ML21076A465

From kanterella
Jump to navigation Jump to search
Cimarron Environmental Response Trust Facility Decommissioning Plan, Revision 2, Appendix I, 2020 Groundwater Flow Model Part 3
ML21076A465
Person / Time
Site: 07000925
Issue date: 02/26/2021
From:
Environmental Properties Management, Enercon Services, Burns & McDonnell Engineering Co, Veolia Nuclear Solutions Federal Services
To:
Office of Nuclear Material Safety and Safeguards, Cimarron Environmental Response Trust, NRC Region 4
Shared Package
ML21076A479 List: ... further results
References
Download: ML21076A465 (24)


Text

FIGURES 2086400 2086800 2087200 2087600 2088000 2088400 2088800 2089200 2089600 2090000 2090400 2090800 2091200 2091600 2092000 2092400 2092800 2093200 2093600 2094000 2094400 2094800 2095200 2095600 2096000 2096400 2096800 2097200 2097600 2098000 2098400 2098800 2099200 2099600 2100000 2100400 2100800 2101200 2101600 2102000 D

D N

~

D D

a, V

N D

D

~

~

D D

D V

N D

D

~

"O N X

E r--: D x D N

"'~

~

I I

C 0

~ u 0

.,_J Cimarron Prope I

~

in I

Ol u:::

cC\l a:

Ol

-~C T-66 0

"iii T-70R CJ)

.E E

0 u

Q) 9 LO 0

N cii u

0

-0 E!

u:::

I 0

(.)

~

aJ U) a ~

i:

CJ)

OJ

~

0 CJ)

I

.9 0 oz

..c-

a. >-- Figure 1-1

<l>lz Cl..,;(

Ill 0.:

~~

LOCATION OF CIMARRON SITE

~8

~(!)

<l>Z 2016 GROUNDWATER FLOW o-Q) er::

(!)W MODEL UPDATE

---w 3l z ro-

..0 (!)

roz

~ BURNS

" -M!:DONNELL.

~

environmental row 9 miles f'ff J'J *J*. rr 1.,.1'"', *11 0--l

--- .,_J gjw

""Z

~z Legend

.E 0 co

0

~~

=<>11 - SITE BOUNDARY

(.) CJ)

---'er::z I- 1050 Topographic Contour and Elevation cr:: ::>

~ aJ N s~ 0 250 500 1,000 Zo WN i?@

c3 CI-

-~ :I:

(!)

Feet Source: ESRI and Burns & McDonnell Engineering.

A Service Layer Credits: Copyright:© 2013 National Geographic Society, i-cubect

~~

..c a.

COORDINATES: (NAD 83) STATE PLANE OKLAHOMA NORTH FEET roO DATE: AERIAL PHOTO - 2010 I MAP PRODUCED - 116/2017 a.(.)

2086400 2086800 2087200 2087600 2088000 2088400 2088800 2089200 2089600 2090000 2090400 2090800 2091200 2091600 2092000 2092400 2092800 2093200 2093600 2094000 2094400 2094800 2095200 2095600 2096000 2096400 2096800 2097200 2097600 2098000 2098400 2098800 2099200 2099600 2100000 2100400 21 00800 2101200 2101600 2102000

2091200 2091400

~

2091600 2091800 2092000

'\

- 2092200 2092400 2092600 2092800

-~~'7i""'  ;,*-

2093000

~

2093200 2093400 2093600 2093800 2094000 2094200

~  :,'* ~* ~ , * *-;,: f'g z7~05

  1. =c 1  : J._~9

, -- _.-, """', . . - *d*: 7 ' - 928.25

/ : ~-~-,~;, .-:~,:(:c,c, ,. :*~,;° ,'. . *,,, . '

~

, , *. ,:, ., .* '~:*

. J(* -

, ~:Jt.;."5

. -~ : \.' _,

~\..-}'~ ..,_; _ '-, t;;:::* '-

t "'I'_ , . ~-' ,* ~

~

&J-97,,,_

, *. ,:~: t'

  • ,ti , _ * ,

.\1 v..;, ./.~~ -..:,~ .

0 * * ~ * , ,,. ,** _, ** . _,. . l',

= ./ ."ft :,,~ ' ., - ~ ;:,;r 928 .31 ,

  • MW-13431 t .
  • _,, **~ *

, ~ -?,:, _,.,

0

I; °'
*,, ,. '"\-, ;.*J'** *

' , .~_, ,\:.i;_ ""'_f\, b;-c...,.1.f t'~~*,,.,

_,'._f.... ,'_*~ ~ -'., -- 192827 . _ . * ~/ ,,,.

~ 1 "-'

' *1 ~

928 ,78 * ** '-"- **-*- , ' "' **  ;,, ,,._ ~

-~~\ I' 5l

, .... "" -"' - .: *v I _,.,

~ ~

-2,°Q} "'- ., . .c****,_ ', ,-*~

, .. *1\.1"-,i-.t.~ -."-l

  • I \. <* \ ~- _- . . ,,.., ' .*, .. '

--~ -~.? ~

j -*

~l~

__ ~- ,

)***\_ -:-;i;.:,~t/":.

,~ ~ .- .,... -'j ....

!1 - "l .--~ ~-----_;,;=_______ 928 .5

.;. '\. *t--  : .!._. '11,'  !" ,f_J l) o 0

E ' '

'lni

' "'4-., I ,:)

," ~.

-"l*.1/-.

..  ?'"

c.:.~ "-.

~

..,T-91 h -

  • T-92R ~-.  ;**
  • . r"

.,, i, M ~ '

I,.,

< l L .. '-.*: .-,, 11- _.,._ -

! '- I 927 *63 1 (l ' *

.le.~ ,-::

925.85,

~

' . - _,, ~

, ~ *I

~.

E o

0

] ,.-"" * * ., '.:! ' T-93 T-102 - -- "-~-...; M

..., .., fsiB.661 ."u 928.69 T-89 928 .73 81 . . . ._,__ '

l~l l j * ,. . .. ' *,: -~ J ; *A . ["' . \ .. . .. ._;; ?,. 7 -' ~

~ J

  • ,u']
    • ~'\;'*,

.,*:., ,-l * 'c*'-*l ') *c ' *_-;. ,_*_ .-* * *;, l ]j, *Q ">: .,.. ,.-i ' .:"~'. .:-~*-~ g

  • I

9;,o d._, ~,.J' .J '..~. ' ,..

  • i l \:~;]" *, *;;>/ ,.;..;., .:*t O
  • ~

T-51 T-52 929.40 "929 .33

,.,, >1 * .,. --- ** - ,1 'Irr,. .J ~ ~--=-*.-- -----:--=--- -. l"'N T-85' i, J~'  ;~  ;~gu~:lt---. -, ' ' - ' * \1 *' ,-* ,.,_ Jr. ~ .' , v,~ ';, ". .J.. ~

~

'].:" .. ' i' ~ -

_ 1* ** . ,, ,  :::

T-83 s29 .e1 l * ,, ,._:z:_ ~ -.....  ; -'" -~ -""' * ~ . .._ \_ ~- ~ ,:., ', ~* '.:. ~.

  • I:::

~m *.

929.80

'ti zr.;.-r..~

Y,TF,.I;,,

~--

,' ~,*

-.i -***, ... :1 J r;- ~ '1;i

  • _ - f;>:, ***1

~ t)

  • '-** **  ;-l'-
  • T-79

....__ 930 .07

,: I J

~-

'. J. .._

t->1 "

0

, .,_\.

1

'* ~

""~ y

  • , (**
.. ;a ,

~

\ ,.-,,,

\"4..I,.

i,, *,r1;,

.I , .J "C

X g E f::

r, .\__ ~  :::

i'k.

r,. J. '-:.,"£. _ ~'i*.. r~rl;'

E

,r '_1 .

  • L - , .
i, ,.,

1

~ ., ~

- . ~

~

~!~-,;~ -~ .~ ~ ./ '// ,.._"t;;.i_ '" ~~Cf

] T-68 ,

a

- _, ., '"" . J T-7? 930 .25

!1., "i T-81 ' 930.29

x
:~ *~~~

0 C:

I isl N

M 930.29 T-78 GE-WA-01 T-69 930 .35

~ '

  • 1

._ ,.- - ~ *

,;P J-.

~ T-54

~

~

~

~:,~

~

1/2*.

// ..

II'

~

942.47

'"':r * *. * ~*-

, '")'* *. ,1'*i~ * ,*

~

~g isl N

Ji~ * -- *-

iii 930 .39

'"i M "C

C:

Ill T-72 C/l T-75 930 .40 vii 930 .08 Ill T-76

~ ~ 930.52 .......... r.

C: .l_T-66

.2l i T-67 930 .61

- 930~.53 -63 0.50

.f' T-70R C.

