ML20151C643

Forwards marked-up Pages of Technical Rept, Redox State of Cedar Mountain Formation Aquifer,Green River Umtra Site,Ut. List of Questions Asked by M Young of Contractors at Pnl Was Appropriate & List Complete

ML20151C643
Person / Time
Issue date:	07/07/1988
From:	Ballard R NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
To:	Surmeier J NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
References
REF-WM-68 NUDOCS 8807220074
Download: ML20151C643 (2)

Text

{{#Wiki_filter:, _ + r' 3 JUL 7 1988 GREERIV MEMORANDUM FOR: John J. Surmeier, Chief-Technical Branch, LLWMD-FROM: Ronald L. Ballard, Chief Technical Review Branch, HLWMD -

SUBJECT:

REVIEW 0FLTHE GREEN RIVER' RAP TECHNICAL REPORT ON REDOX CONDITIONS As requested by Michael Young, the geochemistry staff has reviewed the technical report entitled, "Redox State of the Cedar Mountain Formation Aquifer, Green River UllTRA Site, Utah." The purpose.of this review was to determine if the list of questions asked by Michael Young of his contractors at PNL (B-2483) was appropriate and complete. The geochemistry staff concluded that the questions are appropriate and the list is complete. Attached nark-up pages of the technical report which contain the geochemistry staff coments were provided to Michael-Young on June 24, 1988. In addition, a meeting attended by David Brooks, John Bradbury, Tin Mo and Michael Young was held on June 24, 1988 to discuss those comments. In that meeting, the geochemistry staff pointed out to Michael Young that although the DOE has attempted to determine redox conditions from numerous couples, many of the couples provide no information to constrain the system. Couples in which the reduced species were below the detection limit can indicate more oxidizing conditions than those depicted in Figure 3.1 of the report. Approximately half of the points plotted in Figure 3.1 fall into this category. The staff noted that reducing conditions are not demonstrated in either the Dakota sandstone or the upper middle unit of the Cedar Mountain Forration. Both of these units will be cut by the proposed disposal site. The lower middle unit of the Cedar Mountain Formation does indicate a change from oxidizing to reducing conditions along the potential flow path. More importantly, uranium in the ambient water seems to be responding to these changing redox conditions. If you have any questions concerning this review, please contact John Bradbury at x20535 or Tin Mo at X20541. Ronald L. Ballard, Chief g

Attachment:

As stated g'R ' DISTRIBUTION 8 Central Files REBrowning, HLWM BJYoungblood, HLWM RLBallard, HLTR m J0 Bunting, HLSE JLinehan, HLOB HLTR r/f JBradbury, HLTR m THo, HLWM DBrooks, HLTR flYoung, LLTB JStarmer, LLTC 6 MKnapp, LLWMD NHSS r/f 0$ n nw

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yf bgg (fb====? ) w m\\ A' EXPLANATION FOR WORK TO BE COM p k Lf' / / / f' FIN B-2483 N~__f C [As part of Task 5 (Short Term Technical Assistance), I request that you, Jeff / Serne, and Randy Arthur review and comment on the enclosed report entitled, / "Redox State of the Cedar Mountain Formation Aquifer, Green River UMTRA Site, Utah." The comments should be enclosed in a letter report. I citima_te_that / the total maximum time required to complete the task will be three staff _ weds The letter report should be delivered to me by July 8, 1988, / ,e 2 i / The purpose of your review of this report is to assist NRC staff in reviewing the available geochemical data on the Cedar Mountain Formation, and / in determining whether assertions contained in the report are reasonable and EM l based on adequate data. I have several specific questions that,should be v Tl >' t Cem yon. $ u f addressed in the letter report: cehn (1) Were the analytical techniques used to determine the ratios for the 6 y various couples appropriately used? Qp ~ (2) What are the uncertainties associated with these techniques? Are the 7Q9 uncertainties significant in terms of the conclusions? d/29/d (3) Could an in-depth independent analyses be performed using the data contained in the technical report? If not, which areas of data collection would be most useful? Do the data support the assertions that the geochemical environment in M (4) the Cedar Mountain Formation is reducing? h h ti g p m c fcI 4 M 4 { I il .m y]QGtj (5) Will the geochemical conditions inferred from the data contribute to i reduced uranium concentrations? Which attenuating processes will likely dilution, precipitation reactions, etc.)? ' 4< ) reduce uranium concentrations downgradient of the cell boundary (i.e., i j (6) What inferences can be made, based on the available data, on the potential migration rates along the flow paths from well 562 to well 815 i i over the next_severalhundred years, assuming that the conditions remain i constant over time? k Please contact Michael Young (NRC PM) for any questions concerning work to be \\ performed under Task 5, or if more information is needed to answer the above questions. 6 f~, yAL. *. gQ w sp cend k "Y n' cta er rc%u;[ @[ j 3 s*)a v OMTRA*E t & L - Scuy ( f W ) ]q, y 4J29/eg

