ARCHIVED REPORTS XR0012562 - Laserfiche WebLink

Home Browse Search

-- i • ...•t.^° �'a '�a3 y.r .ti w� fir.! ,m„-4.+.i ;r � - 5' hC_ a t xa- } Texaco Envlronmental Services September 12, 1991 s 02320 1700 Page A 3.5 MONITORING WELL DEVELOPMENT Subsequent to installation,the monitoring wells will be developed manually using the surge and ball " techn -iue. Approximately threa to live well vo;umes of water will be extracted from each well by this method. Thls to;hnlque Is used to remove the fines left from drfiiing,to create an even sand pack and to rehabilitate tha borehoie sides. The fines are drawn through the well screen and subsequently bailed from the well. This process is repeated until the writer Is visibly clear of fines. Subsequent to development,the wells roll.be left undisturbed until water levels reach equilibrium. Prior to groundwater monitoring and sampling,the wellheads will also be surveyed. 3.6 GROUNDWATER MONITORING Prior to samping, the monitoring wells will be gauged using an ORS Environmental Equipment INTERFACE PROBE"to determine depth to water(DTW),and to check for the presence of separate-phase hydrocarbons(SP). The DTW Information will be used to construct a potentiometric surface elevation map and to determine the hydraulic gradient. k 3.7 GROUNDWATER SAMPLING l After groundwater monitoring,the mon�oring wells will be purged of a sufficient water volume to assure a representative sample. Samples will then be collected using a TefltnR sampler cleaned with an Industrial d3tergent and dWIlled mater. The%nate;samples will be poured from tha sampler into appropriate containers, acidified when necessary,labeled and placed on ice in an Insulated container for delivery to a State of Calgomla-certHied laboratory. The samples will be accompanied by a chain-of-custody manifest and will be analyzed for TPH-G a,-id BTEX by modified EPA methods 5030/8020/5015. 3.8 SOIL AND VIATER DISPOSAL Soil cuttings generated during the course of drilling will be stored on and co .=-4 with heavy plastic sheeting pending laboratory analyses. Soli disposal will be the responsibility of the chem/generator. Wastewater generated from steam cleaning of drilling augers and from monito'* -well development and purging will be collecieJ and stared on site in Department of TransportP,tlon(DOT)-approved 55-gallon drums,pending disposal at an EPA-permitted transport,storage and disposal facii,,,or discharged under the appropriate permits. Wastewater disposal will be the responsibility of the cliont/generator. GROUNDIVATER y�oawKa�R�r �_ ._ `._.;TCCHNoLoi.Y,INC.