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Proiect Number 2098RV45 November 30 2017 to review and approve for acceptance. After approval for acceptance, the IDW will be disposed within 4 weeks. If the profiling show that the soil is contaminated, they will be disposed in Recology's Portrero Hill facility in Fairfield, CA. If the IDW is not contaminated, it will be disposed in Western Placer County Waste Management Authority's facility in Lincoln, CA. Decontamination water will be disposed at East Bay MUD in Oakland, California for recycling, if it is non-hazardous. Otherwise, it will be disposed at California Asbury Environmental Services. 2.3 Groundwater Sampling and Analysis A minimum of 3 days after well developing, EzC will mobilize to the Site and perform groundwater monitoring. 2.3.1 Groundwater Monitoring and Sampling Depths to groundwater will be measured at all newly installed groundwater monitoring wells with a Solinst water level meter to the nearest 0.01-foot indexed from a mark placed at the top of the well casing (generally the north side). Depths to water will be used to calculate the groundwater elevation at each well and a groundwater gradient plot for each zone can then be generated. Low-Flow Sampling Method During the groundwater sampling event, groundwater samples will be collected utilizing the low-flow sampling method. In this method, groundwater is extracted from the well at a very low rate, approximately 500 milliliters per minute (mL/min), and drawdown of the water table is stabilized. Water is recovered from the more hydrogeologically conductive areas of the water bearing zone around the well screen, and monitored with water quality sensors for stability to determine chemical change from well water to formation water. Once stabilization occurs, a sample can be taken with the assurance of representative formation water and the least amount of geochemical disruption to the sample. This sampling system has several advantages: ■ Improves sample quality; ■ Reduces wastewater created by large volumes of sample purging; and ■ Saves time in the field with preliminary set-up of sampling events. During the low-flow purging, groundwater parameters will be monitored in the field with a QED Model MD-20 Flow Cell. The MD-20 Flow Cell measures temperature in degrees Centigrade (OC), dissolved oxygen (DO) in milligrams per liter (mg/L), electrical conductivity in milliseconds per centimeter (mS/cm), pH (in pH units), and ORP (oxygen reduction potential) in millivolts (mV). After purging, the low-flow method will also be used to fill sample containers. Each sample will be decanted into three laboratory-provided 40-milliliter VOA vials preserved with dilute hydrochloric acid. Care will be taken to verify that headspace or bubbles do not exist in the VOAs and each container will be sealed using a Teflon®- lined lid. The samples will be labeled and placed in an iced cooler maintained at 4° Centigrade, accompanied with a chain-of-custody document for transport to the analytical laboratory. All downhole equipment will be cleaned prior to use by either steam cleaning or washing using a Liquinox solution and double-rinsing with clean potable water. E2C Remediation 7