Laserfiche WebLink
KLEINFELDER <br />A-5 Vadose Zone Monitoring <br />1. Prior to conducting lysimeter sampling, the pressure -vacuum equipment is checked and <br />cleaned. A Soil -Moisture hand pump with a pressure -vacuum gage is used to measure <br />residual and implied pressure -vacuum. Nitrogen gas is used to purge the lysimeter <br />system for sampling. An air pump is available as a back up. <br />2. Approximately one week to one month prior to conducting the sampling, the residual <br />pressures at the air -line of each lysimeter are measured ad the vacuums reset to <br />manufactured recommended value (usually 50 centibars). The measurements and applied <br />vacuums are noted on a sampling log form. Kleinfelder has found that resetting the <br />lysimeters vacuums before the sampling yields good sample recovery. <br />3. The residual pressures are measured just prior to collecting the sample. The water line is <br />then opened and nitrogen gas applied to the air line until either fluid or air is discharged <br />(for dry lysimeters). The sample is contained in a 1 liter unpreserved bottle and the <br />volume recovered is estimated. The fluid is then poured into appropriate preserved or <br />unpreserved bottles of the requested analysis. <br />4. After the sample is collected, the lysimeter vacuum is reset to the manufacturer's <br />recommended value. The lysimeter is also tested to evaluate potential leaks that may <br />cause vacuum pressure loss. <br />A-6 Leachate Monitoring <br />1. The leachate riser or wells are first opened and allowed to equilibrate with the <br />atmosphere. <br />2. The leachate elevation is then measured from a set location using a conductivity -based <br />water -level meter. The level is generally measured from a surveyed mark on the north <br />rim of the casing. <br />3. A leachate sample is then collected using a clean, disposable bailer. <br />4. The sample is labeled and immediately stored in an iced cooler pending transport to the <br />analytical laboratory. The sample is logged on a chain -of -custody. <br />20-1108-33.001/201181188 Page A-7 <br />2001, Kleinfelder, Inc. October 17, 2001 <br />