CORRESPONDENCE_1984-1989 - Laserfiche WebLink

Home Browse Search

,STATE 0!:,r ►WF0RNIA CALIFORNIA REGIONAL WA CENTRAL VALLEY REGION 3443 ROUTIER ROAD RAMENTO, CA 95827-3098 5 March 1987 Mr. Greg Basso Forward Inc. P.O. Box 6336 Stockton, CA 95206 FORWARD LANDFILL SWAT PROPOSAL (CASE NO. 2209) GEORGE DEUKMEJIAN, Governor tE i LJ... -ct EIV4IE ;"' !' Q €_ IIc LTif FER`OviI /SERVICES I have reviewed the Solid Waste Assessment Test (SWAT) Proposal submitted by Beta Associates on 26 January 1987. Certain sections of the document need clarifica- tion 'and I will address those points later on in this letter. Since the SWAT Report due date of 1 July 1987 is rapidly approaching, you may proceed with the plan as long as you respond to my comments before you start work on that partic- ular aspect of the project. I want to observe drilling and installation of the ground water monitoring wells as well as collection of the vadose zone soil cores, so please send me a schedule for these activities as soon as possible. On page 2 of the proposal you mention that a leachate sump access port for Trench 1 will be installed after final grade over the trench is established and that a leachate analysis from that trench will be included in the SWAT Report. Will the final grade be finalized early enough to allow this work to be done by 1 July 1987? Jack McCollough mentioned that he -did not remember if Trench 1 had a leachate collection system or not. I searched our Forward files and found that Trench 1 has a leachate collection system. In a State Water Resources Control Board inspection memo dated 31 March 1978, James Parsons stated that gravel filled drains had been installed in Trench 1. These drains fed a sump at the south end of Trench 1. A five -inch PVC pipe extended from the sump to the ground surface, acting as a leachate sump access port. In a letter from Beta Associates dated 30 April 1982, Jack McCollough said that the riser pipe of Trench 1 was checked to find if there was any leachate in the sump. What happened to the five -inch PVC pipe? How will the Trench 1 sump be located so that a leachate sample can be extracted? On page 6, a statement is made about the inability to make a statistical deter- mination of background values. Although upgradient Well No. 11 is to be replaced, the data gathered from that well in the past can be used to establish background levels for various indicator parameters. These background levels can be modified as information is gathered from the new upgradient wells. Appendix II of Sub- chapter 15 contains a statistical method to be used when the coefficient of variation of a background level parameter is less than 1. If the coefficient of variation exceeds 1, then Appendix II does not have to be used. Background level calculations must be made because the results will be useful in preparing the new waste discharge requirements for Forward.