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On 8 December, the State Board issued interim guidance in a memo <br /> requesting that cleanup oversight agencies "proceed aggrewAvely to <br /> close low risk soil only cases", and where "low risk ground water" is <br /> ' imparted, 'that active remediation be replaced with monitoring to <br /> determwe if the mel leak plume a stable.' <br /> It is Lrnportant to understand that the sites used to develop the rec- <br /> r emmendations in the Lawrcace Livermore report were single, non <br /> commingled, plumes in alluvial soils. Therefore, the report recom. <br /> mendations do not:apply to sites in fractured rock or cobble/sand <br /> areas. State Board and Lawrence Livermore staff have repeatedly <br /> stated the qualification in training sessions and at the SS 1764 corn- <br /> tnittee meetings. However, the distinction between alluvial sails and <br /> fractured rock or cobble and sand lithology was omitted from the <br /> LLNL Report, <br /> Letters have been sent out from the Cleanup Fund stating that the <br /> fund only will pay for pump and treat remediation where the effec- <br /> tiveness can be demonstrated. Pump and treat,although effective in <br /> fractured rock,cobble and sand as a single treatment process, is used <br /> to control plume migration it conjunction with other measures such <br /> as soft vapor extraction. Staff Is meeting with ether Regional Board <br /> staffs in mid January 1996 to discuss a consistent procedure for <br /> implementing the 8 December memo. A copy of the discussion <br /> memo we sent to the other regions and a possible letter to send to <br /> owners of probable low risk sites are attached. <br /> page 2 <br />