SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

Mr. Steve Pinkerton April 12, 2001 Page 2 DTSC has evaluated the RAO proposed for total petroleum hydrocarbons (TPH). Since fractions of TPH differ in mobility, DTSC recommends RAOs for TPH as motor oil at 1,000 ppm and as diesel at 100 ppm. The Regional Water Quality Control Board concurs that these values should be protective to the waters of the State and are acceptable RAOs. In order to demonstrate that removal of the constitutes of concern has occurred, post excavation sampling will be required. If the sampling indicates that the values exceed the RAOs, additional excavation will be necessary until the objectives have been met. Based on the RAOs and using a plot map, or other maps, the soil areas and depths to be excavated need identification. DTSC anticipates that it will be necessary to reevaluate the cost estimates for excavation, transportation, and disposal of the soil to meet the revised RAOs. DTSC wants to know which disposal facilities could be used and a general period of time for completing the activities. These evaluations must be included in the Feasibility Study or its Addendum. The FS proposes to use a deed restriction to control unacceptable land uses. DTSC requests that the FS provide a brief description of the type of restriction that will be included in the land use covenant. Specifically, the description needs to include prohibited uses including residences, hospitals, schools, and day care centers, and the need for a soil management plan detailing actions to be taken if any contaminated soil needs to be disturbed. Enclosed is a copy of DTSC's policy and procedure (without referenced attachments) for land use covenants. In addition, it is necessary to require the land owners to record the land use covenant, therefore, with any property not owned by the City, DTSC would like affirmation that such parties would accept a land use restriction. Once these comments are adequately addressed, DTSC will be able to provide an approval letter for the Remedial Investigation/Feasibility Study reports. Sincerely, Q rte'. �Y Tga�n Cambridge, Chief Expedited Remedial Action Program Unit Enclosure cc's: See next page.