upstream Hardness, mg/L) (Permitted Flow, cfs +s7Q 10, cfs) The Combined Hardness for acute is the same but the calculation uses the IQ 10 flow. 3. The permit writer converts the numeric standard for each metal of concern to a total recoverable metal, using the EPA Default Partition Coefficients (DPCs) or site -specific translators, if any have been developed using federally approved methodology. EPA default partition coefficients or the "Fraction Dissolved" converts the value for dissolved metal at laboratory conditions to total recoverable metal at in+stream ambient conditions. This factor i"s calculated using.the linear partition coefficients found in The Metals Translator.-: Guidance for Calculating a Total Recoverable Permit Limit; from, a Dissolved Gtiteriori (EPA 823-B-96=007, June 1996) and the equation: Cdiss I Ctotal I + { [Kpo] (ss11+8)] [10`6] } Where: ss = in -stream suspended solids concentration [mg/ll,, minimum of 10 mg/L used; and Kpo and a constants that express the equilibriuin:relationship between dissolved -and adsorbed forms of metals. A list of constants used for each hardness -dependent metal .can also be found in the RPA program under a sheet labeled !)PCs. 4. The numeric standard for each metal of concern is divided by the default partition coefficient (or site -specific translator) to obtain a Total Recoverable Metal at ambient conditions. In some cases, where an EPA default partition coefficient translator does not exist (i.e. silver), the dissolved numeric standard for each metal of concern is divided by the EPA conversion factor to obtain a Total Recoverable Metal at ambient conditions. This method presumes that the metal is dissolved to the same extent as it was during EPA's criteria development for metals. For more information on conversion factors see the June, 1996 EPA Translator Guidance Document. 5. The RPA spreadsheet uses a mass balance equation to determine the total allowable concentration (permit limits) for each pollutant using the following equation: Ca = (s7Q 10 + Qw) Cwgs) — (s7Q 10) (Cb) Qw Where: Ca = allowable effluent concentration (µg/L or mg/L) Cwqs = NC Water Quality Standard or federal criteria (µg/L or mg/L) Cb = background concentration: assume zero for all toxicants except NH3* (µg/L or mg/L) Qw = permitted effluent flow (cfs, match s7Q 10) s7Q 10 = summer low flow used to protect aquatic life from chronic toxicity and human health through the consumption of water, fish, and shellfish from noncarcinogens (cfs) * Discussions are on -going with EPA on how best to address background concentrations Fact Sheet for Permit Renewal May2017 -- NPDES Permit NCO074772 - Page 6 Flows other than s7Q 10 may be incorporated as applicable: IQ 10 = used in the equation to protect aquatic life from acute toxicity QA = used in the equation to protect human health through the consumption of water, fish, and shellfish from carcinogens 30Q2 = used in the equation to protect aesthetic quality 6. The permit writer enters the most recent 2-3 years of effluent data for each pollutant of concern. Data entered must have been taken within four and one-half years prior to the date of the permit application (40 CFR 122.21). The RPA spreadsheet estimates the 95th percentile upper concentration of each pollutant. The Predicted Max concentrations are compared to the Total allowable concentrations to determine if a permit limit is necessary. If the predicted max exceeds the acute or chronic Total allowable concentrations, the discharge is considered to show reasonable potential to violate the water quality standard, and a permit limit (Total allowable concentration) is included in the permit in accordance with the U.S. EPA Technical Support Document for Water Quality -Based Toxics Control published in 1991. 7. When appropriate, permit writers develop facility specific compliance schedules in accordance with the EPA Headquarters Memo dated May 10, 2007 from James Hanlon to Alexis Strauss on 40 CFR 122.47 Compliance Schedule Requirements. 8. The Total Chromium NC WQS was removed and replaced with trivalent chromium and hexavalent chromium Water Quality Standards. As a cost savings measure, total chromium data results may be used as a conservative surrogate in cases where there are no analytical results based on chromium III or VI. In these cases, the projected maximum concentration (95th %) for total chromium will be compared against water quality standards for chromium III and chromium VI. 9. Effluent hardness sampling and instream hardness sampling, upstream of the discharge, are inserted into all permits with facilities monitoring for hardness -dependent metals to ensure the accuracy of the permit limits and to build a more robust hardness dataset. 