COMPLIANCE INFO - Laserfiche WebLink

Home Browse Search

MONITORING AND REPORTING i -iGRAM NO. R5-2004-XXXX -3- DEFENSE 3-DEFENSE DISTRIBUTION DEPOT SAN JOAQUIN SHARPE WASTEWATER TREATMENT FACILITY SAN JOAQUIN COUNTY GROUNDWATER MONITORING The Discharger shall sample existing wells MW-409A,MW-419A,MW-419B,MW-452A quarterly to assess potential impacts to groundwater quality beneath and adjacent to the primary disposal pond. In addition,monitoring well MW-470AR will be sampled annually to assess groundwater quality 500 feet down gradient from the primary disposal pond. Wells MW-410A, MW-416A, and MW-401A will be sampled quarterly the first year and annually thereafter to assess background groundwater quality. Additional groundwater monitoring requirements may be imposed if discharge to the temporary pond south of Building 404 exceeds 60 days in a calendar year or occurs more frequently than once every two years. Prior to sampling, the groundwater elevations shall be measured and the wells shall be purged in accordance with the current version of the DDJC-Sharpe/Tracy Comprehensive Field Work Plan (updated annually). Depth to groundwater shall be measured to the nearest 0.01 feet, Samples shall be collected using standard EPA methods. Groundwater monitoring shall include, at a minimum, the following: Type of Sampling Reporting Constituent 1 Units Sample Frequency Frequency Depth to Groundwater 0.01 feet Measurement Quarterly Quarterly Groundwater Elevation 2 0.01 feet Calculated Quarterly Quarterly Gradient feet/feet Calculated Quarterly Quarterly Gradient Direction degrees Calculated Quarterly Quarterly Total Dissolved Solids mg/L Grab Quarterly Quarterly Nitrate as Nitrogen mg/L Grab Quarterly Quarterly Total Kjeldahl Nitrogen mg/L Grab Quarterly Quarterly pH pH units Grab Quarterly Quarterly Trihalomethanes 3 µg/1 Grab Quarterly Quarterly Standard Minerals 4 mg/L Grab Annually Quarterly I All constituents will be collected during each scheduled monitoring event except Standard Minerals. Standard Minerals will be collected once per year from each monitoring well. 2 Groundwater elevation shall be determined based on depth-to-water measurements using a surveyed measuring point elevation on the well and a surveyed reference elevation. 3 Analysis shall be performed by EPA Method 8020 or equivalent 4 Standard Minerals shall include,at a minimum,the following elements/compounds: boron,calcium,chloride,iron, manganese,magnesium,potassium, sodium,sulfate,total alkalinity(including alkalinity series),and hardness. ISK 3/4/003