ARCHIVED REPORTS XR0011357 - Laserfiche WebLink

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All of the borings will be grouted with neat cement and finished off to grade The installation of the 2" diameter monitoring wells will be completed by a truck mounted hollow stem drilling ng The outside diameter of the hollow stem is 8 0 inches The soil sampling interval for this task and the laboratory analysis will be the same as in the hand borings stated above The overall depth of the proposed monitoring wells will be approximately 25 feet Ten feet of Schedule 40 P V C blank followed by fifteen feet of a Schedule 40 P V C screening interval will complete the monitoring well The screening interval will be of 01" slot size and will be placed so that 5 feet of screen will be above the water and 10 feet below the static water level The well screen packing material will be of Monterey Sand #2 for the entire screening interval and two feet above Then a bentonite/cement seal will be tremied up the annulus of the boring to the surface A waterproof chesty box will be installed to protect and seal the access to the well along with a locking watertight well cap Development of the wells will be completed within 48 hours of the installation of the well to remove the fines and sediments during installation and establish a efficient conduit for monitoring the aquifer Upon completion of the development tasks the well will be sounded for depth to water and a three to five well volume purge will be completed The purging activities will be completed with a Grundfos submersible or ISCO peristaltic pump and the pH, Temperature, Conductivity and turbidity will be monitored to establish that the well is producing representative water during it's recharge for a accurate sampling event Next, the well will be sampled with a clean stainless steel bailer and two V O A 's will be collected for laboratory analysis (TPH-Gas / BTXE ) All development and purge water will be contained on site in D O T 17 drums for containment and determination of proper disposal Surveying of the new monitoring wells will be completed to the top notched edge of the well casing, relative to a arbritary datum point It will be the goal of this soil boring and monitoring well routine to fully define the extent of the soil & water contamination It is also our intent to determine the geology of the area where the borings are placed to further define the most appropriate means of remediating the contamination from these zones 5