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Work Plan for Monitor Well Cloa.., c and Monitor Well Installation Canepa's (Pacific) Car Wash Page 2 description of the proposed groundwater extraction and treatment system to be installed. Condor is currently conducting planning and permitting activities and modification of the current site treatment system (soil vapor extraction) in anticipation of the final remedial design and implementation at the site. The balance of this work plan describes the proper closure of MW-8 and the installation of the additional proposed off-site, down-gradient monitor well (MW- 13). The proposed location for MW43 is shown in Figure 2, attached. The closure of MW-8 and installation of MW-13 are proposed to be conducted by V&W Drilling of Isleton, California (V&W, License # C57- 720904), under the supervision of a Condor registered geologist. A monitor well closure permit application and a monitor well installation permit application have been prepared by Condor and are attached to this work plan. Application fees will be forwarded promptly under separate cover. Because the proposed location of MW- 13 is in the City of Stockton (City) right-of-way, however, the City will require an encroachment permit, including a Revocable Permit to include a Lien Bond and insurance provisions provided by the Client/owner, Mr, Remo Canepa. Condor is currently preparing the encroachment and revocable permit applications and will facilitate the bond and insurance provisions. Condor understands that the attached well installation permit application is not complete until the encroachment permit process is complete. Upon receipt of the required permits, Condor will schedule and coordinate the fieldwork. The SJCE14D and the City of Stockton will be notified at least 48 hours in advance of the fieldwork. Prior to initiating the fieldwork, the proposed monitor well location will be marked with white paint and Underground Service Alert will be notified at least 72 hours in advance of the fieldwork to locate and identify underground utilities in the vicinity of the work area. In addition, a tailgate safety meeting will be held and a site-specific Health and Safety Plan will be discussed with, and presented to, all field personnel for their signatures. Monitor Well Destruction Monitor well MW-8 was drilled by Weeks Drilling in 1994. Weeks Drilling used hollow stem auger with an 8-inch O.D. drill bit to construct the well with two-inch schedule 40 PVC piping to a depth of approximately 65 feet below ground surface (bgs). MW-8 was screened with 0.020 slotted PVC from approximately 45 to 65 feet bgs. MW-8 will be destroyed in accordance with the provisions of the SJCEHD and City of Stockton permits. The monitor well will be destroyed by pressure grouting it from the bottom up, by first inserting a tremie into the well bore and displacing the well water with a cement/bentonite (3 -5%) grout. Thirty-five pounds per square inch of pressure will be used to inject the grout. Once the grout is in place, the upper portion (5-feet) of the well will be drilled out and the grout will be leveled and brought to grade. The traffic box and any other refuse will be removed from the site. Grout volume calculations for the closure of MW-8 are shown in Table 1 , on page 5 . The volume of grout is based on the diameter of the borehole and the PVC casing, the length of the PVC casing and filter pack, and an estimated filter pack porosity of 0.25 . Monitor Well Installation Monitor well MW- 13 will be installed in accordance with the provisions of the SJCEBD and City of Stockton permits. MW-13 will be installed by the hollow stem auger method, using an 8-5/8- inch O.D. drill bit to a depth of approximately 45 feet bgs. The monitor well will be constructed with 2-inch O.D ., Schedule 40, flush-threaded, machine-slotted PVC screen (slot size 0. 010) extending from a depth of approximately 25 feet to 45 feet bgs. A flush-threaded PVC bottom cap ow %' a CONDOR