Laserfiche WebLink
m <br /> q� <br /> y 4^1.r' -• � +7. . r}}. ;''�T+V ..t „�• :•tI-• •. SCf �hk _! f'q.°_ <br /> h- <br /> V" <br /> GROUNDWATER T'ECUNOL GY <br /> STANDARD OPERATING PROCEDURE <br /> CONCERNI-MG MONITORING WELL INSTALLATION <br /> SOP 13 <br /> The boreholes for the monitoring wells shall be drilled <br /> using a truck mounted hollow sty+ augur drill rig. The <br /> -- outside diameter (O.D,.) of the anger should be sa minimum <br /> of eight inches when installing 4-inch veli screen. The <br /> hollow stem auger provides minimal inter-option of drill- <br /> ing while permitting soil sampling at aepecific intervals. <br /> Soil samples can be taken at desired depths by hammering <br /> a conventional split barrel sampler containing precleaned <br /> a inch brass sample tubes. <br /> ' toring wells to be <br /> The construction details of the moni <br /> drilled at the site are graphically depicted in.the <br /> attached figure titled "Typical Detail of Monitoring Well <br /> Construction" (See Figure 1) . The wells should be cons- <br /> tructed of 4 inch PVC, .020 inch machine slotted screen <br /> and blank casing. The screened portion of the well will <br /> extend i feet above and 10 feet below the present water <br /> table. An appropriate sand pack as determined by grain <br /> size analysis shall be placed in the annular space between <br /> the casing and drilled hole to inhibit silt buildup around <br /> the well. An annular seal installed above the sand pack <br /> should consist of bentonite pellets overlain by neat <br /> cement or cement grout to the surface. The wellhead shall <br /> be protected below grade within a traffic rated street box. <br /> Each well shall have a permanently attached identification <br /> plate containing the following information (1) well Number, <br /> (2) Wellhead Elevation, (3) Depth of well, (4) Screened <br /> Interval. <br /> Subsequent to installation the wells shall be developed <br /> to remove silts and improve well performance. The well <br /> development shall be conducted by air lifting the water <br /> within the well until groundwater pumped from the wells <br /> is silt free. <br /> To assure that cross contamination does not occur between <br /> the drilling and development of successive wells all <br /> equipment contacting subsurface soils or ground water <br /> shall be steam cleaned. The steam cleaned equipment <br /> should include but net limited to the following (1) Dril- <br /> ling Augers, (2) Split Barrel Sampler, w(3) Groundwater <br /> Monitoring and Sampling Equipment, ( ) P e <br /> nt <br /> Piping and Sparging Equipment. <br /> + � GR[1l NMATER <br /> L'�J TMHN'0U)C'.Isc. <br />