ARCHIVED REPORTS_2014 - Laserfiche WebLink

Home Browse Search

Volatile organic compounds (VOC) were historically detected in well MW-2, including Dichlorodifluoromethane (CFC-12) from 1991 until last reported in 2007. 1, 2-Dichloropropane was detected in MW-2 from 1996 until last reported in 2006. Tetrachloroethene (PCE) has been detected in MW-2 since 1994, currently at trace concentration, and lastly Toluene has been sporadically detected, currently at trace concentration. Groundwater The groundwater well network consists of up-gradient well MW-1 and down-gradient wells MW-2, MW-3, and MW-4 (Figure 2). MW-5 and MW-6 were installed in 2010. Well MW-5 is hydraulically upgradient of the Secondary Site portion of facility and hydraulically side gradient of the Primary Site portion of the facility (Figures 2 and 3). Well MW-6 is hydraulically upgradient of all past landfilling operations at the site. All wells are equipped with dedicated purge and sampling pumps. All wells are surveyed based on the NAVD88 control rather than MSL. The purpose of wells MW-5 and MW-6 were to assess potential impact by the wastewater treatment ponds at the migrant labor housing facility, which are located immediately up-gradient of the Secondary Site. Groundwater samples are analyzed semiannually for the following field parameters: Elevation (Quarterly) Dissolved Oxygen pH Oxidation-Reduction Temperature Electrical Conductance Turbidity Groundwater samples are analyzed semiannually for the following monitoring parameters: Volatile Organic Compounds (VOC) Chemical Oxygen Demand Total Alkalinity Total Dissolved Solids (TDS) Total Hardness Bicarbonate Chloride Nitrate-Nitrogen Sulfate Calcium Magnesium Potassium Sodium Groundwater samples are analyzed every 5 years for the following additional constituents of concern (COC): Semi-volatile Organic Compounds Dissolved Metals Organophosporus Pesticides Chlorinated Herbicides Organochlorine Pesticides Polychlorinated Biphenols (PCB) 5-year CDCs were last taken during the first semiannual period of 2009. The next 5-year COC monitoring event will occur in the second semiannual period of 2014. Storm Water Storm water is collected from three (3) sampling points (SW-1 —SW-3) as identified in the WDR. Storm water flows are monitored semiannually for the same field and monitoring parameters as for groundwater specified above. There were no discharges during this monitoring period due to lack of rainfall. Harney Lane Sanitary Landfill 2 Department of Public Works/Solid Waste 1"Semiannual 2014 Groundwater Monitoring Report County of San Joaquin—July 31,2014