T-74 930.72 T-65 !"t, ------

Ill 930 .6 5

.,u 930 .80

~

C/l u

QJ E

0

~

.2l 0

Cl.

0 N

Cl u::

<O aN 1i0 1335A 1324 "C

u

~

~ ~

u:: Figure 2- 1 01 u

WESTERN UPLAND CD ui AND ALLUVIAL AREAS CD l::

2016 POTENTIOM ETRIC SURFACE MAP

~ 2016 GROUNDW ATER MODEL UPDATE

~ CIMARRON SITE, OKLAHOMA 0

"'I .

~

_gu 0 Z ~

1339 1325 ~ BURNS iii~~ CDW-7Alc 'cow-7

'-'-MSDONNELL. environmental J1:,['l,~ ; 11,*  : :;: 1;**:Jf 1'fl

"'z C. <I'.

C\l[l_

:::; Legend

'a;O

=(.)

ll c., CDW-6~ DW-6 MONITORING WELL IN TRANSITION ZONE v,z 0-0JC:::

c.9W CDW-4A ..., CDW~ MONITORING WELL IN ALLUVIUM CDW-3

~~ 'f MONITORING WELL IN SANDSTONE A irozCD (cow-3A

.; w MONITORING WELL IN SANDSTONE B

~~~

CDW-2~

  • 1326

~z::: -l MONITORING WELL IN SANDSTONE C

~6

'E 0

~;~f-4 - - -~ / --~ 1319 947.62B-1

~ DW-2

~ 2016_GW_Flow_Arrows

=u

~::::; 131 ~ B-3 ,-* ~

1

~_: CDW-1A \ TRANSITION ZONE BOUNDARY

.: c6 UC/JO W7~ ~ 6 ~

. 1374 TERRACE DEPOSITS (ALLUVIUM) GW i::lz g cow-:"i a:::O::::: 1375

  • CONTOUR w=> 1329 1319 B-2 UCO s~

Zo

~

1328 948.71 SANDSTONE B GW CONTOUR WN 1n@ Groundwater elevation data collected on

.u~~I c., ;;;

August 8, 2016 .

Elevations are in feet above mean sea level .

1330 N 0~ 0 150 300 600

.c Cl.

.;o Cl.U Service Layer-Credits: Source: Esri , DigitalGlobe , GeoEye, Earthstar Geographies , CNES/Airbus DS , USDA, USGS, IGN, and l_~e ~IS User.,Community AeroGRID, Source: £SRI and Burns & McDonnell Engineering COORDINATES : (NAO 83) STATE PLANE OKL A HOMA NORTH FEE?

DATE . AERIAL PHOTO - 2010 I MA P PRODUCED - 72/20/2016 T"""'I'

-Feet 2091200 2091400 2091600 2091800 2092000 2092200 2092400 2092600 2092800 2093000 2093200 2093400 2093600 2093800 2094000 2094200  ;::;

2,095,250 2,095 ,500 2,095 ,750 2,096 ,000 0

0 0 0

~-

LO

~

1367 92 7.64 0

N 0

"'N

~-

"'~"

02W38 927.70 02W21 02W24 02W19, 02W14 02W11 TMW-23 927.41 927.83 927.82 927,761 927.74 928.51 02W23 927.89 02W17 927.86 02W06 02W07 927.87 927.87

~<.>...,

927.85 ,.9

-W12 927 ,73 0

0 0

' /.S 0 0

~

0 c-:i

~

02W05 TMW-13 02W22 927.88 927.90 927.89 02W33 927.96 02W15

. 927.91

1 E

~

~"

I

,Q a.

! 933.91 ----~----

932.18 02W30 -TMW-17 I

g 1316R 02W29 02W_1 4.99, 935 Figure 2-2 l'l 0 0 933 ,38 02W39 BURIAL AREA #1 Cl. "'

~\2l N~ 9-" 0 2016 POTENTIOMETRIC SURFACE MAP "'r---

935 .29 u.

<O 1315R 9,?,':f r- 937.06 935 -37, -

02W26 935.88 2016 GROUNDWATER MODEL UPDATE ~

~ 934.62 9,:i_:,,7 ~ TMW-01 -t- '-.__,. CIMARRON SITE, OKLAHOMA TMW-21 ~ 942 72 '-.. 02W4_1

~ 937.22 .l. ~~.LC\ ___. -A:'\. --......, 937 .T 9j _!.J6

~

j u:

o' u

T 0 2W40 939.37

+ ~ TMW~25 02W20 937

~ BURNS

'-.'-.M!:DONNELL env1ru11ment2l

, r-~ 11 11 111  : .fl'

~

iii 948.51 --+-~22~* 937_12 Legend t'i -.X 02W47 , TMW-201 @381' I.,,

0

-s-' , 940 .39

~TMW-02\

DRY ~

~~;>,.,

\

~

Monitoring Well in Alluvium Monitoring Well in Transition Zone

~~

  • 940:77+ 02W52 + Monitoring Well in Sandstone B

~l~-

02W51 -+\ \ 940.25

.:r-9~0 +

a. <:

roa. Monitoring Well in Sandstone C

~~

  • . =U 952 .18 u, '£. 4- Transition Zone Boundary

~(!) ~ (.J1 02W50 Terrace Deposits (Alluvium) GW Contours

~~

"a:

l'.IW 940.91 Sandstone B GW Contours j~

DC>

gz rowo ....., Groundwater Flow Direction

~:J~_ 0 0

-~~~

~zM Groundwater elevation data collected on

"'<'i QO ~

co

~~ August 8, 2016 .

=oc!i Elevations are in feet above mean sea level.

'.:1~

l;:a:

w :::J

  • Data from GE-BA1-01 not used in contouring um Zo WN GW = Groundwater

)ii@ 1314 ..L

~j:

si~ 944:451 0 30 60 120 AN

~~

Service Layer Credits: Source: Esri, Dig,talGlobe, GeoEye, Earthstar Geographies , CNES/Airbus DS, USDA. USGS ,

o Cl.U AeroGRID, IGN , and the GIS User Community Feet t-------------- .-------------- --1 COORDINATES
  • DATE *

(NAD83) STATE PLAN E OKLAHOMA NORTH FEET AERIAL P HOTO* 2D 1D I MAP PRODUCED 12/20/2D16 2,095 ,250 2,095,500 2,095 ,750 2,096 ,000

20876002087800208800 02088200208840020886 00208880020890002089 20020894002089600208 98002090000209020020 90400209060020908002 09100020912002091400 2091600209 18002092000209220020 92400209260020928002 09300020932002093400 20936002093800209400 02094200209440020946 00209480020950002095 20020954002095600209 58002096000209620020 96400209660020968002 09700020972002097400 0

0 N

l/)

N C")

0 0

FIGURE 3-1 0

l/)

N C")

MODEL DOMAIN AND MODEL 0

0 BOUNDARY CONDITIONS 00

'Sf" N

C")

EXPANDED WESTERN ALLUVIAL AREA 0

0 lD MODEL. CIMARRON SITE, OKLAHOMA

'Sf" N

C")

~

D D

'Sf"

'Sf" ~ BURNS

~ '-'-M£DONNELL. environmental D

n ,1 *'.t,* ** 1*1;..--q, ., ;,

D N

'Sf"

~

D "O

X D

D

'Sf" Legend

~ N C")

r--

x D

+

D 00

(")

N TREATMENT TRAIN 1 PUMPING WELL OR TRENCH

~rn C")

D D

"O <.D

(")

C: N

i (")

co 0

0 TREATMENT TRAIN 2 PUMPING WELL OR TRENCH D

GE-WA'A-05

+

ai 'Sf"

(")

"O N 0 (")

'i
0 0

PROPOSED INJECTION WELL "O N C: (")

rn N

(")

C:

co D 0

- PROPOSED GROUNDWATER EXTRACTION TRENCH E D 0 (")

GE-WAA-14 N

0 (") GE-WAA-15 ai "O

0

'i

c,i 0

0 0

00 N

N

(")

D 0

<.D

  • Ill PROPOSED INJECTION TRENCH MODFLOW GENERAL HEAD BOUNDARY CELLS

(/) N N

~ (")

i D ii:

Cl 0 V

N N

Ill MODFLOW RIVER CELLS 0

a.

(")

0 Q) 0 a: N U) N GE-WAA-04 MODFLOW NO FLOW CELLS

~

S2 D 0

'°a N

D N

N

(")

GE- - MODFLOW CONSTANT HEAD BOUNDARY CELLS D

0 0

00

~  ;:::;

(")

Cl

-~

ai D

0

<.D "O

0

(")

2 D

<( D V

~ -  ;:::;

-u (")

~~ D D

g >-- N oZ (")

~~ D D

/l~

-o D

-gu (")

u5 C!) D u~

wa:

0 00 D

N ow C")

<DW 0

~z o_ D

<.D NC!) D N

Oz (")

Uw D 2...J D OJ ...J V

¥ 0

~z lw N C")

~z D cno 000 N

0 U-01 D

i:::: (.) N C")

a:  ::;'i:

0

~~ 0 0

5u, 0 N

zZ (")

wa:

-=:i 0 0

!!l OJ 00 0)

~~

uo N

D

~@

0 lD 0) 0 250 500 1,000

9 I-  ;;;

"8::r:

EC!l

9 ir

.ca.

rnO a.u D

D V

0)

Souree : i=sri , DigitalGlooe, <Geo l::¥e, lfa rthsta 0mmunity cs , tl"J l::S/Airous DS , lUSDA, Feet Source: ESRI and Burns & McDonnell Engineering.

cooROINATEs, DATE ,

A (NAD 83) STATE PLANE OKLAHOMA NORTH FEET AERIAL PHOTO- 1010/MAPPRODUCED - 1/16/2017 20876002087800208800 02088200208840020886 00208880020890002089 20020894002089600208 98002090000209020020 90400209060020908002 09100020912002091400 20916002091800209200 02092200209240020926 00209280020930002093 20020934002093600209 38002094000209420020 94400209460020948002 09500020952002095400 20956002095800209600 02096200209640020966 00209680020970002097 2002097400

