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Home My WebLink AboutWQ0002284_Staff Comments_20011219DIVISION OF WATER QUALITY GROUNDWATER SECTION December 17, 2001-- - - - - MEMORANDUM To: Kim Colson ! J DEC 19 2001 Through: Debra Watts — - - —"� RFm, N'L UFFIC[ i w�llie_Iardison,GW-S-RO _ --- _L-- -- `— From: David Goodrich i�� Subject: Outer Banks — Kinnakeet Shores / High -Rate Rotary Distributor System Dare County WQ0002284/GW01066 The Groundwater Section is in receipt of the subject application to renew existing Permit Number WQ0002284, issued on September 20, 1999. The existing permit allows the use of a 50,000 GPD rotary distributor system which includes chlorination and two 80-foot diameter rotary distributor units (see Figures 1 and 2). The system treats the (mostly domestic) wastewater stream generated by the Kinnakeet Shores residential subdivision. It is the understanding of the Groundwater Section that the 50,000 GPD discharge level will, in all likelihood, not be achieved for another five years as the subdivision expands. In June of 2000, the Division of Water Quality received a request from the permittee to increase the maximum allowable discharge from 50,000 GPD to 220,000 GPD with the addition of more rotary units. The application site was used for the deposition of large volumes of dredge material (taken from the adjacent sound) in January of 1999, and there was concern that the presence of this dredge material could impair the operation of the proposed additional rotary units. A consultant performed a hydrologic analysis of the site and found that the presence of the dredge material had impacted the quality of the shallow and deep ground water. The consultant concluded that the presence of the dredge material and the saline ground water would not materially impact the ability of the expanded rotary system to handle the intended loading of 220,000 GPD. The Division concurred with these findings, as the addition of the dredge material to the surface of the site had not altered the geology beneath the site, nor was there reason to believe that the ability of the dredge material to transmit water was significantly less than the native soil. The existing permit requires the permittee to monitor four existing wells (MW-1, MW-2, MW- 3, and MW-4) every February, June, and September for Water Level, pH, Chloride, Total Dissolved C:/My Documents/ GW01066A.doc Page 1 of 4 Shl Doc 07/01 .1 Solids, Fecal Coliforms, Total Organic Compounds, Nitrate Nitrogen, and Ammonia Nitrogen. An examination of our records indicates that required monitoring data has not been received from this facility since September of 1998. It is the understanding of the Groundwater Section that the four wells were destroyed when the dredge material was deposited and that four new monitor wells (MW-S, MW-6, MW-7, and MW-8) were constructed to replace wells MW-1, MW-2, MW-3, and MW4. The data received for the original wells prior to September of 1998 indicated moderate to high concentrations of Chloride, Total Dissolved Solids, Fecal Coliforms, Total Organic Compounds, Nitrate Nitrogen, and Ammonia Nitrogen with no apparent trends. Data received for the new wells during the year 2000 indicate a possible trend in elevated TDS concentrations for monitor wells MW-6, MW-7, and MW-8. The year 2001 data indicate elevated concentrations of Fecal Coliforms in MW-7 and