ARCHIVED REPORTS_XR0003711 - Laserfiche WebLink

Home Browse Search

r r 1 Mr Chuck Carmel . February 14, 1994 Page 3 accomplished with two granular activated carbon (GAC) vessels, each having 1,000-pound capacity Groundwater is extracted from the well via a submersible pump Discharge of the treated groundwater is to the city industrial sewer system under Wastewater Discharge Permit No 151 issued by the City of Lodi: Public Works Department Installation and start-up of the GWETS occurred in October 1992 The GWETS was shut down on April 19, 1993, due to nondetectable concentrations of hydrocarbons in the water The SVETS consists of eight soil vapor extraction wells (VE-1, VE-2, VE-3, VE-4, VE-5, VE-6, VE-7 and VE-8) and a soil vapor treatment system The soil vapor treatment system is composed of a vacuum compressor pump followed by a King-Buck-Hasstech catalytic oxidizer that has a design treatment flow rate of 100 cubic feet per minute (cfm) of soil vapor The system is operated under Permit to Operate No N-1081-1-0 issued by San Joaquin Valley Unified Air Pollution Control District Operating Conditions This Quarter. The groundwater extraction and treatment system did not operate during the third quarter of 1993 The SVETS operated continuously at 100 ctm during this quarter Vapors were extracted from wells VE-3, VE-4, VE-6, VE-7 and VE-8 Results and Discussion The current, historical, and total concentrations of BTEX and TPH in the extracted soil vapor are shown in Table 4 The laboratory reports for the sampling events of the SVETS are presented in Exhibit B Influent concentrations appear to be steadily declining, indicating that the hydrocarbons are being successfully remediated Figure 2 shows the area thought to be influenced by operating VE-3, VE-4, VE-6, VE-7, and VE-8 at an average flow rate of 20 cfm (20 cfm is based on the assumption that the total flow rate of 100 cfm is distributed equally between these wells) This operational radius of influence (OROI) shown on Figure 2 is ten feet This is based on extrapolation of radius of influence measurements collected during the original vapor extraction test in 1990 Radius of influence was not measured during the March 1993 sampling of vapors The OROI is based on conservative assumptions related to soil venting These conservative assumptions are (1) the soil venting from individual wells do not influence neighbonng wells, or to be more specific, the influence on individual wells from soil vapor extraction is not cumulative, (2) radius of influence is based on vacuum pressures that are at, or above, 0 1-inch water cglumn, and (3) biological degradation of gasoline hydrocarbons is not • Use or disclosure of data contained on this sheer is subject to the restriction specified at the beginning of this document 7481 RLPORTSIAUG93 QTR RPT I