~~~~nft'.;;::;Mr;ii~F~§~i='::::~--7*--.*.**_-_-___ _-_*-_-.-,_-_--_~7 ---=--*-----~*--7--:--7 -----*-----~*------.-------*_-_--~*-*-_-_ __~--*_--~-~*-_-_-_ __--:---*_--~--*-_-_-._____

-_.-_-_-_.-_-_-__r_-_.-_-.-_**_-_-_ _ _ _-_.-_-~*-*-_-_-_ _ _ _-_.-_-~**_-_--_ _ _7~

~

FIGURE 3-2 ~

MODEL DOMAIN AND MODEL BOUNDA RY CONDITIONS BURIAL AREA #1 0

LO GROUND WATER MODEL r---_

(")

N

(")

0 0

LO

+ MONITORIN G WELL 0

(') PROPOSED EXTRACTIO N WELL 0 LO N

(") (')

PROPOSED INJECTION WELL N

(")

0 PROPOSED EXTRACTIO N TRENCH SUMP PROPOSED GROUNDW ATER EXTRACTIO N TRENCH 0

LO N_

(")

N

(")

- PROPOSED TREATED WATER INJECTION TRENCH MODFLOW GENERAL HEAD BOUNDARY CELLS 0

LO N_

(")

N

(")

MODFLOW RIVER CELLS MODFLOW NO FLOW CELLS 0 FORMER BA 1 WASTE DISPOSAL TRENCH 0

o_ 0

(") 0 N

o_

(") (")

N

(")

0 LO I'-_ 0 Ln N r---_

N

(") N N

(")

(.)

~

z

~

l: 0 0 0 O LO_ 0 0

c, N LO z N a: (") N N

w C"')

w z

az +

w

-I

-I w GE-BA 1-01 = Extraction Well z GETR-BA 1-01 = Extraction Trench Z 0 0 LO Cl N_ GWI-BA1-01 = Injection Well or Trench 0 u N LO

li N N_

oil (") N Cf) N z C')

er::

i co I!)

0 C\I 0 75 150 300 N

A

© aa: o_a I- 0 Feet Source: ESRJ and Burns & McDonn ell Engineering.

>- ce: Esri, DigitalGlobe , GeoEye, Earthstar Geographie s, CNES/Airbu s DS, USDA, USGS, AEX, Getmapping a..

N N , Aerogrid, IGN, 0

0

(") GI ser Community DATE:

AD 83) STATE PLANE OKLAHOMA NORTH FEET AERIAL PHOTO. 2010 I MAP PRODUCED. 12/ 19/2016 2,094 ,250 2,094,500 2,094,750 2,095,000 2,095,250 2,095,500 2,095,750 2,096,000 2,096,250 2,096,500 2,096,750 2,097,000 2,097,250

2089400 2089600 2089800 2090000 2090200 2090400 2090600 2090800 2091000 2091200 2091400 2091600 2091800 2092000 2092200 2092400 2092600 2092800 2093000 2093200 2093400 2093600 2093800 2094000 2094200 2094400 2094600 2094800 2095000 2095200 2095400 2095600 2095800 2096000 2096200 2096400 2096600 2096800 2097000 2097200 D

D D

'SI" N

C'1 FIGURE 3-3 D

MODEL PREDICTED POTENTIOMETRIC D

CD C'1 SURFACE WITH CALIBRATION TARGET N

C'1 RESIDUALS D

D (0

EXPANDED WESTERN ALLUVIAL AREA MODEL C'1 N

C'1 CIMARRON SITE, OKLAHOMA D

D "SI" ~ BURNS ~ .........,...

C'1 T-

~ '-'-M~DONNELL, enwonmental 1 r~(lr -* :1ti\- r :._~,.,.. .

D T-97

3t--f
  • D "O

N C'1 N

Legend X C'1

-0~4 ,/

E

--,-*O r-..:

x D

D g

N C'1 T-B 9 -0.51 T-61

+ 2 MONITORING WELL WITH RESIDUAL ERROR (IN

+-0~18T-51 I

Q)

CJ T-53 0 _12 FEET)

T;:59 -O 49

+ +-0.32 D

~ D CD

5 -0.22+ *

-\

N Cf) ~

CJ

  • .::: T-96 I\ T-60 930 POTENTIOMETRIC SURFACE CONTOUR (IN FEET Q)

E E

0 D

D (0

N N

C'1 J 1342 0.12 T-82 1.9

--1-016 T-87

-0.17 T- ABOVE SEA LEVEL) 2 "O

0 a..

Q)

D D

'SI" N

T-86 J_-0.08

--1-0.2 ~ MODFLOW GENERAL HEAD BOUDARY CELLS t5 N T-85

'o

~

C'1

-,---0.01 T-84 +- 0 a.. D D

N MODFLOW RIVER CELLS ai N "O

0 N

C'1 -7 T-72 1390

~

1'i 0.08 . 0.24 D

D - MODFLOW NO FLOW CELLS

~ 0 N

+

U) N Q) C'1

5 - MODFLOW CONSTANT HEAD BOUNDARY CELLS OJ 0 u: 0 CD 15

+

j C'1 C.

Q) a:: 0 in 0 (0

j S2 C'")

<D 0 0 0

N 'SI" 0

j C'")

E, OJ 0

.!: 0

('J ai  ;:::j "O C'")

0

i:

<( 0 0

~

0

-u.  ;:::j C'")

-~~

ai >-" 0 0

"8z co 0

~ ct N C'")

3 :i:

--o 0

-gu 0 (0

U) CJ 0 G~

wa::

N C'")

NOTES ow

<:OW

,-z 0

0

'SI" This figure illustrates:

o_ 0 NCJ N C'") 1) The model predicted potentiometric surface for the Oz Uw Sandstone Band Alluvial Units.

~ ...J 0 0

co ...J N

2) The model predicted residual for each monitoring

,-z lw 0 N

C'")

~z well. The residual is the measured water level mo a:, Cl i:::: CJ 0

0 0

(collected August 2016) minus the model computed a::~ 0 N water level.

C'")

~<><?5 sen zZ 0 0

3) Monitoring well size is proportional with the residual wa:: co 0, error in the model calibration.

-:::i

!!l co  ;;;

~~

uo 0

-N

~@

0

<D 0,

0 250 500 1,000 N

A 32 I-

"8:r: Feet ECJ 0 0

9~ '<l"

.ca..

0,

Sourc e
ESRI and Burns & McDonnell Engineerin g .

ciiO a..u Source : Esri , DigitalGlobe, - -...- arthstar Geographies, CNES/Airbus DS, USl9A, cooRDINATEs, DATE ,

Community (NAD 83) STATE PLANE OKLAHOMA NORTH FEET AERIAL PHOTO. 2010 I MAP PRODUCED. 12/2012016 2089400 2089600 2089800 2090000 2090200 2090400 2090600 2090800 2091000 2091200 2091400 2091600 2091800 2092000 2092200 2092400 2092600 2092800 2093000 2093200 2093400 2093600 2093800 2094000 2094200 2094400 2094600 2094800 2095000 2095200 2095400 2095600 2095800 2096000 2096200 2096400 2096600 2096800 2097000 2097200

FIGURE 3-4 0

U") MODEL PREDICTED POTENTIOM ETRIC r--_

C") SURFACE WITH CALIBRAIT ON TARGET N

C")

RESIDUALS

' 'I BURNS I M~DONNEL L.

