ARCHIVED REPORTS XR0001836 - Laserfiche WebLink

Home Browse Search

RPR-21-97 MON 08:06 Aid END/HMD FAX H0. 9163807011 P. 03 Lerner Texaco 521 North Cherokee Lane, Lodi Site Code 1324 19 Apn[ 1997 Page 3 well will be collected for laboratory analysis Vapor Wells Three 4-inch diameter vapor wells are Initially proposed (Plate 3) The wells will be roughly triangulated to allow an evaluation of potential spacial heterogeneities Each vapor well boring will be continuously logged to provide detailed Iithologic Information for remedial design and correlation to the CPT data It is anticipated that at least VE-1 and VE-2 will be screened from approximately 15 feet bgs to approximately 40 feet bgs. Because VE-3 is proposed in a location where the sod column is not thought to be significantly impacted,VE-3 may be screened nearthe groundwater's capillary fringe Final well design will be dependant on field evidence collected during drilling It is anticipated that four soil samples from each VE boring will be submitted for laboratory analysis Sod samples collected for analysis will need to be collected from the continuous core barrel and transferred into brass tubes. Analytical . Soil samples submitted for laboratory analysis will be analyzed for total purgeable hydrocarbons as gasoline (TPGg), benzene, toluene, ethylbenzene, and xylenes (BTEX), and methyl tertiary butyl ether (MtBE) MtBE will be included in the Method 8420 analysis Because of the age of the release and the transport characteristics of MtBE, I do not anticipate positive results for MtBE in soil Therefore, Method 8260 confirmation is only proposed for capillary fringe samples_ Groundwater samples will be analyzed for TPHg, BTEX, MtBE, and dissolved oxygen If MtBE is reported, Method 8260 will be used the subsequent quarter to verify each positive result If not reported in any of the welts, Method 8260 will be used to verify the results from two of the wells Dissolved oxygen and groundwater elevation data will be collected on-site Air samples will be submitted for analysis of volatile organic vapors by Method TO-14. Health Risk Assessment I will prepare a health risk assessment following the guidelines promulgated by the American Standards for Testing and Materials (ASTM) Method E-1739 I will use the Tier 1/Trer 2 Risk Based Corrective Action (RSCA) spreadsheet produced by GSI to evaluate the potential nsk increase that the gasoline release may have on both on-site commercial, and off-site commercial and residential, receptors The spreadsheet will be modified to reflect California's slope factor for benzene