10. Table 7 - Hardness / Flow Values [in the absence of data] to be used in the Reasonable Potential Analysis (RPA): Parameter Value Comments (Data Source) Average Effluent Hardness (mg/L) mg/L 25 m Assumed (no data to date); added [Total as, CaCO3 or (Ca+Mg)] monitoring to create database Average Upstream Hardness (mg/L) 25m Assumed (no data to date); added [Total as, CaCO3 or (Ca+Mg)] monitoring to create database 7Q 10 summer (cfs) 0.08 cfs Phase 1 flow [Outfall 001 ] 0.034 cfs Phase 2 flow [Outfall 002] IQ 10 (cfs) Perini Flo (MG 0.032 MGD Phase 1 flow [Outfall 001 ] 0.185 MGD Phase 2 flow [Outfall 002] r� wiffina0 Fact Sheet for Permit Renewal May2017 -- NPDES Permit NC0074772 - Page 7 A U X Shannon V. Becker, President 0:919.653.5770 • F:919.460.1788 • SVBecker@AquaAmerica.com November 20, 2017 NC Department of Environmental Quality Division of Water Resources Water Quality Permitting Section — NPDES Attention: Mr. John Hennessey 1617 Mail Service Center Raleigh, NC 27699-1617 Subject: Application for Permit Modification Aqua North Carolina, Inc. Diamond Head WWTP, NPDES No. NC0074772 Iredell County Dear Mr. Hennessey: This letter and attached processing fee are being submitted with our request to modify the subject permit to allow for a compliance period to meet the new limits which were added in the recent modification allowing for the introduction of backwash from Aqua's potable water systems. This request would allow Aqua to investigate possible treatment, modeling, testing and possibly adjusting permit limits for Total Conner to account for the domestic discharge currently being discharged into the WWTP. During the investigation and subsequent modification to the permit it has become evident that the domestic wastewater currently being treated at the WWTP exceed the minimum level of Total Copper as no backwash has yet to be introduced into the facility under the new permit. We appreciate your consideration of this request for modification. If you need any additional information or assistance, please feel free to contact Laurie Ison at 704-489-9404. Sincerely, /% ae�1 Shannon V. Becker President 202 MacKenan Court, Cary, NC 27511 • AquaAmerica.com METHOD 9310 GROSS ALPHA AND GROSS BETA 1.0 SCOPE AND APPLICATION 1.1 This method covers the measurement of gross alpha and gross beta particle activities in surface and ground waters. 1.2 The method is applicable to the measurement of alpha emitters having energies above 3.9 mega electron volts (MeV) and beta emitters having maximum energies above 0.1 MeV. 1.3 The minimum limit of concentration to which this method is applicable depends on sample size, counting -system characteristics, background, and counting time. 1.4 Because, in this method for gross alpha and gross beta measurement, the radioactivity of the sample is not separated from the solids of the sample, the solids concentration is very much a limiting factor in the sensitivity of the method for any given water sample. Also, for samples with very low concentrations of radioactivity, it is essential to analyze as large a sample aliquot as is needed to give reasonable times. 1.5 The largest sample aliquot that should be counted for gross alpha activity is that size aliquot which gives a solids density thickness of 5 mg/cm' in the counting planchet. For a 2-in. diameter counting planchet (20 cm'), an aliquot containing 100 mg of nitrated dissolved solids would be the maximum aliquot size for that sample which should be evaporated and counted for gross alpha activity. 1.6 When the concentration of total solids (TS) is known for a given water sample and the alpha background and the counting efficiency of a given counting system are known, the counting time that is needed to meet the required sensitivity (3 pCi/L) can be determined by equations given in Appendix C. 1.7 For the counting of gross beta activity in a water sample, the TS is not as limiting as for gross alpha activity because beta particles are not stopped in solids as easily as are alpha particles. Very often a single sample aliquot is evaporated and counted for both gross alpha and gross beta activity. In that case, the sample aliquot size would be dictated by the solids limitations for alpha particles. For water samples that are to be counted for gross beta activity, equations in Appendix C can also be used to determine the necessary counting time to meet a sensitivity for gross beta activity (4 pCi/L). 1.8 Radionuclides that are volatile under the sample preparation conditions of this method will not be measured. In some areas of the country the nitrated water solids (sample evaporated with nitric acid present) will 9310 — 1 CD-ROM Revision 0 Date September 1986 not remain at a constant weight after being dried at 1050C for 2 hr and then exposed to the atmosphere before and during counting. Other radioactivities (such as some chemical forms of radioiodine) may also be lost during the sample evaporation and drying at 105°C. Those types of water samples need to be heated to a dull red heat for a few minutes to convert the salts to oxides. Sample weights are then usually sufficiently stable to give consistent counting rates, and a correct counting efficiency can then be assigned. Some radioactivities, such as the cesium radioisotopes, may be lost when samples are heated to a dull red color. Such losses are limitations of the test method. 