UMTRA-DOE AL -400641 .0000 United States Department of Energy ' ~~ c s REDOX STATE OF THE CEDAR MOUNTA;N FORMATION l AQUlFER GREEN RIVER UMTRA SITE, UTAH TECHNICAL REPORT l l i L i I l June,1988 A sk o

in Uranium Mill Tailings Remedial Action Project. M1.IJAPl 60 (

1 860608 WM-68 DCD

RED 0X STATE Or THE CEDAR MOUNTAIN FORMATION AQU!FER GREEN RIVER UMTRA SITE, UTAH TECHNICAL REPORT JUNE, 1988

I 1 t TABLE OF CONTENTS e 9 Section g

1.0 INTRODUCTION

1 2.0 S AMP L I N G AN D AN AL Y S I S...................... 2 3.0 RESULTS M0 DISCUSSION..................... 4 4.0 SU MMR Y M0 CONCLUS ION S..................... 6 REFERENCES........................... 19 i

3 -LIST OF FIGURES Figure Page l ' 1.1 ' Location of the sampled monitor wells and location of hydrostratigraphic cross sections-.......-.. 7 1.2 A north-south hydrostratigraphic cross section .............8 through Green River, Utah, tailings site 1.3 An cast-west hydrostratigraphic cross section througn Green River, Utah, tailings si te............. 9 1.4 Potentiometric contrJr map and monitor wells, upper-middle hydrostratigraphic unit, Green River, Utan, tailings si te, October,1987............... 10 1.5 Potentiometric contour map and monitor wells, lower-middle hydrostratigraphic unit, Green River, U tah, tailings si te, October,1987............... 11 2.1 Plexiglass flow-thrcugh cell (c) used in on-site measurement, and collection of contamination-free water samples......................... 12 3.1 Calculated Eh of redox couples.... 13 3.2 Field Eh vs calculated Eh of redox couples........... 14 3.3 Saturation indices, log molality of uranium and me a su red E h val ue s..................... 15

LIST OF VABLES L Table Page 2.1 Concentration of redox-sensitive ions, and ratio of re d o x c o u p l e s......................... 16 2.2 Concentration of selected major, minor, trace elements and ions........................... 17 3.1 Distribution of uranium in the Cedar Mountain Formation aquifer. ............ la iii 1

e S J The presence of pyrite and organic matter in the Cedar Mountiin g Formation aquifer of the Green River site indicates that tne groundwater at s tne site may be reducing (DOE, 1988, 1987); and therefore, redox-sensitive \\ elements suc'h' aTuranium would orecipitate from groundwater withi g [gw { ~ hundred feit hydraulically downgradient from the proposed disposal si te. fhe purpose of tnis study is to substantiate tnis ob servati on by determining the redox condition of the Cedar (tountain Formation aquifer directly. Redox potential (Eh), dissolved oxygen, and a suite of recox b 2 5 3 /5 As As +, N0'3/N0~2, 50 4 NO '/NH +, and NO /NH4) 3 4 2 were measured directly in the water samples collected in May,1988, from the Cedar Mountain Formation aquifer. This report summarizes tne results of tne groundwater redox measurements. The Green River VMTRA site is shown in Figure 1.1. Tne hydros:catigrapny of the Green River site area is discussed in the Green River Remedial Action Plan (RAP) (DOE, 1988), and is sumnari zed in Figures 1.2 tnrougn 1.5. The upper-middle hydrostratigrapnic unit of the Cedar Mountain Formation is mudstone or shale with occasional thin and discontinuous calcareous beds (Figure 1.2). The hydraulic gradient in this unit ranges from 0.0063 to 0.0063 ft/f t. The fjbw of groundwater in this unit is controlled by fractures, joints, and faults. Tnese fractures, and f3Ulti are contihiioils 7 thYogh ~~'the7we r -m1 AdIe_ 3)Me un W ipte5 W 7 W W is TITte rb e dGF6~wi th tne upper-mid e uni t. T he lower-middle unit consists of ~ sandstone

and_,

conglomerate.~Tne jower-mTTdle.__un~iCis primarilyflo_w. con fisedlinea thTtne_ . n ilings ~ iFea. Groundwater within this unit s under a hydraulic TFadient7dniing from 0.0083 to 0.025 f t/f t. Tne potentiometric surf ace (Figure 1.5) in tnis unit is two to three feet above tne surface of tne tailings at monitor well 581 (Figures 1.2,1.3, and 1.5). 1 6 1 1 l \\ \\

