WORK PLANS - Laserfiche WebLink

Home Browse Search

PES Environmental, Inc. Ms. Emily Cushman November 4, 2016 Page 4 Monitoring Well Sampling PES will subcontract with Blaine Tech Services, Inc. (Blaine Tech) of Sacramento, California to collect depth to water measurement, and conduct groundwater monitoring well purging and sampling. Depth to groundwater measurements will be collected by Blaine Tech from the wells prior to commencing groundwater purging and sampling activities. Depth to groundwater measurements will be recorded to the nearest 0.01-foot using an electronic sounding probe. To minimize the potential for cross-contamination of wells during the collection of groundwater-level measurements, the portion of the sounding probe that contacts the well casing or groundwater will be cleaned with a Liqui-Nox®-solution and double-rinsed with deionized water between measurements. Depth-to-groundwater measurements will be converted to groundwater-level elevations referenced to mean sea level. Prior to the collection of groundwater samples from the new monitoring wells, water in each well casing will be purged using a low-flow bladder or electrical submersible pump. To reduce the potential for cross-contamination of wells during well purging, a new pump bladder, grab plate, and pump tubing will be used, and the submersible pump housing will be triple-rinsed with a Liqui-Nox®-solution prior to purging each well. Each well will be purged at rates no greater than 1,000 milliliters per minute until water quality parameters stabilize. Purge water quality parameters including temperature, pH, specific conductance, turbidity, dissolved oxygen (DO), and oxygen-reduction potential (ORP) will be monitored periodically and recorded. Following well purging, groundwater samples will be collected from each well. The groundwater samples collected from each well will be placed in laboratory provided sample containers. Field quality assurance/quality control (QA/QC) samples for groundwater monitoring events will consist of equipment blanks (one per day), travel blanks (one per shipment), and field duplicate samples (a minimum of one per day or one per ten samples or fraction thereof). The sample bottles will be labeled, packaged, and stored in a chilled, thermally insulated cooler until delivery to the laboratory. Each sample will be assigned a sample number and logged on the Chain-of Custody Record. A Chain-of-Custody Record will accompany each sample shipment to the laboratory to document sample possession from the time of collection. All groundwater and field QA/QC samples will be submitted to the laboratory for analysis of total petroleum hydrocarbons as gasoline (TPHg) and VOCs using USEPA Test Method 8260B. 148400101ww5.doex