ARCHIVED REPORTS_XR0012176 - Laserfiche WebLink

Home Browse Search

Kennedy/Jenks Consultants minimize loss of volatile compounds It is estimated that two to three composite samples will be collected from the soils following aeration All soil samples will be analyzed for Total Volatile Hydrocarbons (TVH, as gasoline) using a modified Method 8015 and BTEX using a direct-purge Method 8020 The analytical methods referred to above conform to EPA Test Methods for Evaluating lid Wa e• Ph sia# hemical Methods (SW846, 2nd Edition) and/or as specified in the Tri-Regional Board Staff Recommendations for Preliminary Investigation and Evaluation of Underground Tank Sites, 30 August 1991 The samples will be analyzed by a California DHS-certified laboratory Detection limits will be set at 0 005 mg/kg for BTEX, and 10 mg/kg for TVH Health and Safety Plan All work performed by Kennedy/Jenks Consultants (K/J) under this workplan will conform to the site-specific health and safety plan (K/J, 1992) and the attached activity-specific health and safety plan addendum (Attachment B) Subcontractors and other personnel not employed by K/J will be provided a copy of K/J's health and safety plan for informational purposes only However, entities or personnel other than K/J shall be solely responsible for their own health and safety protocols On-site safety meetings will be held before work commences to discuss the work to the performed and any safety concerns Soils Disposal Pian • Aeration will continue until soil samples indicate TVH concentrations less than 10 mg/kg and BTEX concentrations less than 0 050 mg/kg for individual components Once the sods have been aerated and sampling has confirmed that: the soils contain concentrations below those levels established above, the sods will be placed into the existing excavation, compacted and paved over Because the fill material will not be impacted by high ground water (highest known groundwater in the area is about 35 feet below ground surface), and the site will be paved to prevent leaching, K/J proposes that residual levels of TVH and BTEX at concentrations of less than or equal to 10 mg/kg and 0 050 mg/kg respectively, ` be allowed to remain in these backfilled soils At these extremely low residual levels, under these site conditions, it is felt that these soils will not pose a threat to the groundwater, and monitoring of the fill area will not be necessary All work will be performed by licensed contractors with appropriate construction permits from the City of Stockton and San Joaquin County Water Disposal Plan As discussed earlier, there are 19 partially filled 55-gallon drums on the site that contain groundwater that was purged from the monitoring wells on the site during development and sampling It is estimated that these 19 drums contain a total volume of about 820 gallons The specific groundwater quality data from each well are found in Table 2 The City of Stockton, Department of Municipal Utilities, Environmental Control Division will allow the . discharge of groundwater into the sanitary sewer if the maximum TVH level is 100 mg/i and the maximum total toxic organics 0 a BTEX} concentration is below 4 57 mg/l Application must be made to the City of Stockton prior to discharge of the waters The SlmptlRoekwplwwkplsn 3 910557 00