Legend 0

0

~

C")

I ' Name 0 0

1 U?_

N C")

~ MONITORING WELL WITH RESIDUAL ERROR (IN C")

N

-~ FEET) C")

PROPOSED EXTRACTION WELL PROPOSED INJECTION WELL PROPOSED EXTRACTION TRENCH SUMP PROPOSED GROUNDWATER EXTRACTION 0 TRENCH U")

0 N__ U")

C") PROPOSED TREATED WATER INJECTION N__

N C") TRENCH C")

N C")

~2;62~

~ MODFLOW GENERAL HEAD BOUNDARY CELLS 2W34 '\_ I MODFLOW RIVER CELLS

.05 "-.....

02W24 ~ 02W19 MODFLOW NO FLOW CELLS

-0 08 -0 08 02W21 URANIUM > 180 PICOCURIES PER LITER (pCi/L) 048 ---+02w 0 I : I URANIUM> 30 MICROGRAMS PER LITER (ug/L) 0 1 9 q 1 0 C")

- BA 1 U > DCGL REMEDIATION AREA 0 o_

N 02 02W23 C")

C")

-0.18 GE-BA1 - BA1 U < DCGL REMEDIATION AREA N C")

02W22

-0.42 *'- - - - - - - - CJ FORMER BA1 WASTE DISPOSAL TRENCH BA1ESCARPM ENT

-

  • BA1 ESCARPMENT (INFERRED)

- TRANSITION ZONE BOUNDARY 0 POTENTIOMETRIC SURFACE CONTOUR (IN FEET

(.) ~ ABOVE MEAN SEA LEVEL) 0 U")

~ N r--_

~ N z C") N N

~ C")

~

0 u

C.9 z

ii:

w w

z (9

z w

..J 0

..J 0 w ~

0 0

Z N U?_

Z N g C") N N

(.) C")

~ GE-BA 1-01 = Extraction Well ca Cl) GETR-BA 1-01 = Extraction Trench z

a:: GWI-BA1-01 = Injection Well or Trench co N

l!)

0 N 0 75 150 300 I-I Cl ii:

a.

0 0

U?

N__

N N

C")

Service Layer Credits: Source: Esri, DigitalGlob IGP, swisstopo, and the GIS User Community Feet Source: ESRJ and Burns & McDonnell Engineering.

- - - - - - - - - - - - . - - - - - - - - - - - - - - r -N, COORDINATES : DA TE:

A 0 U")

N u (NAD 83) STATE PLANE OKLAHOMA NORTH FEET AERIAL PHOTO- 2010/MAP PRODUCED- 12/19/2016 C')

2,094,500 2,094,750 2,095,000 2,095,250 2,095,500 2,095,750 2,096,000 2,096,250 2,096,500 2,096,750

2089200 2089400 2089600 2089800 2090000 2090200 2090400 2090600 2090800 2091000 2091200 2091400 209 1600 2091800 2092000 2092200 2092400 2092600 2092800 2093000 2093200 2093400 2093600 2093800 2094000 2094200 2094400 2094600 2094800 2095000 2095200 2095400 2095600 2095800 2096000 2096200 2096400 2096600 2096800 209701 0

0 V

V N

C'?

Flow Rates Used in Model Simulatoin Train 1 Wells 0

0 FIGURE 4-1 N

V N

Well ID Flow Rate (gpm) FORWARD PARTICLE TRACKING SIMULATION C'?

0 GETR-WAA-01 15 EXPANDED WESTERN ALLUVIAL AREA MODEL 0

V N

0 GETR-WU-01 5 CIMARRON SITE, OKLAHOMA C'?

GE-WAA-01 20 0

0 IX)

C'?

GE-WAA-02 30 N

~

C'?

GE-WAA-03 20 ~ BURNS 0

0 GE-WAA-04 20 " -M~DONNELL. environmental

~ f' i lf !i ;s -t'l;:'CF.,

N C'?

GE-WAA-05 10 0

0 V

C'?

GE-WU-01 5 f;:j Train 2 Wells Legend 0

0 N

GE-WAA-06 13 C'?

"C E

N C'? GE-WAA-07 13

,-...:

  • INJECTION PARTICLES x

0 0

0 GE-WAA-08 13 Cl C

I C'?

N C'?

0 0

GE-WAA-09 GE-WAA-10 13 13

+ TREATMENT TRAIN 1 PUMPING WELL OR TRENCH u IX) rn N

.,:: N C'? GE-WAA-11 13 Q) TREATMENT TRAIN 2 PUMPING WELL OR TRENCH

] 0 0

GE-WAA-12 13 ro (0 Q.

"C N

N C'?

GE-WAA- 13 13 MOD PATH PARTICLE TRACK WITH ARROW SHOWING ro GE-WAA-14

~ 0 0

10 FLOW DIRECTION 0 V LL N

N N

C'?

GE-WAA-15 10 ci 0

e PROPOSED INJECTION WELL rJ) 0 Q) N N

i N C'?

.2' -

LL Injection Rates Used in Model Simulation PROPOSED GROUNDWATER EXTRACTION TRENCH 0

0 0 ~

a.

Q) 0 N

N Injection Trench/Wells a:: C'? - PROPOSED INJECTION TRENCH en Trench/Well ID Injection Rate (gpm) 9 0 0

GWI-WU-01 co" IX)

j 10 - MODFLOW GENERAL HEAD BOUNDARY CELLS 0 C'?

N GWI-WU-02 10

> 0

£ 0 0 (0

j GWI-UP1-01 30 - MODFLOW RIVER CELLS C'?

Cl

.!: GWI-UP2-01 22.5 ijj 0 "C

0 0

V GWI-UP2-02 5 - MOD FLOW NO FLOW CELLS 2

~ GWI-UP2-03

<l'. 5

~- 0 0 GWI-UP2-04 7.5 - MODFLOW CONSTANT HEAD BOUNDARY CELLS

-- C.)

-~~

N

j GWI-UP2-01 oi >=" C'? gpm = Gallons per Minute "8z

~~

\

0 0

0

{l2  ;::::j
  • -o

-g C.) C'?

ci5 (.') 0 NOTES C.)_ z 0 wa:: N IX) 0 This figure illustrates:

Cl W C'?

<O w 1) The model predicted particle tracking for the wells

.,....z a_ 0 N(.')

Cl Z 0

(0 that send water to Treatment Trains 1 and 2. The 0

Uw N C'? simulaiton inlcudes injection through trenches and 2....J aJ ....J

.,....z IW 0 wells in the Sandstone A and B upland areas.

0 R.z

0) 0 V

0 2) Pumping and injection rates used in the simulation f;:j co Cl F== (.J are summarized on the figure.

0::2

~oil 0

0 N

3) The groundwater model used was calibrated to 0

5 ti) N C'? August 2016 groundwater measurements for the zZ

--.l!l wO::

aJ 0

0 0

Sandstone 8 and Alluvial monitoring wells.

~~ N 0

uo

_.. N CC)

g t-0 0 0 250 500 1,000 N

A IX)

"8 I 0)

E (.') Feet

..c-

-- a::

.c Q.

0 0 Source: ESRI and Burns & McDonnell Engineering.

(0 "iiiO

--.v---~

0) a.. C.)  ;;; Souree : E:sri , DigitalGloBe , Geo Eye, ~arth """"-= ""= S, l!JS,DA, COORDINATES; DATE; (Comm unit¥ (NAD 83) STATE PLANE OKLAHOMA NORTH FEET AERIAL PHOTO . 2010 / MAP PRODUCED* 1/1612017 2089200 2089400 2089600 2089800 2090000 2090200 2090400 2090600 2090800 2091000 2091200 2091400 2091600 2091800 2092000 2092200 2092400 2092600 2092800 2093000 2093200 2093400 2093600 2093800 2094000 2094200 2094400 2094600 2094800 2095000 2095200 2095400 2095600 2095800 2096000 2096200 2096400 2096600 2096800 209701

FIGURE 4-2 0 in Flow Rates Used in Model Simulation FORWARD PARTICLE TRACKING r---._

('t")

Well Rate (gpm) SIMULATION N

('t")

GE-BA1-02 12 BURIAL AREA #1 GE-BA1-03 12 GROUNDWATE R MODEL GE-BA1-04 8 BURNS GE-BA1-05 8 M£DONNELL.

