ARCHIVED REPORTS_REPORT SUMMARIZING INSTALL OF MONITORING WELLS MW4,MW5,MW7,MW8 & SOIL BORING RDM1 & 4TH QTR 2013 GROUNDWATER SAMPLING

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• Ms. Angela Lee Huntbrook Holdings,LLC February 12, 2014 Page 7 other required tasks. RDM has retained the soil samples and they can be submitted for analysis at a future date if it's determined to be necessary for closure. • Groundwater Monitoring Well Construction The monitoring wells were each constructed of 2-inch diameter, flush-threaded, Schedule 40 PVC casing, installed to a depth of 65 fogs (60 fbgs for monitoring MW-8). The wells were screened over the lower most 20 feet (15 feet for MW-8) with 0.010-inch, machine-slotted Schedule 40 PVC casing. The annular space was filled with No. 2/12 silica sand to approximately 2-foot above the top of screen section. A 5-foot thick transition seal of bentonite(Puregold®Medium Chips)was emplaced above the filter pack. The bentonite was then allowed to hydrate for a minimum of 30 minutes. On top of the bentonite seal, a neat cement grout sanitary seal was emplaced to within 1-foot of the ground surface. The cement grout was mixed in accordance with the SJCEHD requirements and the California Department of Water Resources Well Standards (Bulletin 74-81). A SJCEHD representative was onsite to observe the grouting of the monitoring wells. The ground surface of each well was completed with an 8-inch diameter, traffic-rated, well box set in concrete. The monitoring well construction details are included in Enclosure F. • Well Development The monitoring wells were developed by RDM on October 16, 2013. The wells were developed by mechanically surging with a surge block and bailing, followed by purging using a submersible pump. During development, physical parameters (temperature, pH and specific conductivity) were monitored and recorded. Copies of the well development field sheets are included in Enclosure H. A total of approximately 95 gallons of groundwater was extracted from the four monitoring wells during development. The water was pumped directly into RDM's 250-gallon poly tank, appropriately labeled as non-hazardous waste with the generator's contact information, and hauled directly to Instrat in Rio Vista, California, for disposal. • Surveying The locations and elevations of the monitoring wells were surveyed on October 16, 2013 by Morrow Surveying, a California-licensed land surveyor, from West Sacramento, California in accordance with California State Water Resources Control Board's GeoTracker Survey_XYZ electronic deliverable format. A copy of Morrow Surveying's report data is included in Enclosure I and the results are included in Table 2. • Initial (Fourth Quarter 2013) Groundwater Sampling- Monitoring Wells MW4, MW-6, MW-7 and MW-8 Groundwater monitoring is currently performed at the site on a semi-annual basis during the first (March) and third (June) quarters. Initial groundwater samples were collected from the four newly- installed monitoring wells (MW-4, MW-6, MW-7, and MW-8) during the fourth quarter 2013. On December 3, 2013,RDM measured depth to water in monitoring wells MW-1 through MW-4, MW-6, MW-7 and MW-8. Depth to groundwater in the monitoring wells ranged from 47.58 to 48.80 feet below the top of the well casing (btc). Cumulative groundwater table elevation measurements since the third quarter 2011 are presented in Table 1.