1.9 This method provides a rapid screening measurement to indicate whether specific analyses are required. When the gross alpha particle activity exceeds 5 pCi/L, the same or an equivalent sample shall be analyzed for alpha -emitting radium isotopes (Method 9315) or an alternative measurement of radium-226 alpha emission (Standard Methods for the Examination of Water and Wastewater, 15th edition, Method 705 or 706, respectively). Gross beta particle emissions exceeding 15 pCi/L in a sample shall be analyzed for strontium-89 and cesium-134 (Standard Methods for the Examination of Water and Wastewater, 15th edition, Methods 704 and 709, respectively). If gross beta activity exceeds 50 pCi/L, the identity of the major radioactive constituents must be evaluated and the appropriate organ and total body doses determined. 2.0 SUMMARY OF METHOD 2.1 An aliquot of a preserved water sample is evaporated to a small volume and transferred quantitatively to a tared 2-in. stainless steel counting planchet. The sample residue is dried to constant weight, reweighed to determine dry residue weight, and then counted for alpha and/or beta radioactivity. 2.2 Counting efficiencies for both alpha and beta particle activities are selected according to the amount of sample solids from counting efficiency vs. sample solids standard curves. 3.0 INTERFERENCES 3.1 Moisture absorbed by the sample residue is an interference because it obstructs counting and self-absorption characteristics. If a sample is counted in an internal proportional counter, static charge on the sample residue can cause erratic counting, thereby preventing an accurate count. 3.2 Nonuniformity of the sample residue in counting planchet interferes with the accuracy and precision of the method. 3.3 Sample density on the planchet area should be not more than 10 mg/cm2 for gross alpha and not more than 20 mg/cm' for gross beta. 9310 — 2 CD-ROM Revision 0 Date September 1986 3.4 When counting alpha and beta particle activity by a gas -flow proportional counting system, counting at the alpha plateau discriminates against beta particle activity, whereas counting at the beta plateau is sensitive to alpha particle activity present in the sample. This latter effect should be determined and compensated for during the calibration of the specific instrument being used. 4.0 APPARATUS AND MATERIALS 4.1 Gas -flow proportional counting system, or 4.2 Scintillation detection system, or 4.3 Stainless steel counting planchets. 4.4 Electric hot 1p ate. 4.5 Drying oven. 4.6 Drying lamp. 4.7 Glass desiccator. 4.8 Glassware. 4.9 Analytical balance. 5.0 REAGENTS 5.1 All chemicals should be of "reagent -grade" or equivalent whenever they are commercially available. 5.2 Distilled or deionized water (Type II) having a resistance value between 0.5 and 2.0 megaohms (2.0 to 0.5 mhos)/cm at 25°C. 5.3 Nitric acid, 1 N: Mix 6.2 mL 16 N HNO3 (conc.) with deionized or distilled water and dilute to 100 mL. 6.0 SAMPLE -COLLECTION, PRESERVATION, AND HANDLING 6.1 All samples must have been collected in a manner which addresses the considerations discussed in Chapter Nine of this manual. 6.2 It is recommended that samples be preserved at the time of collection by adding enough 1 N HNO3 to the sample to bring it to pH 2 (15 mL 1 N HNO3 per liter of sample is usually sufficient). If samples are to be collected without preservation, they should be brought to the laboratory within 5 days and then preserved and held in the original container for a minimum of 16 hr before analysis or transfer of the sample. 9310 — 3 CD-ROM Revision 0 Date September 1986 6.3 The container choice should be plastic rather than glass to prevent loss due to breakage during transportation and handling. 7.0 PROCEDURE 7.1 Calibration 7.1.1 For absolute gross alpha and gross beta measurement, the detectors must be calibrated to obtain the ratio of count rate to disintegration rate. Americium-241 (used for alpha activity in the collaborative test of this method) has higher alpha particle energy and radium-226 radionuclides but is close to the energy of the alpha particles emitted by naturally occurring thorium-228 and radium-224. Standards should be prepared in the geometry and weight ranges to be encountered in these gross analyses. It is, therefore, the prescribed radionuclide for gross alpha calibration. NBS or NBS-traceable americium-241 is available from Standard Reference Materials Catalog, NBS Special Publications 260, U.S. Department of Commerce (1976) and from Quality Assurance Branch, EMSL-LV, P.O. Box 15027, Las Vegas, Nevada 89114. 