Laserfiche WebLink
Paul Banks <br />May 13, 2004 <br />Page 4 <br />would affect the drawdown in the wells and thus their ability to produce. As we do not have any <br />data available regarding the historic pumping rates of these wells, we examined the State Master <br />List database for pumping information on other wells in the area. Based on this data, we ran <br />simulations with a 640 gpm pumping rate, under scenarios of a single day of pumping and then <br />under cyclic one day on-one day off pumping. Note that each "day" was a full 24-hours; this is <br />considered very conservative, as it is unlikely that any well use for irrigation via center pivot <br />sprinklers would take place continuously for 24 hours at a time. To simulate the superimposed <br />drawdown resulting from the mine operations, the transmissivity factor in the analysis was <br />lowered through successive runs and the resultant predicted well drawdowns compared. <br />The results of this analysis indicate that single day pumping, starting with a <br />transmissivity of 100,000 gpd/ft, could be maintained up through reductions due to mine <br />drawdowns of 8-feet, or about 1/3 of the available saturated thickness. For starting <br />transmissivities in the 60,000 gpd/ft range, pumping could be maintained under mine induced <br />drawdowns of up to 5 feet. For the cyclic pumping scenarios, a similar set of results was <br />obtained, although it is likely that a limit to the number of cycles that could be achieved would <br />be reached at some point in time. We conclude from this analysis that the Evans wells could <br />continue to produce at the rates simulated but that there would be either increased drawdowns <br />during pumping, or somewhat decreased well yields, or both, for the closer in wells, depending <br />on exactly how they are operated. The wells located somewhat further north of the property <br />should be able to continue to pump effectively, especially if the pumping cycles are of shorter <br />duration than those simulated. <br />Please let us know if you have any questions concerning the contents of this letter report <br />or our analyses carried out for this study. We appreciate the opportunity to have been of service <br />to you on this project. <br />Sincerely, SE°; ~ :°irss~ H' <br />,~~~. `~i~r~il'xil~Bf'9i~~o~ <br />t ~ <br />FhillippY/L. IVT-artin, C.P.G. \bd/ ,z <br />Vice President .~ `~Ay<< 1. MP~EO <br />PLM:mta <br />Martina and Wood LC~aler Consultants, lac. <br />