Laserfiche WebLink
•~- <br />t <br />~ :I ~~' atC\~ ,~~:,I~ <br />} '~,i?x{3G~ _ _ ~NG1~fE:_z~ E~IVIF_r:'-~~aTAL SCIENTISTS <br />Tiny 29, 20> 1 <br />I~?I:s. Rebecca Hang <br />City of EII{ River <br />~rivlronn}ental I~ivlsiotZ <br />13065 ~3roa~t~ Parkway <br />EIk River, SIN 55330 <br />IZE July 2U11 Greuud~~vater IVrajtifori>;zg Results <br />Oicl City Duznp, Elk Itivej~, i~~Iinries~ta <br />Dear Rebecca; <br />Enclosed. please find the 2t~11 annual water gtaalit}j data. fc~r tiie Old' EIk River Dtttnp site Iocat~d <br />so~itheastof the City flf Elk River (Ff~ure 3), ?tie grotand~vater sampling eras c©n~pleted ~n July <br />l~, 2011 by Liesch Associates, Inc. {Licsch). Saanple locations inckzded_monitoring wells I~1W~2 <br />atld M1~-3 near Elie forrn,er City duanp site {Fi~;tire Z). <br />M-i forn~erl~ located north of the dump «; asscaled iit_2~02 when a parking lot for th.e~c:it~~arh <br />vvas coi~stX~ucie~~i ia~ the- area 1~e ~~~ell wns l~~ated. (aver #~n-y~ea~rs t~£ va~t~r +~nality m~oi~it~7-iiz~ at tiar~s <br />tip-gradient tit~eil locafoai ev%denced uo detectio~ls ol'VOC's therefore the well was not replaced. <br />Laboratory results of the June 2011 samhlir7g event (T'at~le ~) indicate`lo~v Level VUC detecti.o~xs of <br />Tetrachloroethca~c (PCE) in MVO'-2 anti Trichloroethene {TCE} in M~~-3, PCE was detected in <br />i~'1L~~-2 at a Level of l.4 parts }qtr ~illio~~ {I~hI~) a~ICi TCE teas detected ial ~I~V-~ at a Iev~l ofl.l pt~b. <br />The VCs detected duritl~ the 201 I sanlplin~ event are corisisfent with histoa~ic low coalcenta~atioaas <br />fi~:and in grouud~vater saa7~ples collected fi•oan 1~11~-2 <~aid MW-3. <br />Vdafer level data indicates that the w°aier fable at il~e site a~ei~~ains col~sistor~t with water levels <br />recorded over that last ~ years (attached ~~'clt H~~dl•ogi~apl~). Gro~nldwatcr l1ow direction co~ild a~ot <br />be calculated as a aninin~um of tt7ree anoniforiaig points are needed for this detern~ia~atioa7 and M~~-I <br />~~~as sealed. Historic ~ronndwater fio~v direction? for the site has teen. a st~~athtivesterly direction, <br />towards tl~e Mississippi. River. Presumably this has not changed. <br />,lhe VOC concentrations at the ai~onitoring well locations {M~-~ aa~d M~'J-3) have been relatively <br />stable over fhe last few monitol•ing events. TCE was not defected in MW-3 in 200.5, 200? and 2009. <br />bnt has been hi tonically det~eted since 1989 at deca-easia~g levels. PCE levels detected in MW-2 <br />have remained relatively static since 1989, PCE and ~'CE concentrations are cunnently below <br />Minnesota Department of Health (MDH} Health Risk Limits {HRLs~ for drinking water. MI~H <br />HRLs for PCE and TCE are currently set at 5 ppb. Based on informati©n gathered d>.aring the 2011 <br />a <br />~.y~~+~,iiescFi.~~rrq :~, <br />~i~stt~ AssocinrES, Ilac. ~ ~ 3~+OQ i Sr11 AvEr~~uE NOR,Ti= x: ~4iNt~E~,PO~IS, MN 55441 ~= 763t489-3100 Fx FAX: 76314f39-310j <br />