MW-8. More data is needed to verify the possible existence of these trends. In view of these results a Ad umstances, the Groundwater Section recommends that the new wells (MW-5, MW-6, MW-7,Aand be sampled every February, June, and September for Water Level, pH, Chloride, Total Dissolved Solids, Fecal Coliforms, Total Organic Compounds, Nitrate Nitrogen, Total Ammonia Nitrogen, and Volatile Organic Compounds (in September only). The Groundwater Section has reviewed the subject permit renewal application and recommends reissuance of the permit with the following conditions: 1. Sampling Criteria: M\#J -8 *a. Existing monitor wells MW-5, MW-6, MW-7,Aand MW-1 shall be sampled every February, June, and September for the parameters listed below. Prior to sampling the parameters, the measurement of water levels must be taken. The depth to water in each well shall be measured from the surveyed point on the top of the casing. The measuring points (top of well casing) of all monitoring wells shall be surveyed relative to a common datum. Water Level pH Chloride Total Dissolved Solids Fecal Coliforms Total Organic Compounds Nitrate Nitrogen (NO3-N) Total Ammonia Nitrogen (NH3-N) Volatile Organic Compounds (in. September only) b. For Total Organic Carbon (TOC), if concentrations greater than 10 mg/l are detected in any downgradient monitoring well, additional sampling and analysis must be conducted to identify the individual constituents comprising this TOC concentration. If the TOC concentration as measured in the background monitor well exceeds 10 mg/l, this concentration will be taken to represent the naturally occurring TOC concentration. Any exceedances of this naturally occurring TOC concentration in the down -gradient wells shall be subject to the additional sampling and analysis as described above. * This verbage differs from that of the shell document. C:/My Documents/ GW01066A.doc Page 2 of 4 Shl Doc 07/01 C. For Volatile Organic Compounds (VOCs) sampled in September, use only one of the following methods: (1) Standard Method 6230D, PQL at 0.5 ug/L or less (2) Standard Method 6210D, PQL at 0.5 ug/L or less (3) EPA Method 8021, Low Concentration, PQL at 0.5 ug/L or less (4) EPA Method 8260, Low Concentration, PQL at 0.5 ug/L or less (5) Another method with prior approval by the Groundwater Section Chief Any of the referenced methods used for VOCs must, at a minimum, include all the constituents listed in Table VIII of Standard Method 6230D. Any method used must provide a PQL of 0.5 ug/L or less, which must be supported by laboratory proficiency studies as required by the DWQ Laboratory Certification Unit. Any constituents detected above the Method Detection Limit (MDL) but below the PQL of 0.5 ug/L must be qualified (estimated) and reported. d. Any laboratory selected to analyze parameters must be Division of Water Quality (DWQ) certified for those parameters required. 2. Reporting / Documentation a. All reports and documentation (GW-59) shall be mailed to the following address: Groundwater Section Permits and Compliance Unit 16365 Mail Service Center Raleigh, NC 27699-1636 Updated blank forms (GW-59) may be downloaded from the Groundwater Section's website at http://gw.ehnr.state.nc.us/ or requested from the address mentioned above. b. The results of the sampling and analysis must be received on Form GW-59 (Groundwater Quality Monitoring: Compliance Report Form) by the Groundwater Section (address listed in the "Reporting / Documentation" section of the Groundwater Requirements), on or before the last working day of the month following the sampling month. The data of all groundwater sampling analyses required by the permit conditions must be reported using the most recent GW-59 form along with attached copies of the laboratory analyses. 