2.0 SAMPLING M0 MALYSIS Groundwater was sampled from the upgradient wells 562 and 813, on-site wells 701 and 581, and downgradient well 584 in order to examine the redox cnaracteristics of the upper-middle and lower-middle hydrostratigrapnic units at the Green fliver site. Figures 1.2 and 1.3 show the perforated zones of the sampled wells. The upgradient wells 562 and 813 are perforated in botn the upper-middle unit and the-interbedded lower-middle unit. The on-si te - well 581 is perforated only in tne lower-middle unit; well 701 is perforated in the portion of the upper-middle unit that immediately overlies the lower-middle uni t. The downgradient well 584 is also perforated -in tnis part of tne upper-middle unit. Samples were collected by pumping water from th' e well s tnrough a plexiglass flow-tnrough cell (Figure 2.1) ensuring no headspace existed within tne cell, in order to avoid atmospheric contamination of the water wi tnin the cell. Temperature, pH, platinum-electrode potential, dissolved oxygen, and specific conductance of water in the cell were monitored until they stabilized and the readings of these parameters were recorded. Samples for laboratory analysis were collected in pre-cleaned bottles (glass and polyethelene) without headspace, and ware immediately cooled by ice and transported to the analytical laboratories (United Nuclear Corporation Lab in Grand Junction, Colorado, for analysis of redox couples and Barringer Lab in Denver, Colorado, for analyses of major and minor, trace el ements, and certain ions as shown in Tables 2.1 and 2.2). Laboratory analy~ses were gmpleted within 48 hours of sample collections. Alkalinity, NO and Fe were measured in the field (the latter two were al so me[3ured in the laboratory { andAlkaligity was measured by titration as calcium carbonate. The NO Fe were neasured by a

• an Ultraviolet / Visual (UV/VIS) spectrometric method.

3" 2~Laboratpry analy,ses of the ions (NO ~, PO Cl~, ckmbinatiob, of ion SO NH and S) were obtained by a chhoma,tographic, UV/VIS spectrometric, and titrimetric methods NC, 1987 ). % 4, ~~ 4 6 U+ were determined by inductively-coupled U+, and 4 - Q otal N plasmaha 3 pectromgtry ( ICP -MS ). Using the method of Sill and Williap b (1981), U and U were s'!parated prior to ICP-MS analysis. As an As ware measured by a hydride-Atomic Absorbtion (AA) metnod. As(total was determined by detersigd by the di f ference. Tota 1, Fe was 3 furnace-AA and Fe by UV/VIS spectrometry. Fe was derived from the differench Total Se, Y, and other elements were measured (see Table 2.2) by ICP Q, 198 Two geochemical models are used in this analysis, WATEQFC (Plurtner et al. 1976; Runne11s et al.,1980; Runnells and Lindberg,1981) and PilREEQE (Parkhurst et al., 1980). Both programs solve simultaneous equations that describe the equilibrium chemical reactions wtitch may occur in a given water body. Runnells et al. (1980) and Runnells and Lindberg (1981) have expanded the thermochemical data base in WATEQFC for many additional trace 1 i ~ _ j

p. m.

x

' metals,. including a majority of the dissolved species and solid compounds-of uranium and vanadium. PHREEQE was. used in this study to equilibrate solutions wi th a given set of mineral s and to compare equilibrium calculations, including speciation and saturation indices of-selected. minerals, to the results from WATEQFC. From the inout of the solution. analyses, both WATEQFC and PHREE 0E compute the activities and distribution of complexed and free. ionic species -and neutral ion pairs. The models then calculate activity products and compare tne ion activity products (IAP) to the solubility products (Ksp) for the minerals and solid corrpounds contained,in their databases. The ratio of IAP to Xsp defines _ the extent of saturation of the solution with respect to a given mineral or solid compound. 3