GE-BA1-06 0 0 GE-BA1-07 0 Legend 0 0 LC)

M GE-BA1-08 0 0 in C'\I M GE-BA1-09 10

  • FORWARD PARTICLES M N

C')

GE-BA1-10 10 MONITORING WELL Pumpin Trench Rate ( pm)

PROPOSED EXTRACTION WELL GETR-BA1-01A 15 GETR-BA1-018 15 PROPOSED INJECTION WELL GETR-BA1-02 10 PROPOSED EXTRACTION TRENCH SUMP Injection Trench Rate (gpm) PARTICLE TRACK WITH ARROW SHOWING 0

L!) GWI-BA1-01 10 FLOW DIRECTION 0 N_ in M GWI-BA1-02 5 N_

N M

PROPOSED GROUNDWATER EXTRACTION M N

TRENCH M PROPOSED TREATED WATER INJECTION TRENCH

- MODFLOW GENERAL HEAD BOUNDARY CELLS MODFLOW RIVER CELLS 0

0 o_ MODFLOW NO FLOW CELLS 0 0

('t") o_

N

('t") URANIUM > 180 PICOCURIES PER LITER M C'\I M

(pCi/L)

URANIUM > 30 MICROGRAMS PER LITER (ug/L)

BA1 U > DCGL REMEDIATION AREA 0 BA1 U < DCGL REMEDIATION AREA

~

z 0 FORMER BA1 WASTE DISPOSAL TRENCH cf.~ in r---._

0 in 0 N BA1 ESCARPMENT I"-,

(..) ~ N Cl N z BA1 ESCARPMENT (INFERRED) M ii:

w w

z - TRANSITION ZONE BOUNDARY CJ z

w

....J

....J w

GE-BA 1-01 = Extraction Well z GETR-BA1-01 = Extraction Trench z

0 GWI-BA 1-01 = Injection Well or Trench u

~ 0 olj 0 0

(/) ~ 0 Z N in_

0:: N

i C') N al C'\I

('t")

LC) 0 N 0 75 150 300 N

+

A (Q) 1- Feet

t:

Cl Source: ESRJ and Burns & McDonnell Engineering.

ii: Layer Credits: Source: Esri, DigitalGlobe, GeC,Eye Earthstar Geographies, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, a.

0 isstopo, and the GIS User Community COORDINATES : DATE:

(..) AD 83) STATE PLANE OKLAHOMA NORTH FEET AERIAL PHOTO - 2010 I MAP PRODUCED. 1/1612017 2,094,500 2,094,750 2,095,000 2,095,250 2,095,500 2,095,750 2,096,000 2,096,250 2,096,500 2,096,750

APPENDIX A GROUNDWATER FLOW MODEL REPORT (ENSR, 2006)

Prepared for:

Cimarron Corporation (Tronox)

Oklahoma City, Oklahoma Groundwater Flow Modeling Report ENSR Corporation October 2006 Document No.: 04020-044 ENSR AECOM

Prepared for:

Cimarron Corporation (Tronox)

Oklahoma Groundwater Flow Modeling Report Maya Desai and Ken Heim

~c..,D..,~

Pred By 1~&

Michael Meenan and James Cao Reviewed By ENSR Corporation October 2006 Document No.: 04020-044-327 ENSR AECOM

ENSR Contents

1.0 INTRODUCTION

........................................................................................................................................ 1-1 1.1 Overview ......... .... ..... ... .. ....................................................... ............................................................ 1-1 1.2 Background and Objectives .............. .. .. .... ....... .......................... .... ... ..... ... ....................... .. ..... ........ 1-1 2.0 HYDROGEOLOGIC FRAMEWORK ......................................................................................................... 2-1 2.1 Site Setting ........................................................ .............................................................................. 2-1 2.2 Precipitation .......................... .................................................................... ..... .................................. 2-1 2.3 General Geology ....... ...... ...... ........ .................................. ........................... .. ............................... .... 2-1 2.4 Site-Specific Geology ...................................................................................................................... 2-2 2.4.1 BA #1 Area ......... ..... .... .... ..................................... ............................................ ....... .. ........ . 2-2 2.4.2 Western Alluvial Area ........................................................................................................ 2-2 2.5 Hydrogeology ............................ .. ....................... ............................................................................. 2-3 2.6 Hydrologic Implications .................................... ............................................................................... 2-3

2. 7 Conceptual Model of Site Groundwater Flow ... ... .. ......................................................................... 2-4
2. 7.1 The Cimarron River .................................... .. ............... ............ .. ........................................ 2-4 2.7.2 BA #1 Area ................................. ..................... ................. .. .. .... ... .. ..................................... 2-4
2. 7.3 Western Alluvial Area ..................... ..................... ........................................................... ... 2-5 3.0 MODELING APPROACH .......................................................................................................................... 3-1 3.1 Groundwater Model Domain ................... .................. ... ... .. .. .... ........................................................ 3-1 3.1.1 BA#1 Area ....................................................... ......... ... ... ......... .. ........................................ 3-2 3.1.2 WA Area ......................................................................................... .......... ... ..... .. ................ 3-2 3.2 Hydrogeologic Physical Properties ... ........... ... ............. .. ............ .... .. ............................................... 3-3 3.3 Boundary Conditions ........ .. .. ................... ... .... .. .. ... .... ............. ... .... ........... ... ...... ..... ....... ... ........ ... .... 3-4 3.3.1 Recharge ............................................................................................................................ 3-4 3.3.2 Surface Water/Groundwater Interactions ......................................................................... 3-4 3.3.3 Upgradient General Head Boundary ................................................................................ 3-5 3.3.4 Underlying General Head Boundary ..... .. ... ....................................................................... 3-5 3.4 Summary of Modeling Approach ...... .. ......................................................... .... ... ............................ 3-5 4.0 MODEL CALIBRATION ............................................................................................................................ 4-1 4.1 Calibration Approach ..... ................ .. ................. .... ........................................................................... 4-1 4.1.1 Measured and Predicted Water Levels .... ..... ................................... ................................. 4-1 4.1.2 Volumetric Flow-Through Rate .......... ........... .... .. ........................... ... ..................... ........... 4-1 4.1.3 Plume Migration ................................................................................................................. 4-2 4.2 Calibration Parameters ........... ........ ............................................................................... ................. 4-2 Report No. 04020-044 October 2006 Groundwater Modeling Report

ENSR Contents, continued 4.3 Calibration Results ............................... ... ................. ... ................... ..... .... .. ...... .. ......... .................. ... 4-3 4.3.1 BA #1 .. .... .. ... .. ............ ...... ........... ..................................................................... .. ................ . 4-3 4.3.2 WA area ...... ........................................................................... ........ ........... ........... ........ ...... 4-4 4.3.3 Discussion .................................................................................................. ....... ................. 4-5 4.3.4 Summary of Calibration Results ........ ....................... ... .............. .......... .... ............... .. .... .... . 4-5 4.4 Sensitivity Analysis ... ............ .... .................. .... ......... .......................... ... .. ..... ... ........... ............ .. .. ...... 4-6 4.5 Uncertainties and Assumptions ............ .......... ........... ...... ......... .. ....... .. ... ... .. .... ... ...... ...... .. ......... ..... 4-7 5.0

SUMMARY

AND CONCLUSIONS ........................................................................................................... 5-1

6.0 REFERENCES

........................................................................................................................................... 6-1 Report No. 04020-044 ii October 2006 Groundwater Modeling Report

ENSR List of Tables Table 1 - Summary of Slug and Aquifer Test Results Table 2 - Summary of Groundwater Elevation Data used for Calibration Table 3 - BA #1 Summary of Model Inputs Table 4 - WA Area Summary of Model Inputs List of Figures Figure 1 - Site Location Map Figure 2 - Geology Along the Cimarron River From Freedom to Guthrie, Oklahoma Figure 3 - BA #1 - Geological Cross-Section Figure 4 -Western Upland and Alluvial Areas- Geological Cross-Section Figure 5 - BA#1 Model Domain Figure 6 - WA Area Model Domain Figure 7 - BA #1 Boreholes and Cross-sections Figure 8 - BA #1 Solids Developed from Borehole data Figure 9 - BA #1 3D grid incorporating geologic information Figure 10 - WA Area Boreholes and Cross-sections Figure 11 - WA Area Solids Developed from Borehole data Figure 12 - WA Area 3D grid incorporating geologic information Figure 13 - BA #1 Calibration Results Figure 14 - WA Calibration Results Report No. 04020-044 iii October 2006 Groundwater Modeling Report

ENSR

1.0 INTRODUCTION

1.1 Overview In order to depict and predict groundwater flow and to evaluate groundwater remediation alternatives, two groundwater flow models were developed for the Cimarron Site. These two models address two of the three areas on site that require remediation of Uranium (U) in the groundwater. The two models included Burial Area #1 (BA #1) and the Western Alluvial (WA) area.

Calibration was evaluated by comparing measured groundwater elevations, flow path data, and water budgets, with simulated elevations, paths, and budgets. Both flow models achieved adequate calibration to the observed groundwater elevation data, to observed flow path trajectories, and to the estimated water budgets.

