Laserfiche WebLink
-'- GROUND-WATER MONITORING AND SAMPLING PROCEDURES <br /> Prior to sampling,the depth to water was measured in all monitoring wells using an electronic immersion probe. <br /> All measurements were read to the nearest 0.01 foot. If free product was present,the depth to free product and <br /> the depth to water was measured using art interface probe and an observation sample was collected with a clear <br /> teflon bailer for confirmation. No analytical samples were collected from monitoring wells containing more <br /> than 0.25 inch of free product. <br /> ' -I;te monitoring wells were sampled on September 14, 1989. Prior to purging,each well was checked with a clear <br /> teflon bailer in order to observe the possible presence of floating hydrocarbons. Purging was accomplished using <br /> a stainless steel or teflon bailer. The bailer was thoroughly cleaned prior to each sampling using a trisodium <br /> phosphate solution followed by a 10% methylalcohol solution, and then rinsed twice with potable water. The <br /> wells were purged prior to sampling until pH,conductivity, and temperature values stabilized. Generally, this <br /> resulted in the removal of approximately 3 to 5 well volumes of ground water from each well during the purging <br /> process. The water obtained from purging was placed in Iabeled 55-gallon drums and stored on-site. The bailer <br /> line was replaced after each sampling. Samples recovered from each well were decanted in o two appropriately <br /> prepared and labeled 40-m1 volatile organic analysis(VOA) bottles. A travel blank(numbered as MW-26)and <br /> - a duplicate sample from MW-24 were also submitted for quality assurance. The sample bottles were,immediately <br /> placed in an ice chest and maintained at 4•C.until delivery to a StMe of California licensed laboratory. Routine <br /> chain-of-custody procedures were employed. S <br /> Y i # <br /> -. 6' <br /> iMi <br /> A--1 <br />