3.0 RESULTS AND DISCUSSION The distribution of calculated redox couples and measured field En for monitor tells 562, 581, 584, 701, and 813 are shown in Figure 3.1. The range of calculated En values is about 1000 millivolts (my) for the groundwater samples collected at the Green River site. The relative En values for the di f ferent rodox couples is consistent among groundwater sampl es, where the degreasing redox integsi ties are dissolgd oggen > NO ~/NO ~ NH /NO ~ NH /NO ~ Fe /Fe (60X, 2 Sato, 1960) HS~/S Cn Sato dissofved oxygen 3 fihd SO ~ / HS ~. 4 Field Eh masurements (Table 2.1) were used as input values for podeling calculations (Eh of various radox couples, dissolved species, and the saturation indices of various uranium minerals) in conjunction with pH, temperature, specific conductance, and solute concentrations. The field 2~etween measured dissolved oxygen concentrations and the Eh values lie b calculated SO redox couple. Determining the most appropriate redox couple th u/HS~se is difficult because interg"al dgequilibrium appare exists between the redox couples. The Fe /Fe and Sato 00X redox couples, however, are in close agreement with measured Eh values for monitor well s 562, 813, and 701, whereas the HS~/Rnombic sulfur redox couple approximates measu red Eh values for monitor wells 581 and 584 (Figure 3.2). Uranium exists in both 6+ and 4+ valence states in the Cedar Mountain freen River site (Table 3.1). Uranium js Formation aquifer at the i ~ (CO )fch (by TEQFC and PHREEQE) to occur mainly as UO (C0 ) y~ complexes predicted 3 in wells 562, 813, 701 and $84, wh and UO are mob $1e udd[r relatively oxidizing, alkaline pH conditions. Altnough subordinate to the carbonate species, the presence of U(OH) - in well is relatively significant and is predicted to be the dominhnt form of 584 dissolved uranium in groundwater samples obtained from monitor well 581. Precipitation of uranium (4+) in the Cedar Mountain Formation aquifer is controlled by Eh, pH, and concentrations of uraniua, alkalinity, hydrogen sulfide, and other solutes present. The saturation index (S.!) provides an estimate of the degree of Saturation of a solution with respect to a mineral or solid compound. The S.I. of a mineral or solid compound is given by the following equation: Activity Product (IAP) I'I'

• IO910 Solubility Product (K5p)

I f the S. I. is greater than zero, the solution is oversaturated with respect to a certain mineral or solid compound and precipitation of the mineral or solid phase may occur. Alternatively, if the solution is computed to be at equilibrium (S.I. = 0) with a particular phase, it is possible that the solid is precipitating or dissolving at a rate that controls the concentration of certain components in solui. ion. Finally, if the solution is computed to be urdersaturated with respect to a solid phase, dissolution of tnat phase may result. 4

Pote r.ti al lioitations exist in interpreting the results of tnGse mdel s. First, equilibrium is as:.umed among the aqueous species founn / tne various solutions. Sec ond, the computations will reflect inace n wr in the thermochcmical data contained in the databases.

Tnird, present in the solution, but not included in tne model, ma; misicading results.

And fourth, complete and accurate chemical e are required as model input to obtain meaningful results. In this n,4 these limitations have been minimized to the extent possible by careful data collection and analysis. The S.I s for uraninite and cof finite were computed by WATEQFC from analytical results cctained from the groundwater samples. These results are shown on Figure 3.3. Grouniser samples fro.n monitor wells 562. 813. a& 701 are l!utar3aturated with respec t to uraninbe. increfore, uranium is fikely to be-mobile in the Cedar Moun tai n Formation aquifer at tne y proposed disposal site (Figure 1.1) and downgradient towards the existing ( tailings pile. Groundwater is otersaturated with resoect t.o uraninite near mnitor well 581. Consequently, concentrations of urand um are less tnan 0.vormg/l as groundwater in this portion of the Cedar 4ountain Formation aquifer is relatively reducing. Further downgradient, t; ward monitor Well-584, groundwater is near equilibrium with uraninite. Saturation indices for cof finite show trends similar to those calculated for uraninite. Oxidized uranium mineral s, including rutherfordine, schoepite, carnotite tyuyamuni te, and autunite, were predicted to dissolve Meause groundwa r is undersaturated witn respect to these minerals, a xw h e%p 4 L W. Y.t." baal & dye; 5 ~ +

