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SFNT BY ~ X17-97 15 ~ 31 ; I NDFPFNDh7VCE M I N l~ ~ 303 832 8106 ~ # 6 selection, discussed later, appeared to best represent the field measurements, If them are other imperfections at higher elevazioae, they may be described by the more "standud' 2t 1 mm diameter. An czautple of the result of many of the interim cottgnttations using the revisrd "initial' location and size, specifically the project:d head-flow relationships for the St2.5 mm + 2f1 mm defect coafigurtttion acrd the St2.5 tom single imperfeaioa ennftguration, ue provided as AuarR*~.:.r!c 6 and 7. One of the variants of the configuration assumed a 6t3 mm diartteter imperfection az the third interval (rt 9257.5 ft., between elevations 9255 [t. and 9260 tt.), and ao additional hrgterfectioae at higher elevations. This wnliguration, the graph for which is provided as Attachmrnt 8, seems to represent a good fit to the field data. It mould, CC&V believra. be used to check the LVSCS pump system for future capability. However, it would be prc[narure to dtxtend entirely on this onnfiguration until higher pregnant solution heads have been measured. Therefore, the 6t3 mm diameter iatperfectioa az elevation 9257.5 fee[ cane rerun with 2t1 mm diartterer imperfections a[ higher elevations (one per sore, on the average), These probability curves of flow ventts head ace presented in Attachment 9. This group of curves appears to represent the field data quite well. in addition, a configurations with a 7±3.5 tom impertiution located in flu third interval (a[ 9257.5 ft) and 2 t 1 tam imperfections at higher elevations, and with only the 713.5 mm iatperfectioa at the third interval were among the wmbinatioru checked. The graphs for these two wnfigtuation are provided as Attachrttents 10 and 11. While these graphs appear ro move the observed points to theoretical curves representing even ]ower probabilities than other, they does not seem, as yet, to reflect the empirical curve itself. Therefore, these are only preseata:d, now, as examples of the analyses performed. In summary, the best fit to the current data base identified to date is the bt3 rnm sinpJe defect. However, in rcxoguirion of the low pregnant solmion head oavrring ro date, CC&V hag selected the 6t3 mm + 2t1 tt~ configura[ioa for itc cheek of pump design. To reiterate what is likely obvious a[ this point, lhase computations ruing [he current LVSCS Phase II data have been performs! to assess the adequacy of the excess pumping capadty of the LVSCS Phase II system. As the EPA points out, if the drainage capacity ntezts or excewds the inflow rapacity, the system is acceptable. Once a good representation of the deplnytoem of the imperfections has btxn developed, u has been accomplished with the resttJts reported above, the flows that aright be anticipated [o develop as the pregtunt solution head ia.~reasnl may be better estimatsl. For example, if flows expxted for the configtuaiioa of the 7 f 3.5 tom imperfection az dre third elevation interval of the PLS, with no other imperfections, are examined, the flow raze az the 97.5 percent confda;. _ce intorval and xt the tnazimum pregnant solution head of 50 fee[, would be 23 gallons per minute (gpm) (Attach~sunt 10). To represent the eonfigttration that likely exists and to be conservative lry assutoing itnperfec[ions exist az higher elevations, CCc$V selected Ilte configuration of the 6t3 nun imperfatioa at the sewad imerval elevazion with 2f 1 rnm defects !Dental at higher elevations. The flow rate at the 50-foot head would be slightly less than 21 gpm (Attachment 8). Of course, it is unlilnly that the ftd150 fool head would be reached, bocattse this is the maximum height that mould be physically achieval within the desig»ated PLS of Phase II and it would involve excessive inventory of gold in the fluid phase. CC&V employs, at present, two pumps in each LVSCS. These ptarqu are installed in separate riser pumps located relatively close to each other. They arc EPG Model TSP 3-9 (aka WSI)PT 3-9), electrically powered (lhp), submersible units designed for side slope riser leacha[e removal. The pump curves ue attached (Auechmen[ l l). The static head to be overoomc az the Phase I[ area is approximately 65 feet. Aewrding to tha pump curves dccxibing these TSP3-9 ptunps, the capac:iry of wch of the pampa az heeds on the order of 100 feet is about 2't gpm. As such, these pumps arc adtquate for presertt and projected pumping. CCBcV has investigued othu pump arrangements that would locrnse the pumping eepseiry in tarots u dte flow n[e should such additional putuping capacity be required. Far example, the same manutacttue can supply the TSP3 model in other larger configurations that would increase the flow rete. Also available are TSPS and TSPB tnadela.