ARCHIVED REPORTS_XR0002938 - Laserfiche WebLink

Home Browse Search

`mss S E C 0 R �j . Ms Victoria McCartney March 24, 2005 Page 5 3 To replace interim groundwater batch extraction at the site and to prevent further off-site migration of MtBE and TBA, SECOR supervised the Installation of 10 ozone sparge (OS) wells in March and April 2004, and completed the Installation of an OS system in April and May 2004 The OS system consists of a KVA C-spargeTM1° panel, a ten-point injection manifold, and burled 318-inch diameter, and high density polyethylene (HPDE) system lines contained in 2 to 6-Inch diameter PVC conduits Each point on the injection manifold is equipped with an electrical solenoid, which controls the flow of ozone/air mixture to the OS wells The solenoids are controlled by a timer, which is programmed to sequentially inject into each well for 7 minutes (70 minutes total for each cycle), 18 times a day (18 cycles per day) The sparge panel is equipped to with a compressor rated to deliver 6 standard cubic feet per minute at 10 pounds per square Inch (psi) The OS system was brought on-line on May 25, 2004 (SECOR, 2004) SCOPE OF WORK On January 18, 2005, SECOR oversaw the installation of two off-site groundwater monitoring wells (MW-11 and MWA2) at the locations shown on Figure 2 Drilling activities were performed by Cascade Drilling Inc (Cascade) of Rancho Cordova, California The completed scope of work is summarized below • Health and Safety. As required by the Occupational Health and Safety Administration (OSHA) Standard "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), SECOR prepared a } site-specific Health and Safety Plan (HASP) Prior to the commencement of fieldwork, the HASP was updated with appropriate field personnel and subcontractor information The field staff and contractors reviewed the HASP before beginning field operations at the site • Permits. Prior to conducting field work, SECOR obtained an encroachment permit from the City of Stockton Public Works Department (CSPWD) for installing the wells, which will be located in the city right of way along West Hammer Lane (MW-11) and Kelley Drive (MW-12) SECOR also obtained well construction permits from the SJCEHD Copies of the permits are included in Attachment 2 • Monitoring Well Installation The exploratory borings for off-site groundwater monitoring wells MW-11 and MW-12 were drilled to depths of 30 feet bgs using hollow stem auger drilling equipment The monitoring wells were constructed with two-inch diameter, schedule 40 polyvinyl chloride (PVC) casings with 20 feet of 0 020-inch slotted screen material The work was conducted in accordance withx stipulations of permits obtained from the SJCEHD and the CSPWD SECOR's procedures for installing the wells are presented In Attachment 3 Boring and well construction details are included in Table 1 and Attachment 4 t I IConocoPhiIhpslRetad Sites1111931Reports111193 Off-Site well Install 1-05 doc SECOR International Incorporated