oEPA United States Environmental Protection Agency Office of Solid Waste and Emergency Response DIRECTIVE NUMBER: 9523.05(84) TITLE; Ground-Water Monitoring Requirements at a Site Overlying by Two Aquifers APPROVAL DATE. 9-6-84 EFFECTIVE DATE: 9-6'8A ORIGINATING OFFICE: office of solid waste E FINAL * ^ ^ D DRAFT STATUS: A- Pending OMB approval B- Pending AA-OSWER approval C- For review &/or comment [ ] D- In development or circulating REFERENCE (other document!): headquarters OSWER OSWER OSWER VE DIRECTIVE DIRECTIVE Dl ------- PART 270 SUBPART B - PERMIT APPLICATION DOC: 9523.05(84) Key Words: Regulations: Subject: Addressee: Originator: Source Doc: Date: Summary: Acquifer, Enforcement 40 CFR 270.14(c), 264.222, 265.91(a) Ground-Water Monitoring Requirements at a Site Overlying by Two Aquifers James Reidy, Chief, RCRA Permits Section, Region II Rich Steimle, HQ Permit Assistance Team (Steam Team Comments Re: Phillips EGG) #9523.05(84) 9-6-84 According to §270.14(c), the permit applicant must characterize the upper- most aquifer, describe any existing contamination, and provide all information- necessary to establish an appropriate ground-water monitoring program in the permit. If there are two aquifers, a shallow upper till aquifer which transmits ground water only 2-3 months per year and is dry the remaining months, and a deeper bedrock aquifer which is recharged by the upper aquifer at the Downgra- dient Point of Compliance (POC), both aquifers should be monitored. When the upper aquifer dries out, monitoring should continue in the lower aquifer. A condensed sampling program should be used in the upper aquifer and less frequent sampling in the lower aquifer. The applicant's alternative to such a comprehen- sive monitoring program is a double liner system as provided in §264.222. If the applicant is in violation of §265.91(a), the Region can use a com- pliance order under RCRA §3008. If the applicant is also in violation of §270.14(c), the Region should issue a Notice of Deficiency and Warning Letter to enforce a time schedule for each phase of the investigation. .The Steam Team does not recommend issuing short-term permits when the applicant fails to provide sufficient information to meet the Part B require- ments. ------- 9523.05 (84) SEP 6 1984 MEMORANDUM Subject: Steam Team Comments re: Phillips E.C.G. From: Rich Steimle HQ Permit Assistance Team To: Jares Reidy, Chief . RCRA Pernits Section, Reg. II * Background - Phillips, E.C.G. Inc. has applied for a RCRA permit to continue operating two impoundments at Seneca Falls, N.Y. One impoundment accepts industrial wastewaters and the other accepts dewatered wastewater treatment sludge. Both wastes are hazardous because of EP Toxicity for lead. The site is underlain by two aquifers: a shallow internit- tend aquifer in glacial till and a deeper aquifer found in shale bedrock. Separation is by 40' to 80' of bedrock. The shallow aquifer only transmits water during the wet spring season; during the remaining period of the year monitoring wells are dry. This aquifer also recharges the deeper bedrock aquifer, through an area which is highly fractured. This recharge zone is at the downgradient Point of Compliance (POC). The applicant has attempted to define the qualitative and quantitative nature of the local groundwater; however, the mixing of aquifers at the POC has caused confusion over which aquifers to monitor and when. Issue - Region II specifically asked: 1.) How much groundwater monitoring data is necessary for permitting? * 2.) What options are'available for accelerating the gathering of new ground water monitoring data? 3.) Can & short term permit be issued with a ground water monitoring compliance schedule? ------- Discussion - Grcundwater monitoring data requirements for RCRA permit applicants are outlined in §270.l4(c). In essence, the permit applicant nust characterize the uppermost aquifer, describe any existing coritanination, and provide a,ll information necessary to establish an appropriate groundwater monitoring program in the permit. The applicant in this case has not adequately defined th» nature of the uppermost aquifer or proposed an appropriate i^roundwater nonitoring system. The applicant's consultant has suggested that the shallow aquifer he monitored upgrartient of the site for background data arib the deeper aquifer be monitored at the downgradient POC. We feel that monitoring two different aquifers for comparison purposes is an uneound technical proposal