7.1.2 Strontium-90 and cesium-137 have both been used quite extensively as standards for gross beta activity. Standard solutions of each of these radionuclides are readily available. Cesium is volatile at elevated temperatures (above 4500C). Some water supplies have dissolved solids (salts) that, when converted to nitrate salts, are quite hygroscopic and need to be converted to oxides by heating to red heat to obtain sample aliquots that are weight -stable. Sample weight stability is essential to gross alpha and gross beta measurements to ensure the accuracy of the self- absorption counting efficiency factor to be used for the samples. Strontium-90 in equilibrium with its daughter yttrium-90 is the prescribed radionuclide for gross beta calibrations. 7.1.3 For each counting instrument to be used, the analyst should prepare separate alpha and beta particle self-absorption graphs showing water sample residue weight (mg) vs. the efficiency factor (cpm/dpm), using standard alpha and beta emitter solutions and tap water. For the alpha graph standard, alpha activity is added to varying sizes of aliquots of tap water such that the aliquot residue weight is varied between 0 and 100 mg (for a 2-in. counting planchet). A similar graph is prepared with standard beta activity and tap -water aliquots, varying the residue weight between 0 and 300 mg (for a 2-in. planchet). If it is planned to use water -sample aliquot volumes that always contain 100 mg of dried water solids, then only the efficiency factor for that residue weight needs to be established. 7.1.4 Tap water aliquots, with added americium-241 or strontium-90 standard, should be acidified with a few mL 16 N HNO3, evaporated to a small volume in a beaker on a hot plate, transferred quantitatively in 5-mL portions or less to a tared counting planchet, evaporated to dryness, and finally dried at 1050C for 1 hr (or flamed to a red heat if dried 9310 — 4 CD-ROM Revision 0 Date September 1986 solids appear to be noticeably hygroscopic). Weight -stable aliquot residues should then be alpha and/or beta counted until at least 10,000 total counts have been accumulated. A single set of reference standards prepared in this way can be used for each counting instrument for separate graph preparations and can be stored for reverification whenever needed. 7.2 Transfer to a beaker an aliquot of water sample of a volume that contains no more than 100 mg (for alpha only or alpha and beta determination) or 200 mg (for beta only determination) of total water solids. Evaporate the aliquot to near dryness on a hot plate. If water samples are known or suspected to contain chloride salts, those chloride salts should be converted to nitrate salts before the sample residue is transferred to a stainless steel planchet (chlorides will attack stainless steel and increase the sample solids, and no correction can be made for those added solids). Chloride salts can be converted to nitrate salts by adding 5-mL portions of 16 N HNO3 to the sample residue and evaporating to near dryness. (Two treatments are usually sufficient.) Add 10 mL 1 N HNO3 to the beaker and swirl to dissolve the residue. Quantitatively transfer the aliquot concentrate in small portions (not more than 5 mL at a time) to a tared planchet, evaporating each portion to dryness. 7.3 Dry the sample residue in a drying oven at 105°C for at least 1 hr, cool in a desiccator, weigh, and count. Store the sample residue in a desiccator until ready for counting. 7.4 Some types of water -dissolved solids, when converted to nitrate salts, are quite hygroscopic even after being dried at 1050C for 1 hr. When such hygroscopic salts are present with samples that are put into an automatic counting system, those samples gain weight while they are waiting to be counted, and inaccurate counting data result. When there is evidence of hygroscopic salts in sample counting planchets, it is recommended that they be flamed to a dull red heat with a Meeker burner for a few minutes to convert the nitrate salts to oxides before weighing and counting. (It is possible to have a loss of cesium during the flaming of the samples.) 7.5 Count for alpha and beta activity at their respective voltage plateaus. If the sample is to be recounted for reverification, store it in a desiccator. NOTE: As long as counting chambers are capable of handling the same size planchet, alpha and beta activities can be determined at their respective voltage plateaus in the designated counting instruments. Keep the planchet in the desiccator until ready to count because vapors from moist residue can damage detector and window and can cause erratic measurements. If the gas -flow internal proportional counter does not discriminate for the higher energy alpha pulses at the beta plateau, the alpha activity must be subtracted from the beta plus alpha activity. This is particularly important for samples with high alpha activity. 