Laserfiche WebLink
<br /> <br />Vertical Hydraulic Conductivity Measurements in the Denver Basin, <br />Colorado' <br /> <br />PETER E. BARKMANN' <br /> <br />1. fI.\dnus.cripl rKt'i~ed St>plembt-r 1, 200~; Accepted Seplembt>r 17, 2004 <br />2. Coloroldo Geological Survey. 131] Shftm,Jn, Room 71 S, Denn-f. CO 80203; e-mili!: P""'('f_bar~m"nn@~talC_CO,u~ <br /> <br />ABSTRACT <br /> <br />The Dcnn:r Basin is a stnJCtu.J.1 hasin on the (.'astern Hank of the Rocky .\loLlnlain From R.1n~e. Col- <br />orado, comainin,g approximately ';000 ft of scJim{.'ots thai hold a critical groundwater resource supplying <br />man)' thousands of households with wakr. .\tJnaging this groundw:ltef rl.'.,>ource requires understanding <br />how waler gets into ~lnd !TIO\"e.s through warcr-tlCaring IaYl'fS in :1 complex multiple-layered sedimentary <br />.sequence. The Denver Basin aquifer system consists of pt:'rmeahle sandstone interbedded with impermc> <br />able shale that has been sulxJivided info fOllr principle aquifers named. in ascending order, the Laramie- <br />Fox Hills, Arapahoe, Denver, and Dawson :Iquifers. Although sh:l]e can dominate.: Ihe stratigraphic <br />interval containing the aquifers. there is \'Cry Iinle empirical data regarding Ihe hydrogeologic properties <br />of the shale layers that Control groundwater flow in the nasin, The amount of watt'r that 1100\-S vertical]y <br />within Ihe basin is limited by the \'ertica] hydraulic conductivily through Ihe confining shale layers. Low <br />\"t'rtica] flow volullles Iransbte to low natural rech:lrge rales and can h:n'l' a profound neg:Hive impact on <br />long-term well yit'!ds and the t"conomic viahility of utilizing [he resource. <br />To date, direcl measurements of \'enical hydr:lUlic conductivity from ("ores of fine-grained sl'uiments <br />have been published from only five locations; and tht;' dala span a \viue range from lxlO':\ to lxlO"lt <br />cm/sec. This range may he auribuwb]e, in part, to differenn:s in sample handling and anal}lical n1t:'th~ <br />ods; however. it may al."o reflect suhlle differences in the lilhologic charackrislics of the tine-grained <br />sediments such as grain-size, cby mineralo,t.::y. and compaction that rehlle to position in lilt: b:hin. These <br />limited data certainly call for the collection of additional data_ <br /> <br />INTRODUQION ........................ 169 <br />THE DENVER BASIN AQUIFER SYSTEM . . . . . .171 <br />GROUNDWATER FLOW WITHIN THE <br />DENVER BASIN AQUIFER SYSTEM. . . . . . . .173 <br />VERTICAL HYDRAULIC CONDUQIVITY <br />MEASUREMENTS ........... .1 in <br /> <br />Kiowa Core- <br /> <br />...............177 <br />.... .179 <br />. .180 <br />..... .180 <br /> <br />SainIVrainCore........ . <br />Caslle Pines-Core........... <br /> <br />... .177 <br />.177 <br /> <br />PiHkerCor{' <br />SPDSSC()r{'............... '-.... <br />DISCUSSION.. . . . .. .. .. . <br />RECOMMENDATIONS FOR ADDITlOi\:AL <br />DATA COLLECTIOi\; ..... ........ .182 <br />REFERENCfS -.... .............. .183 <br /> <br />1"'~ODlTCJ10:'lo' <br /> <br />of thou~:md... of hOlN...hokls ......ith wah:r, E.'\tt'ndin~ .south <br />from Gn.-eley to Colorado Sprin,!.:." :md L~.hl from GoldL'n [0 <br />Limnn. thL' fkn\'er j.::roundw;lter h~l.~m Covef', ;10 are-a of <br />nt':lrly 67(X) mi2 (fi~_ ] J. Encump;\s~mg l1111lh of tIlt" [kmer <br />ll1l'tropolit:m rt'gion. lhe water rl'~)lJrCe within these basin- <br />fill .'>L--uiment-. i... bL'in~ IIlcn.-.I"inJ.:ly t:Xploi[("d. particularly <br /> <br />l1w Den\'er Basin i... a ~rul1ural h.lSin on thL' e:blem tbok <br />of the Rocky ~founuin Fmlll R30~L'. In t':htem Color.ldo. <br />approximately .3000 fl of stx1ion within thi,~ ....rnK1ur.11 hasin <br />hold" a lTitical groundwater re.sourCt. that :-.uppht:'s hundrl--u" <br /> <br />Th".lfmmf{j"'(*'>ioRL\t.v(~ '11:"" ~(0<1,*-'cr2Ol}lJ.pt()<)_Jl'_~ <br /> <br />169 <br /> <br />Th... R,~ k} \l<>unl.J.m ."--~..xj~\if>n of (;etJlo~l:'>l-' <br />