Discrepancies between observations and predictions are considered reasonable. The overall water table configuration for each model was consistent with expectations based on observations of U concentrations.

Overall hydrogeological concepts as presented in the Conceptual Site Model (CSM), Rev 01 (ENSR, 2006) were captured by the numerical models.

The resulting models are useful tools to evaluate groundwater flow characteristics (velocities, flux rates, etc.)

and to evaluate different remediation scenarios including, but not limited to, understanding the permanence of the proposed remedial technique and to design the injection of reagents.

1.2 Background and Objectives Cimarron Corporation's site near Crescent, Oklahoma is a former nuclear fuel manufacturing facility. Since stopping operations, the site has been undergoing decommissioning under the oversight of the Nuclear Regulatory Commission (NRC) and the Oklahoma Department of Environmental Quality (ODEQ). As a result of the facility processes there are several areas at the Cimarron Site that have residual concentrations of Uranium (U) in the groundwater. Cimarron Corporation is currently considering remedial actions in Burial Area

  1. 1, the Western Alluvial Area, and the Western Uplands area. To support the design of these remedial systems, numerical groundwater flow models were developed for two of these areas. These models, based largely on data and concepts presented in the Conceptual Site Model (Rev 01, ENSR, 2006), serve as tools to evaluate remediation strategies.

The overall objective of this modeling effort was to provide tools by which remediation alternatives could be evaluated. This objective was achieved by setting up the numerical models to include geologic and hydrologic conditions as observed and documented in the CSM-Rev 01 (ENSR, 2006). The models were then calibrated to specific targets. This calibration process yielded two models that compared well to observations and therefore could provide a frame of reference with which to evaluate impacts from remediation alternatives.

These models were initially developed to support ENSR's remediation via pump and treat. While Cimarron was considering remediation via pump and treat, they were also considering bioremediation. In this latter process, via additives, the geochemical conditions in the aquifer would be converted to a reducing environment which would immobilize the U. This process has been conceptualized and proposed by Arcadis.

Data from these calibrated models and simulations using these numerical models can help to design either these or other remediation alternatives.

Note that even though there are detectable concentrations of U in the Western Upland area of the site, a numerical model was not constructed for that area. The conceptual site model for the WU area is presented in the CSM Rev 01 (ENSR, 2006). This conceptual site model forms the basis for ARCADIS' evaluation and selection of remedial design for this area. Given the extent of the U concentrations, complex numerical modeling for this area may not be necessary based on the remedial approach.

Report No. 04020-044 1-1 October 2006 Groundwater Modeling Report

ENSR 2.0 HYDROGEOLOGIC FRAMEWORK Much of the following has been extracted and paraphrased from the CSM-Rev 01 Report (ENSR, 2006). This section largely focuses on the parts of the CSM that were directly used in the modeling effort.

2.1 Site Setting The Cimarron Site lies within the Osage Plains of the Central Lowlands section of the Great Plains physiographic province, just south of the Cimarron River (Figure 1). The topography in the Cimarron area consists of low, rolling hills with incised drainages and floodplains along major rivers. Most of the drainages are ephemeral and receive water from storms or locally from groundwater base flow. The major drainage included in the models was the Cimarron River, which borders the site on the north. This river drains 4, 186 square miles of Central Oklahoma from Freedom to Guthrie, Oklahoma (Adams and Bergman, 1995). The Cimarron River is a mature river with a well-defined channel and floodplain. The stream bed is generally flat and sandy and the river is bordered by terrace deposits and floodplain gravels and sands (Adams and Bergman, 1995). In the area of the Cimarron Site, the ancestral Cimarron River has carved an escarpment into the Garber-Wellington Formation. Floodplain alluvial sediments currently separate most of the river channel from the escarpment. Surface elevations in the Cimarron area range from 930 feet above mean sea level (amsl) along the Cimarron River to 1,010 feet amsl at the former plant site. Between the river and the escarpment, the ground surface is flat relative to the variable topography of the escarpment and leading up to the uplands. Vegetation in the area consists of native grasses and various stands of trees along and near drainages. Soil thickness in the project area ranges from about one to eight feet.

2.2 Precipitation Adams and Bergman (1995) summarized the precipitation for the Cimarron River Basin from Freedom to Guthrie, Oklahoma. Their study showed that precipitation ranges from an average of 24 in/yr near Freedom, Oklahoma, in the northwest part of the Cimarron River floodplain in Oklahoma, to 32-42 in/yr at Guthrie, Oklahoma. Wet weather years occurred between 1950 and 1991, 1973-1975, 1985-1987, and 1990-1991.

The wettest months of the year are May through September, while the winter months are generally the dry months. The period from 1973 through 1975 had a total measured rainfall that was 23 inches above normal (Carr and Marcher, 1977). Precipitation data collected by the National Oceanic and Atmospheric Administration (NOAA) for Guthrie County, Oklahoma, from 1971 to 2000 indicates that the annual average precipitation is 36.05 inches.

2.3 General Geology The regional geology of the Cimarron area and the site-wide stratigraphic correlations for the project area can be combined into a general geological model for the Cimarron Site (Figure 2). The site consists of Permian-age sandstones and mudstones of the Garber-Wellington Formation of central Oklahoma overlain by soil in the upland areas and Quaternary alluvial sediments in the floodplains and valleys of incised streams.

  • The Garber sandstones dip gently to the west and are overlain to the west of the Cimarron Site by the Hennessey Group. The Wellington Formation shales are found beneath the Garber sandstones at a depth of approximately 200 feet below ground surface in the project area. The Garber Formation at the project site is a fluvial deltaic sedimentary sequence consisting of channel sandstones and overbank mudstones. The channel sandstones are generally fine-grained, exhibit cross-stratification, and locally have conglomeratic zones of up to a few feet thick. The sandstones are weakly cemented with calcite, iron oxides, and hydroxides. The silt content of the sandstones is variable and clays within the fine fraction are generally kaolinite or montmorillonite. The mudstones are clay-rich and exhibit desiccation cracks and oxidation typical of overbank deposits. Some of the mudstones are continuous enough at the Cimarron Site to allow for separation of the sandstones into three main units, designated (from top to bottom) as Sandstones A, 8, and C. Correlation of these three sandstone units is based primarily on elevation and the presence of a thick mudstone unit at the Report No. 04020-044 2-1 October 2006 Groundwater Modeling Report

ENSR base of Sandstones A and B that can be correlated between borings. Within each sandstone unit, there are frequent mudstone layers that are discontinuous and not correlative across the project area.

The Cimarron Site is located on part of an upland or topographic high between Cottonwood Creek and the Cimarron River. The project site is dissected by shallow, incised drainages that drain northward toward the Cimarron River. Groundwater base flow and surface water runoff during storms have been ponded in two reservoirs (Reservoirs #2 and #3) on the project site. The Cimarron River is a mature river that has incised the Garber Formation, forming escarpments that expose the upper part of the Garber sandstones. Within the Cimarron Site, the Cimarron River has developed a floodplain of unconsolidated sands, silts, and clays that separate the Garber sandstones exposed in an escarpment from the main river channel. Surface drainages within the project site flow toward the Cimarron River. Geological features of each modeled area of the Cimarron Site are as follows:

  • BA #1 Area - The upland is underlain by a sequence of sandstone and mudstone units, namely, from top to bottom, Mudstone A, Sandstone B, Mudstone B, and Sandstone C. The alluvium can be divided into a transitional zone located within the erosional drainage area and an alluvial zone located north of the escarpment line. The transitional zone consists predominantly of clay and silt and overlies Sandstone B or Mudstone B. A paleochannel appears to exist in the transitional zone, which may control the flow of groundwater in the vicinity of the upland in this area. The alluvium consists of mainly sand and overlies Sandstone C and Mudstone B. Additional descriptions of the geology of this area are included in the CSM-Rev 01 Report (ENSR, 2006).
  • Western Alluvial Area - Alluvial sediments in this area consist of predominantly sand with minor amounts of clay and silt. Sandstone B and Mudstone B exist beneath the alluvial sediments near the escarpment and Sandstone C underlies the alluvial sediments farther out in the floodplain. Additional descriptions of the geology of this area are included in the CSM-Rev 01 (ENSR, 2006) .

