FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

CLEARWATER G R b U P, I N C. ur activities to insure that the am purging sample is representative of the aquifer. Purging will continue until at least three well casing volumes have been removed, the physical parameters stabilize, or until the wellcompletely �. dewaters. Stability is defined as a change of less than 0.2 pH units, less than 10% in micro mhos, and less than 1.0 _d gree Centigrade. Wells which dewater or demonstrate a slow recharge, ay be sampled after fewer than _ three well volumes have been removed. ell purging information will be recorded on a purge data sheet. .All metes will be calibrated daily. Purge water will be stored on site in D.O.T. "approved 55 gallon drums, sealed and labeled. The water will be removed-to an appropriate disposal facility-by a licensed hauler. Ground water sam les-will be collected ' p co ediately after purging or when the well has recharged'to at least 70% of its static water level. Samples will be collected using polyethylene bailers, either disposabie or dedicated to the well. Samples for analytes most sensitive to volatilization will be collected first. Water samples will be placed in the appr priate container for that analysis, labeled, documented on a chain of custodyorm and placed on ice in 'a cooler for transport to a state-approved analytical laboratory. To prevent contamination of the samples, CGI persornel will adhere to the following procedures in the field: • A new, clean pair of latex gloves will be ed for each well to be sampled. • Groundwater samples will be collected in the expected order of increasing degree of contamination.. �f I bbb When collecting samples for volatile or anis analysis, CGI personnel will minimize the amount of air passing through the sample. ' 'This helpsFi i prevent the air from stripping the volatiles from the water. Sample bottles should be filled by slowly running the sample down the side of the . bottle until there is a convex meniscus over the mouth of the bottle. The lid is then carefully screwed onto the bottle. such that no air bubbles are present within the bottle. If a bubble is present, the cap is removed and additional water is added to the sample container. After resealing the sample container, if bubbles still are present inside, the sample container is discarded and the procedure is repeated. CLEARWA=GROUP,INC. 4 June 2,1995 r �E