since the water quality in each is naturally different. However, we feel that a reliable groundwater monitoring system can be installed providing certain assumptions are proven. The upper till aquifer transmits ground water 2-3 months per year and during that period it should be considered the uppemost aquifer. Upgradient background samples from this aquifer can easily be obtained. Downgradient water quality at ths POC nay be*obtained from wells installed in the frac- tured bedrock above the lower aquifer. Statistical comparisions should he made on these samples taken during the 2-3 nonth period described above. When wells in the upper aquifer dry out, nonitoring should continue in the lower aquifer. Even though the upper aquifer coases to recharge the lower aquifer, potential seepage from leakage in the lagoons nay continue to percolate through the fractured bedrock and affect th» quality of the lower aquifer. wells installed in the bedrock aquifer near the Ingoons should be considered ns downgradient monitoring points. Background sampling points can be-located east and west of the lagoon, parallel to the Senoca River and out of the zone of potential leakage. Since flow in the upper aquifer iy brief and the system is very dynanic, a condensed sampling program should be used. We suggest 2 to 3 downgradiont wells, 2 upgradient wella, and a sampling frequency of twice a month. In the deeper aquifer, sampling need not be as frequent; however, 2 to 3 downgradient wells and the same nuraber of upgradient wells should be installed. The suggested rnonitoring system is complicated and con- tingent upon many assumptions which the applicant has not com- pletely substantiated. The applicant may continue to obtain data to develop hydrogeologic models so that the suggested or a similar grounrtwater nonitoring system may be installed. How- ever, the applicant must be aware that since the loc«l ground- water systen is complicated, an abnormally large amount of data -2- ------- ' ' is necessary to justify any theoretical models. Also, the applicant should be required to submit more data then a similar facility monitoring one aquifer. ' We suggest that the hydrogeologic description be complete by .Spring, 1985. This is ample tine to install additional wells/ establish background quality in the upper and lower aquifer, develop a dependable flow model, and determine whether groundwater contamination is occuring, as required in 5270.14{c). The level of study during this period should be very condensed ^ with very frequent sampling and ground water level measurements. The consultant should review the data as received to make any changes or modifications in the investigation. Since the .applicant is in violation of 265.91(a), the Region has the option of using a compliance order under RCRA 3003 since the applicant is also ..-.." in violation of §270.14(c), the Region should issue a Notice of Deficiency and Warning Letter to enforce a time schedule for each phase of the investigation. Guidance on1this procedure can be found in the September 9, 1983 memorandum from Lee Thomas on , late and incomplete Part B Applications, .. ; - * v-v The applicant should be advised that an alternative to such a comprehensive monitoring!program is a double lined system as provided in $264.222. . We do not recommend issuing short term permits when the applicant has not provided basic information to meet the Part B requirements. This information must be provided through the Part B process so that appropriate permit conditions can be . drafted. The best mechanisms to address this need, as suggested above, are a clear indication to the applicant of Part B deficiencies and a compliance order to establish a time period for the submission of information. . Recommendations - Advise Region II that> . 1.) The applicant has not adequately defined the ground- water flow direction or groundwater quality. 2.) A comprehensive, concise groundwater investigation should be conducted through t;he Part B process . to support the'location of groundwater monitoring wells and delineate any plume of contamination if it exists. This .investigation should conclude by June 1985. Contacts .'.'.' , , .:. ________ . . w. »... . . . , ' * ' '' " ' Andrew Bellina * Rich Steimle - WH-563 U.S. EPA Region II ' . . U.S. EPA Air and Waste Management Division .Permits and State Programs Division 26 Federal Plaza . 401 M St. SW New York, N.Y.10278 - Washington, D.C. 20460 FTS 264-0548 . , 'PTS 382-4754 ------- |