4.0 SUFNARY AND CONCLUSIONS Groundwater samples obtained from monitor wells 562, 581, -584, 701, and 813 we e analyzed for redox couples including tnose of nitrogen, iron, sulfur, uranium, and arsenic. Groundwater samples obtained from monitor wells 562, 701, and 813 are rela tively oxidizing based on measured and calculated En values. Based on model calculations, uranium in tnis upgradient - area including the soutnerg, portion of the tai 1,ings pile is 4 UO (C0 ) and U0 complexes undgM the relativelf(C0 )$ zing, alkaline likely to occur as ox$d 2 that are li4 bile in groundwater conditions. Conversely, groundwater samples obtained from monitor wells 581 and 584 are relatively reducing based on measured and calculated Eh 1

values, ne presence of hydrogen sulfide, and the less-than-detectajLA.

J concentrarions of uranium ( <0.001 mg/1). Groundwater is predicted to be oversaturated with respect to both uraninite and coffinite beneath the tailings at monitor well 581, and near saturation at monitor well 584 The relatively reducing conditions in the upper-middle and lower-middle hydrostratigraphic units north of the monitor well 701 and downgradient (westward; see Figures 1.4 and 1.5) appear to be controlled by the naturally occurring hydrogen sulfide detected in the monitor wells in this zone. T here fore, the relatively reducing conditions noted in upper-middle and lower-middle hydrostratigraphic units of this zone are natural and will continue to attenuate the redox-sensi tive dissolved species such as those of uranium and nitrogen. The results of this study support the contention presented in the RAP (DOE,1988) that dissolved uranium and nitr, ate will be attenuated within a few hundred feet downgradient of the proposed disposal and the non-remediated tailings sites, i Thi s study' demonstrates that carefully measured pl atinum-electrode potential is useful in estimating the redox state of groundwaters. Furtner, the results show that the redox couples may be used to check the estimates of redox state by platinum-electrode measurements. 5 e -6

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~ 2_ 2. 585 b4054.7 g" N g',p x [ r e. s v.w g 3 r AILINGS PILE / g / g f 0 '\\ <* 8 4049.6 4 +09 -.::y', .ose u , (I JL N ~/ .i ,) C LEGEND h ~~--w-FENCE e, r,' =n="*** 6 ( l C M;LL DUILDINGS gt yggn r .co Ib WATER s LIGt:T DUTY ROAD e noo II ( '- , g*s.o DIY8< l -- JEEP TR All e[ /,f f ""~ EPHEMER AL STREAM 40 ( J \\ s' l l >f >,'N s' l // 701 I e4 cst., MONITOR wet.L. WELL ll ACT / ) l a s s.=", NUMBER. AND WATER LEVEL i I l a' [f ELEVATION IN WELL i10f 8Tl 40% \\ ~f p)* DRV 4<4057.08 816 8 -4GCC" POTENTICMETRIC CONTOUR l'4083.8 e s g!y 2 AND ELEVATION (DASHED g j a a,,.. / .I f WHERE APPetOXIMATE) I l %,( 408 \\, d',5 lf PROPOSED I( k' DISPOSAL SITE N I ,,6 4o. s ? 200 0 200 400 600 SCALE IN FEET FIGURE 1.4 POTENTIOMETRIC CONTOUR MAP AND MONITOR WELLS, UPPER - MIDDLE HYDROSTRAT! GRAPHIC UNIT, GREEN RIVER, UTAH, TAILINGS SITE, OCTO8ER,1987

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M 3R . Ii %fhh?k j [ }},8.sAf' s g 0. ...~:. A..

?C.

m- .A SN k 1:g ? f ,r L 4 / i 5 1 i l l 1 FIGUHE 2.1 PLEXIGLASS PLOW-TliRol1Gli CELL (C) USED IN ON~ SITE f/:EASUREMENT. AND COLLECTION OF CONTAMINATION-FREE WATEFl SAMPLES 1 __ l l l [

-4 ~ (-0.133VI-FIELD Eh (- 0.13 3 VI -2 kSATURATION INDEX FOR URANINITE - 1 \\ ~5 - 7 j f ( OVERSATURATION (4-o.cavl 0 T \\ yy U NDERSATUR ATION \\ - -1 g \\ 1 -6 \\ - -2 \\ z I D' - -3 S I- '\\ O H h. h k --4 a g -7 \\ e --5 O 8 ( O '2 r 2 VI --6 \\ l -8 - -7 \\ p \\ ~~ SATURATION INDEX F09 COFFINITE 274V3 -O 'c 274v8 __g _g i i A 584 8 ( 813 562 MONITOR V! ELL FIGURE 3.3 SATURATION INDICES, LOG MOLALITY OF URANIUM AND MEASURED Eh VALUES

