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f No Furt3wx Acdm Procadurdl .2- a)arcwry 19% In order to close sites,charactenxation is essent,al and the information must be provided ' in a s=mu ry report to determine that no further act#on is required. Closure reports generally include short paragraphs describing applicable dea for each item,bast site reaps,and cumulative informstm tables. Region 5 provides guidance for Tank Owners to investigate,remediate and close tank sites with the publication,updates aced distribution of: i Tri l Board SI#Raarmmcnafations far Preliminary lnmdgatim and EtWuatfon of L&MImnd Tank Sita,including analytical protoaxil, • ApMidf A-P4"ts,fbr report content based on investigations;and, + App+endix B-Cfassaw,data summaries to expedite site closure. We believe the guidance meets the directives of the 6 December memo Muse it allows staff to make a logical conclusion regarding"no further actions'. Attached is a copy of our Appendix B r wJdist which tank owners use to prepare their closure request. In some cases,certain items on the list will not be necessary or applicable,such as a well survey for a soil-o=nly case. Each site closure is based on the particular facts of the case. The goat of restoring beneficial uses of the water resource within a reasonable period of time does riot prevent the Discharger from leaving pollutants in place at the time of closure or relying on passive measures to achieve compliance with water quality objectives. For insunte,the extent and stability of the plume,hydrogeology,laxer ground waiter uses,concentrations remaining,cost of remediation and rationale for dosing the site with the concentrations remaining are all factors to consider. We also consider the carbon chain lengths;the Discharger may leave fuel hydrocarbons in place that exceed Cx at any concentration in soil or ground water due to the low mobility of these large molecules. However,in many cases the first 50 feet of ground water can't be Ignored in the Central Valley and a drinking water well 2M feet away does not always oonstitute a►low-risk ground water site(four instance,local pumpmB gradients must be considered). rIn 1989,after we distributed Appendix A to the Th-RegiorW Recommendations,we found that,relative to the total caseload,we had few site owners(especially of"low-risk" sites)requesting Closure. In 1994,staff distributed our closure documentatiot% requircmenta(Append=B to the Tri-Regional Recommendations)to every LIA in the Region and anyone requesting site closure. In spring 1995,staff were assigned to exclusively implement our closure process. In January 1995,we are placing new staff into the closure section to enable us to increase our ground water closure rate and to close the soil-only cases by reviewing out LUS71S database and contacting the tank owners for site closure information. f � r