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N1r.Harlin Knoll Environmental 22 October 2013 Resources Page 3 Management SCOPE OF WORK The scope of work performed consisted of the destruction of the eight existing groundwater monitoring wells at the site. This section presents the procedures followed while performing the scope of work. Permitting and Utility Clearance Prior to implementing destruction activities, ERM secured a permit to complete the scope of work from the County. ERM has included a copy of the County well permit as Attachment A. All proposed well destruction locations were marked prior to performing any destruction activities. Underground Services Alert(USA), a notification service for marking underground utilities on public rights of way,was notified at least 48 hours prior to initiating the proposed work. In addition to notifying USA, a private utilities-locating service was retained to identify detectable underground utilities near all proposed drilling locations to minimize the potential for encountering them during destruction activities. Well Destruction Activities Well destruction activities were performed under ERM's direction on 15 and 16 July 2013. Gregg Drilling and Testing, a licensed C-57 drilling contractor,performed the well destruction activities. Well destruction activities were observed by County Inspector John Yoakum. Each well to be destroyed was measured to total depth to verify,based on original well logs, that significant silting, bridging, or casing failure had not occurred..The wells were destroyed using over-drilling techniques. Prior to drilling, a steel guide rod was inserted in the wells to ensure that the drill stem stayed centered on the well. Hollow-stem augers were used to drill out the grout seal, casing, and filter pack to the depth of the well. The over- drilled borehole was then backfilled with neat cement. The neat cement was emplaced with a tremmie pipe as the augers were removed from the borehole to within approximately 5 feet of the ground surface. At depths less than 5 feet below ground surface, the neat cement was poured directly into the borehole. The surfaces were finished to match the surrounding area.