Laserfiche WebLink
MITTELHAUSER CORPORATION <br /> GROUNDWATER MONITORING AND SAMPLE COLLECTION <br /> FIELD PROTOCOL <br /> Water Level Measurement <br /> Monitoring well reference elevations are measured to a marked or notched <br /> location at the top of the well pipe which has been surveyed by a licensed <br /> surveyor Depth to water is measured using an electric water level indicator and <br /> referenced to the surveyed mark at the top of the well pipe. Alternatively, a steel <br /> or aluminum yardstick covered with water-finding paste is attached to a steel tape <br /> and lowered until part of the yardstick encounters the water in the well The <br /> measured length of the steel tape is added to the unaffected length of the <br /> yardstick as measured from the top of the yardstick to a point where the <br /> discoloration of the water-finding paste begins Depth to water-level <br /> measurements are made to the nearest 0 01 foot. <br /> Water levels are measured prior to well development and well purging for the <br /> purpose of sampling <br /> Free Product Layer Thickness Measurement <br /> Free product measurements are made to the same reference point as described <br /> above for water-level measurements Free-product layer thickness <br /> measurements are performed in one of several ways. <br /> Measurement to the top of the free-product layer may be performed using an <br /> electric petroleum hydrocarbon indicator An electric water-level indicator is <br /> covered with product-,finding paste and is lowered into the well until the water- <br /> level sensor indicates that water has been encountered The probe is then <br /> withdrawn from the well and the affected length of the product-finding paste is <br /> measured Alternatively, a steel or aluminum yardstick covered with product- <br /> finding paste is attached to a steel tape and lowered until part of the yardstick <br /> encounters the free-product layer The measured length of the steel tape is <br /> added to the unaffected length of the yardstick as measured from the top of the <br /> yardstick to the point where discoloration of the product-finding paste begins <br /> The total product layer thickness is determined by finding the difference between <br /> the measured depth to product and the measured depth to water <br /> In most instances it is possible to place both water-finding paste and product- <br /> finding paste side by side on the same yardstick and directly measure the <br /> thickness of the discolored product-finding paste from the yardstick Depth to free <br /> product or free-product thickness measurements are made to the nearest 0 01 <br /> foot <br /> I <br /> i <br />