vvEPA United States Environmental Protection Agency Office of Solid Waste and Emergency Response DIRECTIVE NUMBER: 9481.02(85) Ground-Water Monitoring above the Uppermost Aquifei APPROVAL DATE: 4;8-85 EFFECTIVE DATE: ^r8-85 c . _ ORIGINATING OFFICE: °ffice of Solid Waste 0 FINAL D DRAFT [ ] .A- Pending'OMB approval. STATUS [ ]~ ,B-£.Pending AA-OSWER approval-"" [- ] ;c~:For- review.&/or comment [ ]! l®~Jj-n_ ^envelopment ^ or'; circulating -, — -—-,-.,-»>«- .• ^ . — T- -headquarters'-;-- REFERENCE (other documents]: OSWER OSWER OSWER fE DIRECTIVE DIRECTIVE ------- PARTS 264-265 SUBPART F - GROUND-WATER PROTECTION DOC: 9481.02(85) Key Words: Ground-Wacer Monitoring, Aquifer Regulations: Subject: Ground-Water Monitoring above the Uppermost Aquifer Addressee: Hazardous Waste Management Division Director Regions I - X Originator: John H. Skinner, Director Office of Solid Waste (WH-562) Source Doc : 9481.02(85) Date: 4-8-85 Summary: This memo discusses ground-water monitoring in non-aquifer saturated zones, ------- 9i3L.02 (85) APR 8 198F MZMORAMDCM SOBJKCTi Ground-water Monitoring Above the "Uppermost Aquifer* faCHt John £. Skinner/ Director Office of Solid Waste (WH-562) TO: Hazardous Waste Management Division Director legions I - X Office of General Counsel (LE-130) Some hazardous wast* facilities that are subject to the ground-water protection (Subpart F) rules are situated in or above saturated sones that do not meet the customary definition of "aquifer.* In these cases, questions arise as to how to apply the ground-water monitoring regulations which call for aonitoring in the uppermost aquifer. I aa aware that several of you have been and are negotiating with facilities in these situations. For a number of reasons/ EPA. regions/ with encouragement and support fro* OSW, have been requesting applicants for RCRA Part B permits to provide monitoring in non-aquifer saturated sones. The major reasons aret (1) the intent of the regulations is to monitor the first ground-water contamination, not to link aonitoring to a cosnercially productive aquifer. The preamble to the regulations (33192 PR/ Hay 19, 1980) states "The monitoring program seeks to detect contamination of the uppermost aquifer because that will be the first ground water affected by a leaking disposal facility!" (2) such monitoring provides early warning on the performance of liner and leachate collection and removal systems, since the flow of contaainants to the uppermost aquifer and subsequently to monitoring wells in the aquifer may take many tens or even hundreds of years; and (3) such monitoring provides essential information on the direction and concentration of the flow of contaainants from hazardous waste units since formations with low permeability (e.g./ aquitards and aquicludes) nay divert the flow of contaainants to surface water/ upgradient wells, or beyond downgradient wells so that the contaminants are not dis- cernable in the aquifer monitoring wells at the waste boundary. BApril:vh:Vra-565E:rro2102M:382-4658:03/15/85:dsM3 ------- On January 30, 1935, Z discussed this issue at a meeting with the national Solid Wastes Management Association (asHMA). HSWIA agreed that such information is useful and proposed that guidance be developed by OSM. To assist us, 3S33HA developed a proposed draft of that guidance (the guidance and SStCMA cover letter are attached). 91ease review this proposal and transmit your comments by April 29 to Bob April, of ay staff, at mail code MB-5651, electronic mail bos BMS301. Tou may also wish to discuss this issue with State authorities. The MSttMA proposal is more of a policy statement than a guidance. Z am interested in your comments on the need for such a statement or guidance, the scope and content of the guidance, and the desirability of regulatory amendments. Thank you for your cooperation. Zf you have aay questions, please telephone me (332-4*27) or Bob April (382-4654). Attachment - ------- |