Laserfiche WebLink
TREADWELL & ROLLO <br /> After the well casing was placed into the annular space within the augers, a filter sand <br />' pack (Monterey Sand No. 3) was tremied into the place between the casing and the soil. <br /> The augers were intermittently raised to facilitate placement of the sand pack. The sand <br />' was placed from the bottom of the borehole to approximately two feet above the slotted <br /> section A two-foot- thick bentonite pellet seal was then placed above the sand pack and <br /> allowed to "swell" prior to placement of the cement-bentonite grout In the remaining <br /> annular space. The well was completed with an Emco-Wheaton traffic-rated utility box. <br /> tMs. Margaret Lagorio of the San Joaquin County Environmental Health Division <br /> monitored the well completion. <br /> 1 <br /> 4.3 Well Development <br />' The monitoring well was developed on 4 October 1993 using a surge block and a <br /> stainless steel bailer. The surge block and bailer were thoroughly cleaned with a <br />' laboratory detergent solution (trisodium phosphate and deionized water) and thoroughly <br /> rinsed with deionized water prior to use Physical water quality parameters, including <br /> temperature, acidity, and electrical conductivity, were measuredo <br /> eridicall during <br /> p Y g <br /> development. Observations of color, turbidity, and sediment content were also <br /> 1 documented. The well was developed until the physical wateruali <br /> Q tY parameters <br /> s <br />' stabilized and at least 10 well volumes of groundwater had been evacuated Mr. Michael <br /> Collins of the San Joaquin County Environmental Health Division monitored the well <br />' development activities. <br />' Following well development, groundwater samples were collected from the monitoring <br /> well for chemical testing The groundwater samples were decanted from an individually- <br /> wrapped, factory cleaned, disposable plastic bailer into sample containers prepared and <br /> provided by a state-certified contracted analytical laboratory (American Environmental <br />' Network, in Pleasant Hill, California) in accordance with standard laboratory procedures <br /> 5 <br /> 11070707 PJC 18 November 1993 <br />