Laserfiche WebLink
{ <br /> 4 r rpt <br /> k <br /> GROUNDWATER TEC11NOLOGY <br /> STANDARD OPERATING PROCEDURE <br /> CONCERNING GROUNDWATER MONITORING <br /> SOP 8 <br /> Groundwater monitoring of wells at the site shall be <br /> conducted using an ORS Interface Probe and Surface <br /> Sampler. The Interface Probe is a hand held, battery <br /> operated device for measuring depth to petroleum product <br /> and depth to water as measured from an established datum <br /> (ice. , top of the well casing which has been surveyed) . <br /> Product thickness is then calculated by subtracting the <br /> depth to product from the depth to water. In addition, <br /> water elevations are adjusted for the presence of fuel <br /> with the following calculation: <br /> (Product Thickness) (.B)+(irater Elevat:.on) <br /> - Corrected Water Elevation <br /> ?tote: The factor of 0.6 accounts for the density <br /> difference between water and petroleum <br /> hydrocarbons. <br /> The Interface Probe consists of a dual sensing probe <br /> utilizing an,optical liquid sensor Und electrical con- <br /> ductivity to distinguish between water and petroleum <br /> products. A coated steel measuring tape transmits the <br /> sensor's signals to the reel assembly, where an audible <br /> alarm sounds a continuous tone when the sensor is <br /> immersed in petroleum product and an oscillating tone <br /> when immersed in water. The Interface Probe is accurate <br /> to I/16-inch. <br /> A Surface Samp er shall be used for visual inspection of <br /> the groundwater to note sheens (difficult to detect with <br /> the Interface Probe) , odors, microbial action, etc. <br /> The Surface Sampler used consists of a 12-inch long cast <br /> acrylic tube with a Delrin ball which closes onto a <br /> conical surface creating a seal as the sampler is pulled <br /> up. The sampler is calibrated in inches and centimeters <br /> for visual inspection of product thickness. <br /> To reduce the potential for cross contamination between <br /> wells the monitorings shall take place in order from the <br /> least to most contaminated wells. Wells containing free <br /> product should be monitored last. Between each; monitoring <br /> the equipment shall be washed with laboratory grade <br /> detergent and double rinsed with distilled water. <br /> CROI'KAkATER <br /> ��+ TECHRpI.( Y.INC. <br />