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<br />I SENT BY: BOR-WCAOS SO; <br /> <br />0=-"-".- __~ - --- -"".'<.. <br /> <br />... ,... ....., <br /> <br />,............. <br /> <br />8-16-96 4:51PMj 970 385 6539 -> <br />.:. eOfl.WCAOI 80: 'UI <br /> <br />303 866 4474; #15/22 <br /> <br />SWQBINMED SIIIIUIl81'Y <br />August 12,1996 <br />Page 13 <br /> <br />chronic ~ for total recoverable selenium as wdlu ~ng the State's bistoric criterion for <br />this pol1uWlt, This table also indiCIlW that return flow from the AninWJ-La Plata Project, which <br />wov1d be fluther enriched in this polluwlt. will have strongly adverse impacts 011 the water quality <br />oftbe La Plaia River, <br /> <br />Tables L.l throuah L.3 (Paaell R-122/126) These tables campare coneentrl&tioDs of various !race <br />elements pmU;ted by tile model for current 'Onditions with aauallevcls of contaminants fur !be I.a <br />Plata RiVC!ll' during tho monthi of May, August and November, They show, that for the New Mexico <br />La Plata River stll.tioas, the model cOJlSistently ~stimates \:Oncenllations of TDS and !race <br />e1.ement5,1iequeotly by large marains. The$e tables III1derestimaw ~t levels of selenium by 11& <br />much as 93 pexcent ILlld TOS by u much lIS 81 percent. Predicted levels ofmertury are frequently <br />overestimated u much as 21 S pel'C1mt. It is WlY disturbing that, after demonstratins how poorly <br />the model predicts current conditions. the Bureau of Reclamation bases all predk:tions of future <br />contaminant levels on this model. <br /> <br />Tables L-4 through L-9 (pages 8.128/139) These tables compare concenlrations ofvarlousllace <br />elements predicted by the model for PhL'IC T, Stage H and Phase n with levels of cont.arDirw1ts <br />currently predicted by the model for the La Plata River durina the months of May, August and <br />November. Since the projections of current levels have already been dem.onsllated to underestimate <br />actual selenium levels, no real credence can be given to these predictions. <br /> <br />Table SJ.3 (page 8.155) This table shows the La Plata RivCI' irrigation return flows and the <br />predicted peak Jelenium loading, This table IlIsumel that retum floWll will iw:rcase in volume, but <br />not in selenium concentrations, /J collt:1UJiollll1111cllls JWt scientifically dtfeltfible. When the <br />predicted return flows to the La Plata Rive in New Mexico increase by lSS percent, the lotal <br />selenium 10adiJIs increases b)' onl~. ] 24 per=rt (the increase in return flows and loading do not <br />agree because SOXlIe of the IetW11 tlows with lower levels of selenium will have the greatest <br />increases). It would seem that the levels of selenium would also increase in the return flows, <br />particularly from tho!le lands Dot currently W1der irriaation, These predictions appear to be besed <br />on SOIIIC t'uturc predicted equilibrium conditions but do not consider the impacts caused before such <br />equilibrium OCCUlS. <br /> <br />From 1992 to 1994 BlIl'e&U of Reclamation conducted investigations into the projected SIllcnium <br />problem to be caused by the Animas-La Plata Project. Soil, sediment, groundwater, surtace water <br />and biological samples from Proj~ lands and the La Plata River Wlln ooUe$d. "Whit. noting <br />intermittent occutl'Cl1l:el of elemed selenium concentrations, the investigations did not dillCOver <br />levels of COIlfaminanls that would cause widClplC8d lwardous or toxic retum floW$. Nevertheless, <br />since the 1991 DSFES, 1,512 acres of full-service lands have been eliminated from the Project <br />because of their potential to aft'ect water quality in the La Plata River from selenillD1loading." In <br />ather wOlds, although they clon't see a problem with selenium, they are tryiDa to miti.p.te that <br />problem. Ineidonta1ly, lIloJ"tIIe lands removed from the Project are in New Mexico. New Mexico <br /> <br />,"' <br />'rn <br />