2.4 Site-Specific Geology 2.4.1 BA #1 Area Geologic logs from seventy-five boreholes were used to describe the subsurface geology in the immediate vicinity of the Uranium (U) plume at the BA #1 area. The lithologic logs collected from borehole cuttings described the subsurface geology as a sequence of interbedded layers of near surface unconsolidated alluvial material and deeper consolidated sandstones and mudstones. The logs identified twenty-seven unique material types, which included unconsolidated materials of varying degrees of sand, silt, and clay, anthropogenically disturbed surficial deposits, and sedimentary rock. In an effort to simplify the conceptualization of the subsurface geology these twenty-seven different material types were collapsed into nine distinct material types representing strata with significantly different hydrogeologic characteristics. The four unconsolidated materials include, fill, sand, silt, and clay, and the underlying consolidated units include Sandstone A, Sandstone B, and Sandstone C, interbedded with two distinct mudstone layers (Figure 3). The simplified lithologic units describe, from the surface downward, fill material in the uplands and widely scattered silt in the upland and alluvial areas. In the alluvial areas this is underlain by a thick sandstone unit with a relatively thick bed of clay within the unit. The upland areas and beneath the alluvium consist of interbedded sandstone and mudstone. Because of varied topography and elevation the exposure of materials at the site varies widely. In the upland areas most of the exposed material is either sandstone or mudstone while in the alluvium most of the exposed material is either sand or to a lesser extent silt and clay. All data in the lithologic logs was used in the development of the model 2.4.2 Western Alluvial Area The subsurface geology at the WA area was depicted by geologic logs from twenty boreholes near the escarpment. In contrast to the geology of the BA#1 area, the subsurface of the WA area is a relatively flat, "pancake" geology where Sandstone C, the lowest sandstone indicated in the BA #1 area, is overlain by a continuous unit of unconsolidated alluvial sand, which is overlain by a intermittent unit of unconsolidated clay Report No. 04020-044 2-2 October 2006 Groundwater Modeling Report

ENSR (Figure 4). A simplification of the information from the lithologic logs was not necessary for the WA and the inconsistent distribution of clay around the site was largely due to topography and the erosion of the clay in the low lying areas. All data in the lithologic logs was used in the development of the model 2.5 Hydrogeology Groundwater flow through above-described regional geologic units is governed by recharge areas and discharge areas.

Regionally, recharge is precipitation (rain, snow, etc) that infiltrates past the root zone to the water table. As discussed above, the average annual precipitation rate is approximately 30 in/yr. Recharge to the alluvium and terrace deposits along the Cimarron River was estimated to be 8 percent of precipitation based on baseflow calculations and the assumptions of steady-state equilibrium in the alluvium and terrace sands (Adams and Bergman, 1995). Rainfall recharge to groundwater is therefore estimated to be approximately 2.4 4

in/yr (5.5 x 10- ft/day).

Discharge of groundwater occurs at low points in the watershed and generally coincides with streams and lakes. At this site the Cimarron River is a local and regional discharge boundary. Average annual baseflow in the Cimarron River should equal average annual recharge indicating that the recharge and discharge rates are balanced.

Recharge to the groundwater system typically occurs at topographic highs. The application of this water to the groundwater system results in downward gradients in the recharge areas; that is, there is a component of flow downward in addition to horizontal. Conversely, discharge from the groundwater system occurs at the topographic low points in any given watershed, for instance at a stream, river, or lake. Because of this, groundwater gradients tend to be upward in these areas; that is, there is component of flow upward in addition to horizontal. The flow path of any given unit of groundwater depends on where in the watershed it originates as recharge and how far it has to flow to discharge.

2.6 Hydrologic Implications The site-specific geology suggests several hydrologic implications including:

  • The alluvial material was largely deposited by the historical meandering of the Cimarron River and the deposition of overbank deposits that result from intermittent floods on the river. This inconsistent and repeating depositional cycle resulted in a series of inter-bedded unconsolidated material types that are collectively referred to as alluvium, which on a small scale can exhibit variable hydrogeologic characteristics but on a larger scale can be considered collectively.
  • Groundwater discharged from the Garber-Wellington formation largely discharges through the alluvial deposits on its way to its final destination, the Cimarron River.
  • Since both the WA and the BA #1 areas are within the Cimarron River alluvial valley, both areas receive groundwater from both upgradient discharge of groundwater to the alluvial deposits and from subsurface discharge of water from the deeper aquifer to the alluvium and river system. In general, flow from the southern upgradient sandstones to the alluvium is characterized as horizontal flow and flow from the sandstone underlying the alluvium is characterized as having a component of vertical (upward) flow.
  • The sandstone and siltstone/mudstones of the Garber-Wellington formation are relatively impermeable when compared to the unconsolidated alluvial sands adjacent to the river. This suggests that the water table gradient in the sandstone would be relatively steep when compared to the alluvial sand. This would further suggest that water could be more easily withdrawn from the alluvial sand than from the consolidated sediments occurring both beneath, and upgradient of the alluvial material.

Report No. 04020-044 2-3 October 2006 Groundwater Modeling Report

ENSR

  • In addition, within the bedrock, the sandstone units have higher permeability relative to the mudstones. Therefore, more groundwater flow is expected to take place horizontally within these water bearing units, with less flow between the units.

The hydrogeologic characteristics of the Cimarron River alluvial system are typical of a relatively permeable aquifer system receiving groundwater from an adjacent, less permeable bedrock aquifer and transferring the groundwater to the discharge zone, in this case the Cimarron River.

2.7 Conceptual Model of Site Groundwater Flow The Conceptual Site Model (CSM) of the Cimarron River flow system was developed prior to the development of groundwater models for the WA area and the BA #1 area. The CSM was incorporated into the groundwater models to ensure that the models used existing information and an accepted interpretation of the site-wide geology. The conceptual models for the WA area and the BA #1 area were developed separately and as such are discussed separately. However, it is recognized that the conceptual models for the two areas must be consistent.

2.7.1 The Cimarron River The Cimarron River is a significant hydrogeologic boundary for the entire Cimarron Site. The headwaters of this river are in New Mexico and from there it flows through Colorado, Kansas, and Oklahoma. In the vicinity of the Site (Freedom to Guthrie, OK) the Cimarron River is a gaining river. That is, it is a discharge zone for groundwater. Groundwater flow into the river is controlled by the difference in elevation of groundwater and in the river and by the conductivity of the river bottom sediments. The elevation of the river changes seasonally, but this can be represented as an average annual elevation for this steady-state modeling effort. Changes in the elevation of the river may result in short-term changes in the groundwater flow directions and gradients in the nearby alluvial materials. However, over the long-term, an average elevation is appropriate to reflect the average groundwater flow system. Cimarron River streamflows and associated water level elevations in the immediate vicinity of the Western Alluvial area and BA#1 model domains has not been historically measured.

The variability in river water levels at the site were estimated using long term flow records (1973 through 2003) from the USGS stream gages at Dover (30.0 miles upstream to the west) and Guthrie (10.3 miles downstream to the east). Daily averaged water level elevations at each of the two sites were averaged and the average water level elevation for the area of the model domains was determined through linear interpolation to be th 925.0 feet. A further statistical evaluation indicated that the 5 percentile of water level elevations at the site th was 924.1 feet and the 95 percentile of water level elevations was 927.7 feet; therefore, 90% of the time the Cimarron River water level at the site varies within a range of 3.60 feet.

2. 7.2 BA #1 Area Groundwater in the vicinity of the BA #1 Area originates as precipitation that infiltrates into the shallow groundwater in recharge zones, both near the BA #1 area and in areas upgradient of the BA #1 area. The amount of water flowing from the sandstones into the modeled area and into the alluvial material is controlled by the changes in groundwater elevation and hydraulic conductivities between the two units.

Local to the BA #1 area, infiltrated rainwater recharges the shallow groundwater in the area of the former disposal trenches and then flows into Sandstone B. The reservoir also contributes water to the groundwater system. This groundwater then flows across an escarpment that is an interface for the Sandstone B water-bearing unit and the Cimarron River floodplain alluvium, and finally into and through the floodplain alluvium to the Cimarron River. Flow in Sandstone B is mostly northward west of the transitional zone and northeastward along the interface with the transitional zone. Flow is driven by a relatively steep hydraulic gradient (0.10 foot/foot) at the interface between Sandstone B and the floodplain alluvium. Once groundwater enters the transition zone of the floodplain alluvium, the hydraulic gradient decreases to around 0.023 foot/foot and flow is refracted to a more northwesterly direction. The decrease in hydraulic gradient is due in part to the much higher overall hydraulic conductivity in the floodplain alluvium compared to Sandstone B (10-3 to 10-2 cm/sin Report No. 04020-044 2-4 October 2006 Groundwater Modeling Report

ENSR alluvium versus 10-5 to 10-4 emfs in Sandstone B). The refraction to the northwest is primarily due to a paleochannel in the floodplain alluvial sediments. The direction of this paleochannel is to the northwest near the buried escarpment and then is redirected to the north as it extends farther out into the floodplain. Once groundwater passes through the transitional zone, it enters an area where the hydraulic gradient is relatively flat. Data indicates that the gradient in the sandy alluvium is approximately 0.0007 ft/ft. Figure 3-4 in the CSM-Rev 01 Report (ENSR, 2006) presents a potentiometric surface map of Sandstone Band the alluvium for the BA #1 area based on groundwater level measurements during August/September 2004. Seasonal data between 2003 and 2005 indicate that although groundwater levels may change seasonally, the hydraulic gradients and groundwater flow directions do not change significantly over time (ENSR, 2006).

