2007-10-30_REVISION - M1977208 - Laserfiche WebLink

Home Browse Search

Oct 30 2007 7:SOf1M Cemex Inc. 303 823 2199 p.5 Ms. Erica Crosby October 29, 2007 Page 4 • Set up a pumping syrtem in the southwert pond to move water firm this pond into mater truckr ured for road watering or other conrumptive are, thereby rrdueang the impact of thin pond on C-Pit. • Once the ?008 irrigation rearon rnmmencer in /Ipril--May 2008, monitor the C-Pe't highwall far reepage, mamtor the r'sned patron of the Canal and monitor worry leveLr in tl~e routhwertpond • GFt12EX wit! continue to explore wayr to rue the C Pii water in the proars that do not nears other adverre effects. • Propose alternatives to water spraying ar a dust rupprerrant in the C-Pit aria for approval under the CPDHE Title VAirPernrit. If their it no tign~cant reduction in obrerved inflow to C-Pit via 1Jre western highwall a'unng next rummer'r irrigation rearon, CEMEX will conduct further mvertigationr to determine the rourre(rJ of the inflow. There invertigatianr may include additional flaw gauging in the Cana! at dacatianr further to the north thare stye gauging ronducled by Brown and Caldwell during rummer 200?, and/or inrtallation of additional piezameterr. If it it determined that seepage is rian~cant along one or more partionr of the rspproavnately 1,900Joat reach went of C-Pit that it cut into bedrock, CEMEX will eroordlnate with Northern to determtne the available optionr to lint the canal to reduce reepage in this ann. 3. The report indicates that leakage from the A-Pit water line is a possibility due to the past occurrence of the line breaking and the fact that the highwall in the vicinity of the A-Pit [sic] is wet Please provide a plan to investigate the condition of the A-Pit water line and a mitigation plan in the event water is migrating into the C-Pit CEMEX Response: AltF.augh it it trite that limited array of ice formation have been obrerved in the part in the rhaded portions of the northeast GPit highwall during the winter montlzr, CEMEX proporer to defer tertritg the fl-Pit /tree at this lime, pending the tuults of the prngrv~o out/saed afiove. Converrationr with the contractor who ins7aded and maintain: the A-Pit /tine indicate that bared an hir experience, tin'r type of line rarely hay rmall kaki, but rattier ready to perform err intended or fail duo to h'ne breakage, at which dime repairr air made. The line u a 6-inch HDPE line with tbermaUy welded jaintr. Water from tbir rystem rontinuer to be rucressfu!!y delrbered to the cement plant spray tower without any indication of Torres. Part experience with thir line has rhvwn that arty rigrriftcant leaks quickly exprerr themselver err wet, panted arem~ an the rurface, due to the rhallow roily overlaying the bedrock along the pipek'ne mute. In the event that the what we currently befieve to be the major rotn~ce of inflow to C-Pit (reepage from the Feedn Canal and dart ruppresrran mater) rr eliminated, and C-Art water lens/. rontdmre <o rise, CEMEX will conduct hyd%rtatic tertin& to confirm whether err not any leakage is detectable. This wiJ,~ entail presrurizing the line while cla~ing the valve at the dirclrmge end of the yrtem near the spray tower. If the line does not hold prerrure, the ryrtem will be rout down, the /ins read be a"rainzd afall water and cleanzd out by wring compmrred air, and the syrtem will then be filled with pre;rurized heliumgar. Helium gas deteclarr will be used to nmdk the alignmext of the pipeline and determine tAe hcatian of t1>e leak err leaks, and She leaks will be repaired ifthey are located in an area that may be af~ctin8 C-Pit. 4. CE1~ffiX is required to monitoring [sic] wildlife on the site in the vicitity of C-Pit. Please inform the Division if the wildlife monitoring and reporting plan will change as a result of the backfilling of a majority of the pit and the recently installed net on the exposed wafer in the C-Pit. CEMEX Response CEMEX nail zvntinue to monitor wildlife in the C-Pit vicinity. Thlr it part of daily operations monitoring pmgram. No evidence of wildlife outride ofpigeons bar been abrerved in the C- Draft Response to t0-5-07 Adequacy Review TR-9_REV2