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CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL VALLEY REGION MONITORING AND REPORTING PROGRAM NO. R5-2006-XXXX CALIFORNIA WATER CODE SECTION 13267 FOR CHEVRON PIPELINE COMPANY SAN JOAQUIN COUNTY Chevron Pipeline Company (Discharger) owns and operates a refined petroleum products pipeline near the intersection of Corral Hollow and Grant Line Road in Tracy. Groundwater, at a depth of 10 feet, is polluted with total petroleum hydrocarbons as diesel and gasoline (TPHd and TPHG), benzene, toluene, ethylbenzene and xylene (BTEX) and polynuclear aromatic hydrocarbons (PNAs). This pollution impaired the beneficial uses of this water resource. In 1987 the Discharger excavated about 100 cubic yards of soil containing petroleum hydrocarbons, and in 1997 operated a dual-phase groundwater and soil vapor extraction system. Since 1997 the Discharger has monitored the site to confirm that the remaining hydrocarbons are naturally degrading. This Monitoring and Reporting Program (MRP) is issued pursuant to Section 13267 of the California Water Code and is necessary to delineate groundwater pollutant plumes and determine whether remediation efforts are effective. Existing data and information about the site show the presence of various chemicals, including TPHd, TPHg, benzene and naphthalene emanating from the property resulting from the Discharger's current or past operation. The Discharger shall not implement any changes to this MRP unless and until a revised MRP is issued by the Executive Officer. This MRP replaces the requirements listed in MRP No. 96-814, which was issued on 24 September 1996. Prior to construction of any new groundwater monitoring or extraction wells, and prior to destruction of any groundwater monitoring or extraction wells, the Discharger shall submit plans and specifications to the Regional Board for review and approval. Once installed, all new wells shall be added to the monitoring program and shall be sampled and analyzed according to the schedule below. GROUNDWATER MONITORING As shown on Figure 1, there are five monitoring wells remaining at the site, designated MW-5, MW-6, MW-7, MW-8 and MW-12. The groundwater monitoring program for MW-6, MW-8, MW-12 and any wells installed subsequent to the issuance of this MRP, shall follow the schedule below. If sampling requirements for elimination of constituents have been met under the previous MRP, the Discharger is not required to sample for those constituents again based on the new requirements. Monitoring wells with free phase petroleum product or visible sheen shall be monitored, at a minimum, for product thickness and depth to water. Sample collection and analysis shall follow standard EPA protocol.