O e O e 1.0 3 0 0

0. 8 -

0

0. 6 -

g; 'WC C. < ~ O pom ts a.c-s my qJ, A se db O ( O O 0.2 - g g) spi % -g w+t o-dD h, " '.* _ 0.,_ 7 O [oox 6] o /f ,. # m %, o -, 7 2-.,- en p. gg. - 0. 4 - a, ua;iNo2-x r.n r.2 i. 55c M O FIELD Eh usa ~1 = o* elad,0.. ves>se - ~// GL 's vay[ d oder Yk - 1. 0 [o w SQ [g 584 581 701 813 562 k=4 .WELL NUMBER ph D T' k"' # '~~' "M - FIGURE 3.1 CALCULATED Eh OF REDOX COUPLES

l In i s ,. x e e n u. t0 8 6 G oon z z g! o mix % o O x,.'v^ g O e m sN +' J o x 4 tj EQQ (/) 9 e p s o z z z. u. exz m 4,, s e 5 4 41 :< O O m > g %c O + $P

1. +

W g a: 3s 4 e O EE Wieu GID MB D 5 ci.c O NW N6 y a: +o D Q v> cW 5Ek 2 J c D o J O W .J w o e N x0 E o O 5 >44 O GM ~ m> N- .g: W QJ W e " d t I I I I I I I I i i i i y N o N T 6 6 6 6 6 + + + f I (110A) 37dOOO XOO3H WOUd 0310dWOO L43.

&' Q ( j & ' * % b, / M &J Q ~ TABLE 2.1 Concentration of redox-sensit'i'v6' ions and ratio of redox couples LabokaTOsY HEA5usDOis Total isal Total g .a 3 -3 50 +2 s-2 a,... 3.s+a 3+3es swa 26== 3== 3 saa s=1a 7d3 7.+2 o c+s c'8 mort no2 4 a-cumb.c os/1 soll mo/l c:/l ee/l ac/l ag/l g/l sc/ os/l w/l w/1 w/3 g/2 ag/l ec/ <s. m ss2 uma c.c:s <s.es e.sn s.sta e.us ici s.ss <s.: aina <s.: <a.ses <w.us e.2 <s.si s.e 2ssa si.1 <s.us su nen2 <a.s:c <o.c3 <s.een <s.us e.2 <s.si s.s nas <e.: <s ass see naru a.sas <e.ca <e.n 7ai issna 0.sas <s.s3 2.ss 1.ss s.see isia s.si as.2 @ <s.: <s.us <s.scs t:3 12c2ss o.ess (e.s3 s.sts 0.afe G.se; 22.7 a.se <s.: ars, s.:

s. sic

.se3 .m

e. sis a.ca c.cs; REDOX COUPLES (RATI IM g/l/gf3)

NO -/ Ac+3 p+5 oo m2y 180 7 - Fe+2 Sg4 / -2 y Semple U+6/ /*3 3 3 Fe 04N *I Mumber U*4 S-2 NO2 4 As g; 582 238281 7.78 156 -+- .25 Sat 138262 312" .33 584 138263 5400 34.7 .003 701 13a284 3.38 84.8 22400 3.C7 013 138265 8.75 35.3 FIELD BEEASUREMENTS er Samplo pahoe/ce* Temp Alkalinity eN'* D.G. 7e*2 802 av cg/l eg/l og/3 Number pH Ec

• C ag/l as CACO 3 962 238281 6.88 7450 16.5 660

+274 0.6 <3.1 0.8 $81 138262 7.25 5980 15.7 979 -133 G.3 <0.1 <3.C3 S54 138263 7.96 617G 15.9 264 - 30 0.2 <0.1 <3.03 701 138284 8.68 6480 16.5 407 +272 0.0 (0.2 0.05 '313 338265 8.88 7610 17.5 671 +274 0.4 <0.1 1.0a