2.7.3 Western Alluvial Area Groundwater in the vicinity of the WA area originates as precipitation that infiltrates into the shallow groundwater in recharge zones both near the WA area and in areas upgradient of the WA area. Most of the groundwater in the WA area comes from the discharge of groundwater from Sandstones B and C to the alluvial materials. The amount of water flowing from the sandstones to the alluvial material is controlled by the difference in groundwater elevation and hydraulic conductivities between the two geologic units. Groundwater flow in the WA area is generally northward toward the Cimarron River; flow is driven by a relatively flat hydraulic gradient of 0.002 foot/foot. Figure 3-6 in CSM-Rev 01 Report (ENSR, 2006) presents a potentiometric surface map of the alluvium for the WA area based on groundwater level measurements during August/September 2004. As with the BA#1 Area, although groundwater levels may change seasonally, there is little change over time in hydraulic gradient and groundwater flow directions.

Report No. 04020-044 2-5 October 2006 Groundwater Modeling Report

ENSR 3.0 MODELING APPROACH Groundwater flow at the two Cimarron sites (BA #1 and WA areas) was simulated using the three-dimensional MODFLOW model (McDonald and Harbaugh, 1988). The MODFLOW model uses a block-centered finite-difference method to simulate groundwater flow in three dimensions. The MODFLOW model was selected because of its wide acceptance by the technical community, because of its robustness, and because several Windows based applications support the model, including the GMS 6.0 modeling package, which was used for this project. The GMS 6.0 software package is a visualization package that facilitates easy manipulation of the MODFLOW input and output files. In addition to using the MODFLOW groundwater model, the MODPATH particle tracking program was used to simulate the transport of groundwater particles within the model domain as a direct result of a flow field predicted by MODFLOW.

3.1 Groundwater Model Domain The domains of the BA #1 area and WA groundwater models were set up to include the specific areas of interest and all important boundary conditions.

For the BA #1 area, the specific area of interest was located northwest of the Reservoir #2 from the source area in the uplands, downgradient through the transition zone, and into the alluvial sands (Figure 5). The downgradient boundary was the Cimarron River and the upgradient boundary was along an east-west line coincident with the Reservoir #2 dam. Groundwater flow is primarily northward, so boundaries parallel to groundwater flow were set up at locations upstream and downstream along the Cimarron River far enough away from the high U concentrations and parallel to flow lines to not influence the interior of the model domain during pumping simulations. The lower boundary (i.e., bottom) of the BA #1 model domain was fixed at elevation 900 feet, well below the lower extent of the alluvial aquifer.

In the case of the WA area, the specific area of interest was located just downgradient of the escarpment along a north-trending line of high U concentrations (Figure 6). The downgradient boundary was the Cimarron River and the upgradient boundary was set at the escarpment. Groundwater flow is primarily northward so boundaries parallel to groundwater flow were set up at locations upstream and downstream along the Cimarron River far enough away from the high U concentrations to not influence the interior of the model domain during pumping simulations. The lower boundary (i.e., bottom) of the WA area model domain was fixed at 870 feet, well below the lower extent of the alluvial aquifer.

The model domain for the BA #1 area was set up to include the area from the upgradient reservoir to the south, to the Cimarron River to the north, and to distances east and west adequate enough to have a negligible effect on the interior of the model domain. The model was developed with grid cells that are 10 feet square in the X-Y plane and with 12 layers extending from the land surface down to a depth of elevation 900 feet, resulting in approximately 270,000 grid cells within the model domain.

The model domain for the WA area was set up to include the area from the escarpment to the south to the Cimarron River to the north and east and west to distances adequate enough to have a negligible effect on the interior of the model domain. The model was developed with grid cells that are 10 feet square in the X-Y plane and with 2 layers extending from the land surface down to a depth of elevation 870 feet, resulting in 97,830 grid cells within the model domain. The high density of grid cells within each model domain was selected for two reasons including: 1) to provide for a finely discretized model within the area of the U plume for testing the effects of groundwater pumping, and 2) to provide for adequate representation of the subsurface geology into discrete geologic material types, particularly for the BA#1 area.

Report No. 04020-044 3-1 October 2006 Groundwater Modeling Report

ENSR 3.1.1 BA #1 Area The model layers for the BA #1 area were developed directly from the lithologic information from the seventy-two boreholes that were available for the site. A simplification of the original borehole data, which had originally described 27 unique lithologic types, was imported directly into the GMS 6.0 modeling platform, as the basis for the groundwater model. The simplified geology included the following geologic units/materials:

1) fill, 2) silt, 3) an upper sand unit, 4) clay, 5) a lower sand unit, 6) an upper sandstone unit (Sandstone A), 7) an upper mudstone (A), 8) a middle sandstone unit (Sandstone B), 9) a lower mudstone (B), and 10) a lower sandstone unit (Sandstone C). Each of the boreholes was reviewed in light of the surrounding boreholes to ensure that the inter-relationships between boreholes were realistic and representative of the CSM-Rev 01 (ENSR, 2006) developed for the site. Following the importation and adjustment of the borehole information, each layer in each of the seventy-two boreholes was assigned a Horizon ID to indicate the layer's position in the depositional sequence at the Site. The GMS 6.0 modeling platform was then used to "connect" the boreholes to form cross-sections based on the Horizon IDs assigned to each of the boreholes. Since a cross-section was developed for every adjacent borehole, this resulted in a total of one hundred sixty-five cross-sections; each of which was reviewed to ensure the sensibility of the interpretations. In cases where the cross-section did not make geologic sense, the cross-section was manually modified (Figure 7).

Once the cross-sections were developed and checked for accuracy, the GMS 6.0 program was used to develop three-dimensional solids of each material type within the intended model X-Y model domain. Each of the 3-D solids was represented by upper and lower TIN (triangularly integrated network) surfaces and was created using the previously developed cross-sectional data. Each of the solids types corresponded to the nine geologic units indicated by the lithologic information for the boreholes (Figure 8).

The model boundaries were identified and incorporated into the GMS 6.0 platform, including the location of the river boundary, the general head boundary, and the recharge boundary (discussed in the next section).

One of the last steps in the development of the BA #1 area groundwater model was to develop a generic, twelve layer 3D grid that encompassed the model domain on a 10 ft by 1Oft horizontal spacing. The next step in the development of the model was to assign hydrogeologic properties to each of the material types and boundaries and then transition all of the 3-D solids information to the 3-D grid that is used by the MODFLOW and MODPATH models (Figure 9). The final step was to make modifications to the distribution of material types (i.e., hydraulic conductivities) to adjust for the discrepancies between the mathematically interpreted version of the distribution of soil types and the interpretation of soil types based on the CSM (ENSR, 2006).

3.1.2 WA Area The model layers for the WA area were developed directly from the lithologic information from the twenty boreholes that were available for the site. The borehole data was imported directly into the GMS 6.0 modeling platform as the basis for the groundwater model. Each of the boreholes was reviewed in light of the surrounding boreholes to ensure that the inter-relationships between boreholes were realistic and representative of the CSM, Rev.1 (ENSR, 2006) developed for the site. Following the importation and adjustment of the borehole information, each layer in each of the twenty boreholes was assigned a Horizon ID to indicate the layer's position in the depositional sequence at the site. The GMS 6.0 modeling platform was then used to "connect" the boreholes to form cross-sections based on the Horizon IDs assigned to each of the boreholes. Since a cross-section was developed for every adjacent borehole, this resulted in a total of forty-one cross-sections; each of which was reviewed to ensure the sensibility of the interpretations. In cases where the cross-section did not make geologic sense, the cross-section was manually modified (Figure 10).

Once the cross-sections were developed and checked for accuracy, the GMS 6.0 program was used to develop three-dimensional solids of each material type within the intended model X-Y model domain. Each of the 3-D solids was represented by upper and lower TIN (triangularly integrated network) surfaces and was created using the previously developed cross-sectional data. Each of the solids types corresponded to the three geologic units indicated by the lithologic information for the boreholes (Figure 11). It should be noted that the geologic materials in the WA area consisted only of sandy alluvium and the underlying bedrock (Sandstone C), so this process was much simpler than for the BA#1 area.

Report No. 04020-044 3-2 October 2006 Groundwater Modeling Report