SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

Mr. Robert Cochran • - 2 - • 14 May 2004 Regional Board and DTSC staff have the following comments on the Work Plan: 1. Page 6 of the Work Plan describes drilling a bleeder hole into the bottom of pipes to determine if there is residual product and to record lower explosive limits (LEL) and oxygen levels. The L&M OU needs to describe how LEL and oxygen levels will be measured through the bleeder hole at the bottom of the pipe if there is residual product. 2. The activities proposed for locating a pipeline along the former Edison Avenue are unclear. The Work Plan states, "The former abandoned pipeline," which indicates the pipeline has already been removed. Based on this, the L&M OU needs to provide further information on whether this work is to confirm whether or not the line has been removed or not, or if there is information that shows that the pipeline still exists along the former Edison Avenue. Furthermore, the L&M OU needs to discuss alternatives to the proposed activities if the pipe ends cannot be determined by the proposed activities. 3. Although the L&M OU is and continues to be proactive in proposing activities to work towards cleanup of the site, the health risk assessment has not been completed and therefore there are not approved health risk cleanup levels established. Furthermore, designated levels for site soils have not been prepared. Therefore, the L&M OU may need to conduct additional sampling based on the confirmation sampling proposed in the Work Plan once cleanup levels for soil have been determined. 4. The L&M OU needs to also notify DTSC of the scheduled assessment work 48 hours prior to drilling the SVE wells. 5. The installation of the SVE wells should not occur until the L&M OU has collected methane pressure readings at the Delta Gateway Apartments. 6. The Work Plan states the L&M OU will submit a report of the SVE well installation and hook up to the SVE system. The Report must include information of the schematics of the hook-up to the SVE system, including flow rates and sampling schedule. As stated, Regional Board staff concurs with the deadline extension and the Additional Assessment Report is due by 29 July 2004. We concur with the Work Plan provided that the L&M OU provides responses to the above comments by 11 June 2004. The Pipeline Removal, Abandonment, and Soil Excavation Report is due by 10 February 2005, as requested in the Work Plan. If you have any questions, you may contact me at (916) 464-4719 or lewisd@rb5s.swrcb.ca.gov. Ljt�t, X_ LU-C,F1 DEVRA LEWIS Environmental Scientist cc: See Page 3