3. Applicable Boundaries a. The COMPLIANCE BOUNDARY for the disposal system is specified by regulations in 15A NCAC 2L, Groundwater Classifications and Standards. The Compliance Boundary for a disposal system individually permitted after December 31, 1983 is established at C:/My Documents/ GW01066A.doc Page 3 of 4 Shl Doc 07/01 either (1) 250 feet from the waste disposal area, or (2) 50 feet within the property boundary, whichever is closest to the waste disposal area. An exceedance of Groundwater Quality Standards at or beyond the Compliance Boundary is subject to immediate remediation action according to 15A NCAC 2L .0106(d)(2). b. The REVIEW BOUNDARY is established around the disposal systems midway between the Compliance Boundary and the perimeter of the waste disposal area. Any exceedance of standards at the Review Boundary shall require action in accordance with 15A NCAC 2L .0106(d)(1). 4. Applicable Boundaries a. Any additional groundwater quality monitoring, as deemed necessary by the Division, shall be provided. If there are any questions please call David Goodrich at (919) 715-6162. Attachments: FIGURES 1 & 2. C:/My Documents/ GW01066A.doc Page 4 of 4 Shl Doc 07/01 32'30' 1451 (LITTLE KINNAKEET) 45Z -ell (E);L F-0-1-11,41 "10 20' H I lmOf{� l• 1 _. {� NOTES. I. MONNTORNG HELL SHALL BE CONSTRI-CrI D SUCH THAT THE HATER LEVEL IN THE WELL 15 NEVER ABOVE OR BELOW THE , 'Ht •" SCREEN PORTION OF THE FELL AT ANY TIME. CURVE TABLE S 2. ALL HIM5 THAT ARE CONSTRUCTED FOR PURPOSES OF - L GROUNDWATER MONITORING SHALL BE CONSTRUCTED IN 7 I 1 I 1 4 11 t I P G A• SL I21 i B Z U ACCORDANCE WITH BA NLAC 2C.0106 (6TANDARD3 OF M0� a IUUOL7 \ 1 ;,•','✓ N D. GRAY CONSTRUCTION FOR WELLS OTHER THAN WATER SUPPLY) AND � � D�DK PQ 306 SITE . ANY STATE LOCAL. LAWS AND REGULATIONS PERTAINING TO Ha„ CONSTRICTION. 1 M I 5. NCD1DM SHALL BE NOTIFIED 45 HOURS PRIOR TO THE E<R N7332- 58` CONSTRUCTION OF ANY MONITORING WELL so AN RtSPBCTION CAN BE MADE OF THE MONITORING WELL LOCATION. SLX34 N �6� • \ ' ' R' _ NOTIFICATION TO THE REGIONAL GIIDUNDFATER SUPERVISOR I 1 :. ( �+ \, AV_Oj=?OEAN.. SHALL BE MADE DURING NORMAL OFFICE FOURS, DXLUDING STATE HOLIDAYS. LY �. NDp j3.2'iE — 254. J /- —"ti ` \ OR mar rcINnMAP P A. WITHIN 5DfTY DAYS OF C"LETION OF ALL MONITORING �i� N �MD euLDD Y GRAY SA HELLO, THE PERMITTER SHALL SUBMIT 2 ORIGL COPIES OF um / r Da 1078. P0. NO A SCALED TOFOGRAPHC MAP (SCALE NO GREATER THAN I" W) SCJNED AND SEALED BY A PROFE3510NAL 19r-INFER Q' yT OR LI A STATE CE7NSED LAND SURVEYOR THAT INDICATES ALL , ® / Of THE FOLLOhIING ItNFORMIATOW X ]hoc M / LOCKING CAP� Nw-i L A. THEON LOCATION AND rDENTITY OF EACH MONIING TORWELL WA6 WATER TREATMENT LANT 1 -•� \ CASING . 125 ACRES NI rl Ell B. THE LOCATION OF THE PASTE D1ST'0UN SYSTEM 549.W SO.FT. j /M / . C. THE LOCATION OF ALL PROPERTY BOUNDARIES - _ 1 ® A�DW or ULI . D. THE LATITUDE AND LONGITUDE Q THE ESTABLISHED I . HORIZONTAL CONTROL MONtJMEMCf I 1 YALM/H1r Prt1K � LS'-2 E. THE REL.ATNE ELEVATION OF THE TOP OF THE WELL I 1 / EXISTING AD11 r� CASwG , I ' tY ,-->r I CASING F. THE DW-TH OF THE WATER BELOW THE MEASURING POINT. 