• Corrected to 25 *C
  • Values correct for temperature and are referenced against the normal hydrogen electrodo
    • Sample preserved with MCI
      • Sample cooled only

a Table 2.2 Concentration of selected major, minor, trace elements and icas Well #701 Well #584 Well #813 Well #S62. Well #581 Element /lon conc. (m9/1) conc. (ag/1) conc. (m9/1) conc. (ag/1) conc. (og/1) Al .23 .06 .19 .21 .04 As .015 .008 .016 .010 .019 B .71 .65 .83 .82 .85 8a .01 .01 .01 .01 .01 Ca 520. 46.7 253. 328. 22.1 Cd .045 .052 .053 .072 .036 C1 94. 130. 130. 150. 160. i Co .03 .01 .02 .02 .01 Cr .18 .03 .09 .12 .01 Cu .02 .01 .01 .01 .01 T .77 1.73 .95 .85 1.12 a -a re .16 .06 .08 .11 .01 Hg .0012 .0002 .0002 .0014 .0027 X 20.5 3.27 7.24 7.39 2.51 Mg 197. 13.4 114. 124. 8.83 Mn 2.18 .03 .17 .47 .01 Mo .09 .01 .13 .07 .02 Na 1150. 1630. 1910. 1870. 1680. Ni .01 .02 .05 .05 .01 Db .02 .03 .02 .02 .09 PO .3 .3 .3 .3 .6 4 5 .1 .1 .1 .1 45.4 Se .549 .112 .134 .160 .095 SiO .0 9.2 9.2 9.7 8.8 2 50 87 3150. 4200. 4330. 2460. 4 Sr 7.82 3.50 9.55-8.83 2.60 TDS 6680. 4930. 6920. 7190. 4630. V .08 .01 .04 0.0402 .01 Zn .018 .005 .006 .006 .017

-Table 3.1 ' Distribution of uranium in the Cedar Nountain Formation. aquifer .a N Field Field a um Dominant. Eh(v >pH (mg/1)' form 4' 6.88' +0.274 0.076 UO (C0 )3 2 3 7.25 -0.-133 <0.001 U(OH)5 4' 7.% -0.080 <0.001 UO (C0 )3 2 3 [U(OH)Sl 6.68 +0.272 2.69 UO (C0 )2 2 3 6.88 +0.274 0.079 UO (CO )3 2 3 i - -, _ _ _,.. ~

~ ~ REFERENCES 00E (U.S. Department of Energy), 1988. "Rcmedial Action and Final Design for Stabilization of Inactive Uranium Mill Tailings at Green River, U ta h," UNTRA-00E /AL-050510, GRNO) prepared by the 00E for the UMTRA Project

Office, Albuquerque Operations

Office, Albu querque,

New flexico. Parkhurst, D.L., Thorstenson, D.C., and Plurrmer, L.N., 1980. "PHREEQE-A Ccmputer Program for Goochemical Calculations," U.S.G.S Water Resources Investigations 80-96, Washington D.C., 210P. Pluroner, L.N., Jones, B.F., and Truesdell, A.H.,1976. "WATEQF-A FORTRAN IV version of

WATER, a

Canputer Program. for Calculating Chemical Equilibrium of Natural Waters," U.S.G.S. Water Resources Investigations 76-13. Runnells, 0.0. and Lindberg, R.D., 1981. "Hydrogeochemical Exploration for Uranium Ore Deposits, Use of the Computer Model WATEQFC," in the Journal of Geochemical Expi, Volume 15, pages 37-50.

Runnells, 0.0,

Lindberg, R.O.,

Lueck, S.L.,

and Mark os, G., 198U. "Applications of Computer Modeling for the Genesis, Exploration, and In-Situ Mining of Uranium and Vanadium Deposits", in Rautman, C.A., ed., Geology and Technology of Grants Uranium Regions, 1979, New Mexico' Bureau of Mines ano Mineral Resources Menoir 38, P355-367.

Sato, M.,

1960. "Oxidation of SulfideI Ore Bodies, 1. Geochemical Environments in terms of Eh and pH," Econ. Geol., Volume 55, pages 928-961. Sill, C.W. and Williams, R.L., 1981. "Preparation of Actinides for Alpha Spec trometry Witnout Electro-deposi tion," in Analytical Cnemistry, Volume 53, pages 412-415. ' NC (United Nuclear Corporation), 1987. Handbook of Analytical Methods, Rev. OU. E / / ghk lot [ 7d 24^- U LLM cva dtr W & k & tad wnspos - AL-ro,89f enyv-.# e% @ , " &A n gL 4 ma yd M, z q.xyxuan,- s o % di ) p ddn d ac " a 08 " N l g L_.}}