Laserfiche WebLink
from Leaking UST" dated April 25, 1994., prepared by Wm. J. Hunter <br /> & Associates . <br /> June, 1994 7 First quarterly monitoring revealed the presence of <br /> BTEX & TPH-G in MW-2.; levels were lower than first recorded. <br /> MW-2 & MW-3 still below detection levels . Gradient still to the <br /> north. <br /> September, 1994 - -Second quarterly monitoring measured continued <br /> lower levels of BTEX; however, TPH-G :had increased significantly. <br /> MW-2 & MW-3 still below detection limits . Hydraulic gradient has <br /> shifted about 40 degrees to the northeast . <br /> December, 1994 - Site of removed UST was reentered and approxi- <br /> mately 108 cubic yards of soil was removed. Field observation <br /> and results of laboratory analyzes revealed that some contami- <br /> nated soil remained. <br /> March, 1995 - Results of the fourth quarterly groundwater <br /> monitoring showed that the hydraulic gradient is still to the <br /> north, and only MW-•2 revealed -any contamination. <br /> WORKPLAN FOR SOIL & GROUNDWATER INVESTIGATION: <br /> Because the water table is less than 10 ' bgl based on the March, <br /> 1995 sampling event, we plan on accomplishing the work by either <br /> hand-augering, or driving small diameter probes with a portable ' <br /> power unit . RFP' s will be prepared and sent to qualified <br /> contractors when the workplan has been approved. The work will <br /> be performed as detailed below under the direction of WJH i <br /> personel . <br /> We anticipate doing the work in stages; the first test points <br /> will be located in the approximate locations shown on the <br /> attached EXHIBIT A; they are ddentified by the 6 circled spots <br /> marked with an A. Depending upon the,' results of field screening, <br /> some or all of the test points identified as B-will be placed. <br /> Test points C may also be required if� the plume has migrated that <br /> far. <br /> _ Because of the proximity of buildings, it will be difficult to <br /> place additional test points west ofthe excavation; however it <br /> is possible to work- inside of the two adjacent buildings if <br /> necessary. <br /> BRIEF OUTLINE OF APPROACH TO BE USED IN PLACING TEST POINTS : <br /> 1 . Each test point will be advancedto5 ' below grade using <br /> 3 <br />