1 AT THE TM THE ' POINT I6 EST "54M ��` Q-OIt�LARl21l DNA. NOW OR rmoar S. HITHIN 50 DAYS OF COMPL11IT10H OF ALL HELL '�"_' �U- ^�� • - � - • ' � i � "t WKE NUT CD'Lprr GIIOUT CONSTRUCTION ACTIVITIES, A CFRTW1GATtoN mtfrr BS I Y .`•� - . ��i ��• a`µ, Da 1071L PG. t90 ►� i/� RECENED FROM A PROF15SAONAL ENGIHEIR OR A LICENSED \ I I ` �: - `` .. H �; I :i I� I 0 I . GEOLOGIST CDITIFYDIG THIN AT THE MONITORING WELLS ARE `I I ir``...�``._ ^_r. ,1''I.', I'ntn-am �RT01QTE LOCATED AND CONSTRUCTED IN ACCORDANCE WITH THE WELL Di - - _`y`'--`R'�= T,It ,�.' ral CONSTRUCTION STANDARDS ( ISA NCAC 21C) AND PW'IT NO. MODDISOSS. THIS CERTWICATION SHOULD BE SUBMITTED WTHN COPES OF THE WRL COMPLETION FORM (GH-1) FOR EACH ` L ', �'•w • N - „_ ; .4y`• 1,• �,� _ DWI .. 'A .. . IRm.L AND MWLm TO THE PERMITS AND COMPLIANCE UHT, ®�� GROUNDWATER SECTtOH W IDriI,NC- j /'lltl L. FOR THE MT LAL SAl'PLNG OF THE WBL• AS SPECIFIID I \. )_ - _ - • - - �'-• - `- .. � '" N�H .. —� \ . ' ;�•� - •y r£�(+�; Els6'SERE W PERMIT IN F100002161, THE PD:1'ITTEE SHALL 1' .�. �••,.• . „, �� ..g�-ri.'gpttgl SUBMLT A COPY OF GH-1 FORM (YELL CO1'1MEnOH FORM) ` 1 1 , .:1 � > , • • � ,,,II, � � (SLOITID PvC) , Z WITH THE COMFI-UNC¢ MONITORING FORM (GW-89) FOR THAT y I ` H'E1L COMPLIANCE MONITORING FORMS THAT DO NOT INCLUDE 1 I .� .�` • �I �„��, � Nora Fm4R7 COPLE5 OF THE GW-I FOR71 HILL Be RETURNED TO THE I 1 ' i :,, FnTTYAN PERMITTU WITHOUT BEING PRISED. FAILURE TO SUBMIT r i D.S. 461. M THESE FORMS HILL RESULT IN THE INITIATION or r I I — � � � � • - QNFORC@MBIT ACTIVITI15 PURSUANT TO NO GENYRAL r 1 - STATUTES t45-215A g 1 �� GROUND WATER MONITORING WELL 7, noNITat HELLS M1H'1-4t-Mf'1-S, SHALL BF 6AMPLm INITIALLY I - - - AFTER AUGUST, AND HOVE I M THEREAFTER WITH ALONG WITH MH-1 N MH-2 FOR THE FOLLOHVAND \ I I Se0.0G' - _ - _ _ _ _ _ -S =_ _ =1_ = - - p WATER LEVEL DH /�,�,� Z _ S11ro734'W g u PALAIIOLO7 5ORV40U TO BE SW I CHLORIDE TOTAL DISSOLVED SOLIDS (TOO) I m 11 • 80.20 a D.B. 616, PQ 696 I• LARGER THAN OUTSIDE ply FECAL COLIFORMS TOTAL ORGAN- COMPOUNDS (TOC)NITRA,Z of CASING. N TOTAL �(�� SULFATTOTAL AnMONU. (o N) W 1 P ', 11 ' $ ll 1C" Ila 2. CENTERED W OOREFIOTO e4 O TH[ RESULTS OF THE SAIFUNG AND ANALYSIS MUST BE g J N . ULD MOONITOEn REC�RING. C MPLIAORM ANNCeE REPORT ) e � �vl Iln p I 1, NDr a Mo1NaLLr11 s Jog 11 m 5• NraOT Z59 . OF bw HISCREEN GH GROUNDWATER SECTION, PERMITS AND CaVLWrA UNIT. Q i1 LILLEY I e=� I S� I SEASONAL WATER LEVEL. I Da tn, M 37, , IL 1 HI s 111 1 , ❑ , ,1 4. CASING AND SCTRSW MATERIAL 6. ANY ADDITIONAL GROUNDWATER QUALITY MONITORING, AS I TO SE 6CK ti PVC. DEEMED 5Y THE DIVISION, SHALL BE PROVIDED. ��1 6. H(LL HEAD To as LAww mD 1. THE COMPLIANCE BOUNDARY FOR THE DISPOSAL SYSTEM , , i, LEGEND WITH HIGHLY VIBIB" WARNING ECI-. AS SPECIFIED BY REGULIN ATIONS 15A HCAC 2L ARE. SAYING. 'WELL IS FOR (1) 2W FEET FROM THE WASTE DISPOSAL AREA OR I �' 1 II (2) 60 FEET WITHIN THE THE PROPERTY BOUNDARY,- WHICHEVER IS CLOSEST TO THE WASTE DISPOSAL AREA. —'T------- :ITN "II 1 9 t I 1 I I a F011mr RDA. 1110Y 4. MRT CJ-I k 11 �,11 I ;,I 1 �,1 1 i11 1 MONITORING AND NOT CAPERED SAFE FOR ORIACNG'. /.. A. HELL TO BE AFFORDED £ REASfNAB" PROTECTION 4:• FIGURE 2 OUTER BANKS - KINNAKEEI' SHORES ROTARY DISTRIBUTOR SYSTEM DARE COUNTY WQQN9 M4 jQXW66 . SITE DETAIL MAP