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

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40 Ms. Angela Lee Humbrook Holdings,LLC February 12, 2014 to Page 9 After further discussions with the CVRWQCB, RDM was directed to attempt to advance the boring until groundwater or refusal was encountered with a limited access Geoprobe drill rig. • On November 5, 2013, RDM supervised the further advancement of soil boring RDM-1. The boring was advanced by Environmental Control Associates of Aptos, California, using a track-mounted, Geoprobe Model 54LT limited access, hydraulic direct-push rig equipped with a 2.25-inch diameter MacroCore sampling device. This specialized rig was utilized because the only access to the borehole location was through a standard 36-inch wide door opening in the former station building (property owner decided not to demolish the building as was previously planned). • Soil boring RDM-1 was advanced to a depth of 48.5 fogs where refusal was encountered due to the drill rig's capabilities, combined with lithologic conditions. Soil samples were collected continuously beginning at approximately 15 fbgs. A portion of each soil sample was placed in a re-sealable plastic bag and field screened for the presence of petroleum hydrocarbons. After the vapors in the soil samples • were allowed to equilibrate with the air in the headspace of the bag, the organic vapors within the headspace were measured using a PID equipped with a 10.6 electron volt lamp. The field PID readings were recorded on the boring log. Soil samples were classified using the Unified Soil Classification System visual manual method and the data was recorded on the soil boring log. Copies of the boring logs are included in Enclosure F. • The lithology encountered in soil boring RDM-1 consisted of silt (ML) and clay (CL) to a depth of approximately 46 fogs and silty sand(SM)to the total depth drilled (48.5 fogs). Groundwater was not encountered in soil boring RDM-1. ECA attempted to collect a groundwater sample by advancing a hydropunch sampling device to a depth of 52 fbgs where refusal was encountered. The hydropunch was then retracted to expose the screened section from 48 to 52 fbgs. After waiting 30 minutes, no groundwater had entered the hydropunch sampling device, so RDM instructed ECA to terminate the • boring. Immediately following drilling, soil boring RDM-1 was backfilled with neat cement grout mixed and placed in accordance with SJCEHD requirements and the California Department of Water Resources Well Standards(Bulletin 74-81). A SJCEHD representative was onsite to observe the grouting. L Ten soil samples collected from soil boring RDM-1 were submitted to Kiff Analytical laboratory (Califomia-certified NELAP#08263CA),in Davis, California,for analysis of: • BTEX, TPHg, fuel oxygenates (MTBE, TAME, DIPE, TBA, and ETBE), lead scavengers (1,2 DCA and EDB), naphthalene, and chlorinated VOCs (full list) by EPA Method 8260 B; and, • TPHd by EPA Method 8015 Modified with and without silica gel cleanup (if TPHd was reported in initial sample); silica gel cleanup was performed using EPA Method 3630C Modified; The laboratory analytical results are summarized in Table 1 and a copy of the laboratory analytical • report with chain-of-custody documentation is included in Enclosure G. Tetrachloroethene (PCE) and TCE were non-detect in all the soil samples analyzed. Petroleum hydrocarbon constituents were non-detect for all analytes in the samples collected at 2.5, 5, 10 and 15 fbgs from RDM-1, with the exception of TPHd, which was reported at concentrations ranging from 3.8 to 5.2 mg/kg following silica gel cleanup. Petroleum hydrocarbon constituents were however reported