Laserfiche WebLink
9 <br />• completion well 19-2 that is completed just above the A Groove in the Green <br />River Formation, six Uinta completions, and four alluvial completions. <br />1.2 Groundwater Sampling Equipment <br />A combination of three sampling devices have been used to collect the <br />groundwater quality samples provided in this document. Three of the original <br />five monitoring wells monitored throughout the Test Phase (20-9, 20-5, and 21- <br />2)were equipped with dedicated bladder pumps during the July 1999 sampling <br />trip. All other wells were initially sampled using a stainless steel bailer. Before <br />the second round of sampling in August 1999 all designated baseline ground <br />water monitoring wells were equipped with dedicated nitrogen gas displacement <br />pumps (Figure 1-5). All procedures outlined in the Groundwater, Surface Water <br />and Process Monitoring Pfan for the Yankee Gulch Sodium Minerals Project <br />• were followed and documented. <br />The use of dedicated nitrogen gas displacement pumps has proven, so far, to be <br />the best equipment for obtaining water quality samples from the deeper wells. <br />The only exception to this remains in the Dissolution Surface where precipitation <br />of the high total dissolved solids forms a blockage in the sample return line after <br />one to three sample collection cycles. <br />A minimum amount of pressure is used to displace the water in the pump and <br />bring it up the sample line to the well-head. Flow rates are low, all equipment is <br />dedicated and slow venting of the nitrogen accounts for little or no draw down in <br />the water column of the well during sampling. Purge volumes equivalent to the <br />sample pump and tubing are removed prior to sample collection, all field <br />parameters are recorded and the sample bottles are filled directly from the <br />• tubing in each well. A short piece of intermediate tubing is attached for all <br />filtered samples to accommodate the filter orifice and allow direction of the flow <br />through the disposable filter. Initially the tubing was decontaminated using <br />