WORK PLANS - Laserfiche WebLink

Home Browse Search

S ECOR -�- -- --- - - - Work Plan for Monitoring Well Installation July 31, 2007 Former ARCO Service Station No. 4932 Stockton, California Page 6 groundwater aquifer is unconfined. No confining layers have been encountered in soil borings advanced at the site. Wells have been installed in two zones at the site (depth-to-groundwater is similar in wells installed in both zones): • A zone monitoring wells (MW-1 through MW-11) have been installed to depths of 40 feet bgs. • B zone monitoring wells (DMW- through DMW-3) have been installed at the site to depths ranging from 80 to 82 feet bgs with well screens 5 feet in length. B monitoring zone wells have been installed in the sand and silty sand generally present at 80 feet bgs. PROPOSED SCOPE OF WORK The proposed scope of work for this work plan includes the installation and development of seven groundwater monitoring wells (DMW-4, DMW-5, DMW-6, DMW-7, DMW-8, DMW-9, and DMW-10). The locations of the monitoring wells were selected as an effort to characterize the B' zone in the up-gradient, cross-gradient, and down-gradient locations (Figure 2). SITE HEALTH AND SAFETY PLAN As required by the Occupational Health and Safety Administration (OSHA) "Hazardous Waste Operations and Emergency Response" guidelines (29 CFR 1910.120), and by California Occupational Health and Safety Administration (Cal-OSHA) "Hazardous Waste Operations and Emergency Response" guidelines (CCR Title 8, Section 5192), the contractor will prepare a site specific Health and Safety Plan (HASP). At a minimum, the HASP will define the proposed subsurface investigation activities, describe physical and chemical hazards that may be associated with the work, provide a map to the nearest emergency medical facility, and include material safety data sheets (MSDS) for any hazardous chemicals that will be used or produced during the work. A copy of the HASP will be available on-site at all times during field work. The field staff and contractors performing field activities will review the HASP prior to beginning field operations, as described in this work plan, at the site. WELL INSTALLATION AND SAMPLING Task 1 - Preliminary Field Activities All boring locations will be marked with white paint and Underground Service Alert (USA) will be notified at least 48 hours in advance of drilling, to allow the local underground utility companies to identify the location of any utilities in the area. USA will be notified to identify any public utility alignments that may be in conflict with the proposed borings. In conjunction with the USA, 811 will be notified at least 48 hours in advance of drilling, to allow the local underground utility companies to identify the location of any utilities in the area. The new 811 number is a national "Call Before You Dig" phone number designated by the FCC to eliminate the confusion of multiple "Call Before You Dig" numbers. 811 calls will be directed to the local One Call Center and the affected utilities, who will then mark underground lines. In conjunction with USA and 811, a private utility locating company will be utilized for clearing proposed boring locations for underground utilities. If necessary, an access agreement will be secured from the current property owner or county or city agency prior to starting any field work. 4932 WP for MW Installation 2007.doc SECOR International Incorporated