9310 — 5 CD-ROM Revision 0 Date September 1986 7.6 Calculations: l 7.6.1 Calculate the alpha radioactivity by the following equation: Alpha (pCi/liter) = A x 1,000 2.22xCxV where: A = net alpha count rate (gross alpha count rate minus the background count rate) at the alpha voltage plateau; C = alpha efficiency factor, read from the graph (Paragraph 7.1.3) of efficiency vs. mg of water solids per cm' of planchet area, cpm/dpm); V = volume of sample aliquot (mL); and 2.22 = conversion factor from dpm/pCi. 7.6.2 Calculate the beta radioactivity by the following equations: 7.6.2.1 If there are no significant alpha counts when the sample is counted at the alpha voltage plateau, the beta activity can be determined from the following equation: Beta (pCi/liter) = B x 1,000 2.22xDxV where: B = net beta count rate (gross alpha count rate minus the background count rate at the beta voltage plateau), D = beta efficiency factor, read from the graph (Paragraph 7.1.3) of efficiency vs. mg of water solids per cm2 of planchet area, (cpm/dpm). V = volume of sample aliquot (mL). 2.22 = conversion factor from dpm/pCi. 7.6.3 When counting beta radioactivity in the presence of alpha radioactivity by gas -flow proportional counting systems (at the beta plateau), alpha particles are also counted. Because alpha particles are more readily absorbed by increasing sample thickness than beta particles, the alpha/beta count ratios vary with increasing sample thickness. Therefore, it is necessary to prepare a calibration curve by counting standards containing americium-241 with increasing thickness of solids on 9310 — 6 CD-ROM Revision 0 Date September 1986 the alpha plateau and then on the beta plateau, plotting the ratios of the two counts vs. density thickness. The alpha amplification factor (E) from that curve is used to correct the amplified alpha count on the beta plateau. When significant alpha activity is indicated by the sample count at the alpha voltage plateau, the beta activity of the sample can be determined by counting the sample at the beta voltage plateau and calculating the activity from the following equation: Beta (pCi/liter) = (B - AE) x 1,000 2.22xDxV where: B = as defined above. D = as defined above. A = as defined above. E = alpha amplification factor, read from the graph of the ratio of alpha counted at the beta voltage/alpha counted at the alpha voltage vs. sample density thickness. V = volume of sample aliquot W ). 2.22 = conversion factor from dpm/pCi. 7.7 Errors associated with the results of the analysis should also be reported. 8.0 QUALITY CONTROL 8.1 All quality control data should be maintained and available for easy reference or inspection. 8.2 Employ a minimum of one blank per sample batch to determine if contamination is occurring. 8.3 Run one duplicate sample for every 10 samples. A duplicate sample is a sample brought through the whole sample -preparation and analytical process. 8.4 Spiked samples or standard reference materials shall be periodically employed to ensure that correct procedures are being followed and that all equipment is operating properly. 9310 — 7 CD-ROM Revision 0 Date September 1986 9.0 METHOD PERFORMANCE 9.1 In a collaborative study of two sets of paired water samples containing known additions of radionuclides, 15 laboratories determined the gross alpha activity and 16 analyzed gross beta activity. The samples contained simulated water minerals of approximately 350 mg fixed solids/L. The alpha results of one laboratory were rejected as outliers. The average recoveries of added gross alpha activity were 86, 87, 84, and 82%. The precision (random error) at the 95% confidence level was 20 and 24% for the two sets of paired samples. The method was biased low, but not seriously. The average recoveries of added gross beta activity were 99, 100, 100, and 100%. The precision (random error) at the 95% confidence level was 12 and 18% for the two sets of paired samples. The method showed no bias. 10.0 REFERENCES 10.1 None required. 9310 — 8 CD-ROM Revision 0 Date September 1986 METHOD 9310 GROSS ALPHA AND GROSS BETA Start A B 7.1 Calibrate using Am-241 for gross 7.2 7.6.1 Calculate alpha alpha activity; Sr-90 p Does water Yes 7.2 Convert to radioactivity. or Cs-137 for gross sample contain nitrate salts. beta activity. chloride salts? No 7.6.2 Calculate beta 7.1.3 Prepare separate alpha radioactivity. and beta particle self-absorption 7.2 Add HNO ,swirl; transfer eachaliquotgraphs. to tard planchet; evaporate. Stop 7.1.4 Acidify tap water aliquots with HNO3; evaporate; 7.3 Dry sample transfer to residue; weigh planchet. and count. 7.1.4 Evaporate and dry: count alpha, beta 7.4 residue for reference hygroscopic AreYes 7.4 Flame to a standard. salts dull red heat. present? 7.2 Transfer aliquot No of water sample to beaker; evaporate. 7.5 Weigh and count. A B 9310 — 9 CD-ROM Revision 0 Date September 1986