SITE INFORMATION AND CORRESPONDENCE

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GE�2 GENESIS ENGINEERING&REDEVELOPMENT Former Arcady Oil Drilling Mud Disposal Site Inorganic Plume Delineation The Regional Water Quality Control Board ("RWQCB") has requested the extent of an inorganic plume near the Former Arcady Oil Drilling Mud Disposal Facility be assessed(RWQCB Review of Site Investigation Report for the DePaoli/Arcady Oil Property, San Joaquin County, dated April 30, 2009). The initial phase of investigation to assess the lateral extent of the inorganic plume included advancing 11 exploratory borings and collecting and analyzing reconnaissance groundwater samples from the borings. The work was conducted in September 2009,under two San Joaquin County permits, Permit#SR 58241 (APN 131-09-122), and Permit#SR 58243 (APN 131-400-08). Based on the findings of that phase of investigation, additional site investigation tasks will be conducted. Additional tasks include installing and sampling two monitoring wells on the Arcady Property to further assess the lateral extent of the inorganic plume at the site. The monitoring wells will be installed to monitor shallow groundwater conditions, north and south of existing monitoring well MW-5. The proposed monitoring well locations are shown on the attached figure. These wells will be installed the former Arcady Oil property(APN 131-09-122). The boreholes for the monitoring wells will be advanced using a track mounted hollow-stem auger drill. The anticipated depth of the monitoring wells is 25 feet, depending on what depth groundwater is encountered. The monitoring wells will be constructed of 2-inch diameter flush- threaded, Schedule 40 PVC casing with 0.010-inch factory-slotted screen. A ten foot well screen will be placed at the bottom of each boring. Monterey 2/16 sand pack will be placed in the annular space across the entire screen interval, and extend approximately 2-feet above the top of the well screen. A 2-foot bentonite transition seal will be placed above the sand pack, and a Portland cement seal will extend from the top of the bentonite seal to the ground surface. The wells will be completed with above ground well monuments and protective steel bollards.