Laserfiche WebLink
F <br /> h <br /> V <br /> ®C. gP:1 -*NTO <br /> Addendam to Mr. Haran R6 <br /> November 19, 1990 <br /> Page 2 <br /> (Attachment I) show the borehole locations and the estimated <br /> extent of contamination. <br /> Based upon the finding of the site assessment, Versar <br /> developed a remediation plan for the facility. The plan was <br /> presented in the report entitled °Remediation --;'.'an for the <br /> Pacific Bell Ashley Road Facility (UE-132) l' dated March 8, 1989, <br /> The remediation plan recommended the excavation and <br /> bioremediation of contaminated soil from beneath the former UST <br /> site. <br /> REVISED REMEDIATION PL&N <br /> Since the submission of the remediation plan, the <br /> feasibility of excavation at the site has been re-evaluated. The <br /> former UST site is located directly adjacent to the 'front: of the <br /> 'Icific Bell facility building. Because of the nature„c}.._the <br /> facility activities, it is constructed to withstand' la . k: 3 <br /> magnitude earth tremor,. As a result, the bearing loi.`. •gin the <br /> str.-icture's foundation is significant. .the extensive `_.. ._ovation <br /> proposal would significantly affect. ; -ie structural late4rity of <br /> .✓ the building. Furthermore, the ext'r �;ae cost of shoring for the <br /> excavation of the contaminant plume presents a cost/benefit <br /> feasibility problem. It is therefore necessary to determine if <br /> site remediation can be accomplished without excavation and the <br /> accompanying risk to the integrity of the facility. <br /> Alternate Method of Remediation <br /> The alternate method of remediation proposed for the site is <br /> soil vapor extraction in association with enhanced natural <br /> biodegradation of the contaminants. In order to determine if the <br /> proposed methodology is suitable for the site, a pilot study will <br /> be undertaken. The goals of the pilot study will be to: <br /> 1) More fully define the vertical and lateral extent of <br /> soil contamination at the site. <br /> 2) Determine the suitability of the site for in situ vapor <br /> extraction as a remediation method. <br /> 3) Determine the effectiveness of naturally occurring in <br /> situ biodegradation under conditions of enhanced air <br /> flow. <br /> E - <br />