Laserfiche WebLink
Groundwater Monitoring Protocol <br /> Monitoring depth to water and free product thickness within wells <br /> ' at the site will be conducted using an Interface Probe and <br /> Surface Sampler. The Interface Probe is a hand held, battery <br /> operated device for measuring depth to petroleum product and <br /> depth to water as measured from an established datum (i.e. , top <br /> of the well casing which has been surveyed) . For consistency, <br /> all measurements will be taken from the north side of the <br /> wellhead at the survey mark. To assess potential infiltration of <br /> ' fine grained sediments, total well depth will also be sounded. <br /> Product thickness is calculated by subtracting the depth to <br /> ' product from the depth to water. In addition, water elevations <br /> are adjusted for the presence of fuel with the following <br /> calculation: <br /> ' (Product Thickness) ( .8)+(Water Elevation) <br /> = Corrected Water Elevation <br /> Note: The factor of 0. 8 accounts for the density difference <br /> IPbetween water and petroleum hydrocarbons. <br /> Newly installed wells will be allowed to stabilize for 24 <br /> ' hours after development prior to free product inspection. <br /> An acrylic Surface Sampler will be used for visual inspection of <br /> ' the groundwater in order to note sheens (difficult to detect with <br /> the Interface Probe) , odors, microbial action and sediments. The <br /> sampler is calibrated in inches and centimeters for visual <br /> inspection of product thickness. <br /> To reduce the potential for cross contamination between wells, <br /> the monitorings will take place in order from the least to most <br /> ' contaminated. Wells containing free product will be monitored _ <br /> last. Between each monitoring the equipment will be <br /> decontaminated. <br /> ' Water level data collected from the wells will be used to develop <br /> a groundwater equipotential contour map for the project site. <br /> ' Groundwater flow will be estimated to be perpendicular to <br /> equipotential lines drawn on the map. <br /> a <br />