Laserfiche WebLink
M moldenhauer <br /> ,�; ` 3j .ALEX MOLDENHAUER,L.S.,REe engineering PRINCIPAL <br /> C company Isis <br /> ,t1 V IM1M1hiL.'�l.f��T•' <br /> 337.871 <br /> June 26, 1989 <br /> Mr. John Tomko <br /> Regional Water Quality Control Board <br /> Central Valley Region <br /> 3443 Routier Road <br /> Sacramento, CA 95827-3098 <br /> Dear Mr. Tomko: <br /> On Friday June 16 Southwest Hide Company contracted with Puriance <br /> Drillers of Modesto to probe the total depth and clean out two abandoned <br /> production wells on their Manteca property. It was orginally thought <br /> that this procedure could be completed using the cable tool drilling <br /> method. <br /> Proir to using this method, however, a water jet was placed in the <br /> wells in an attempt to displace sediments and determine the total depth <br /> of the wells. From this investigation it was determined that well <br /> 123 was originally constructed to a depth of 135 feet and well 122 <br /> was originally constructed to a depth of 91 feet. ( See Exhibit A) <br /> It should be noted that both of these wells were filled with sediment <br /> to approximate depths of 50 feet below ground surface elevation. <br /> The fact that each of these wells contain large amounts of sediment <br /> seems to indicate that the casings are no longer intact. While bringing <br /> the water jet up well 122 this fact was confirmed when the pipe became <br /> stuck on what was believed to be a torn edge of the casing. Also, <br /> a gravel layer was encounter between 56 and 60 feet which probably <br /> indicates a seperated casing where the gravel could freely enter the <br /> well . Bacause of this , the drilling contractor felt that it would <br /> be very risky to clean out the wells with either the cable tool , a <br /> high pressure water jet system or redrilling inside the existing casing. <br /> lie stated that these kind of pressures would probably colapse the casings <br /> leaving us with a very difficult abandonment when the time came. A <br /> colapsed casing would also make it impossible to run a television camera <br /> down the well to determine the depth of perforations. <br /> 1107 KENNEDY PLACE,SUITE 7,DAVIS.CA 95616•(916)756-22 50 <br /> .i n of 1 1 n f fu 1 n n n1 c .f . T . ^f T c P R !1 I F r T P I A N M F R S <br />