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h , SECOND QUARTER,2002 GROUNDWATER MONITORING REPORT JAMAR OIL DISTRIBUTION AUGUST 2002 Summary of Previous Investigations In 1995, a 300 gallon waste oil UST and a 500 gallon kerosene UST were excavated and removed from the site No environmental issues were documented with the removal of these tanks In December 1998 two 6,000 gallon and one 10,000 gallon gasoline USTs were excavated and removed from the site and replaced with a two compartment 20,000 gallon UST meeting EPA and State of California upgrade requirements Soil samples taken in conjunction with the tank removal contained detectable concentrations of petroleum hydrocarbons and on January 27, 1999, an Unauthorized Release form was filed with the County An additional Unauthorized Release was filed with the Country on June 11, 1999 In response to a directive from the County,John P Cummings &Associates (JPCA) conducted a subsurface investigation on September 8-9, 1999, by installing and sampling three monitoring wells(MW-1,MW-2,and MW-3) MW-1,MW-2, and MW-3 were drilled to approximately 78 feet bgs,74 feet bgs,and 74 feet bgs,respectively and sampled every 5 feet Groundwater samples were collected from the three wells on September 23, 1999 • On August 21,2000,JPCA did a further subsurface investigation by drilling and sampling one soil boring(B1) and installing and sampling two additional monitoring wells (MW-4 and MW-5) The soil boring was drilled to approximately 115 feet bgs and sampled every 5 feet MW-4 and MW-5 were drilled to approximately 75 feet bgs with soil samples collected every 5 feet Groundwater samples were collected from MW-1,MW-2,MW-3,MW-4 and MW-5 on August 30, 2000. The results of this investigation are documented in JPCA's 2"d Phase II Environmental Assessment Report dated October 25, 2000 GHH assumed environmental consultmg responsibilities for the site in July 2001 In April 2002, GHH Submitted an Additional Assessment Workplan m response to County directives for additional investigation at the site The County approved the workplan in a letter dated May 28,2002 SCOPE OF WORK Groundwater monitoring and sampling activities were conducted at the site on June 11, 2002. The following is a brief summary of the scope of work authorized by JAMAR. Measure depths to groundwater in monitoring wells MW-1 through MW-5 Purge a minimum of three equivalent well volumes of groundwater from each of the . wells and monitor for pH,temperature and conductivity Collect groundwater samples from the monitoring wells 2