ML20214N774

Forwards Siting Section Comments on Riverton Remedial Action Plan.Comments Transmitted W/O Author Changes Due to Tight Time Constraints

ML20214N774
Person / Time
Issue date:	05/20/1987
From:	Starmer R NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
To:	Fliegel M NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
References
REF-WM-60 NUDOCS 8706030062
Download: ML20214N774 (29)

Text

. .

NAY 2 01987 MEM0 FLIEGEL MEMORANDUM FOR: Michael F11egel Operations Branch Division of low-Level Waste Management and Decommissioning FROM: R. John Starmer, Section Leader Technical Branch Division of Low-Level Waste Management and Decommissioning

SUBJECT:

COMMENTS ON THE RIVERTON REMEDIAL ACTION PLAN This memorandum transmits the Siting Section (LLTB) comments on the Riverton Remedial Action Plan to the Uranium Recovery Section (LLOB). I have reviewed the comments and have identified needed changes. Due to tight time constraints, the coments are being forwarded without incorporating my changes.

Kristin Westbrook of my staff and your P.M., George Pangburn, have discussed my coments with me and will be working with the individual technical reviewers to ensure that my comments are addressed.

Ori61nal Signed By R. John Starmer Section Leader Technical Branch Division of low-Level Waste Management and Decommissioning

Enclosure:

Coments l

'/,'l I'mrj I !3 W.'! Pr: ~f . . h_ _.__.

D ,w lh _ _ . . _ _ _

l l' A W. . . . . . .

LEM _ . _ _ _ _ _ .

P::' rih W.w

' ~

[jy6og 070s;!o iMua't 4 M t . 3 ' h -

WM-60 PDR

h)rU-(oO MAY 2 0 3187 MEM0 FLIEGEL 2

OFFICIAL CONCURRENCE AND DISTRIBUTION RECORD FOR: M. Fliegel FROM: R. J. Starmer

[

SUBJECT:

COMMENTS ON THE RIVERTON REMEDIAL ACTION PLAN DATE: 5/18/87 l

DISTRIBUTION

' LL'WM/SF l NMSS RF LLTB r/f KWestbrook RJStarmer JJSurmeier l

CONCURRENCES ORGANIZATION /CONCUREE INITIALS DATE CONCURRED LLTB/KWestbrook/jl LLTB/RJStarmer IV A

/ld 05/q /87 05/go/87 l

1 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton, WY Date: May 14, 1987 Document: Draft EA Comentor: NRC/ geology Comment: G1 Page: general Based upon the level of data provided on detailed lithology and stratigraphy of the Wind River Formation beneath the site, staff are unable to complete an analysis of hydrogeology of the confined and unconfined aquifers. Data i supporting an EA assertion that no communication occurs between the aquifers is sparse and ambiguous. For example:

1) tritium concentrations are elevated in confined sandstones (p. C-109)

2) the text blames sampling and analytical errors without correcting or accounting for the errors (p. C-109) ,

3) data derived from pump tests in the unconfined aquifer are acknowledged to be unusable (p. C-145)

4) some evidence suggests tailin unconfined aquifer (p. C-159)gs are a source of pollution in the More detailed information on lithology and stratigraphy of the Wind River j Formation should be collected before a final analysis of its relation to site hydrogeology is completed. These data could be derived from further drilling and coring, inspection of outcrops in the field, laboratory grain-size and petrographic analyses, and published geological literature.

l l

l SECTION 2 l

Response: Page By: Date:

Plans for Implementation:

m .. .

~_.s

0

.h i

2 SECTION 3 Confirmation of Implementation:  !

. Checked by: . Date:

, Approved by: , Date: ,,

i I

J l

3 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton, WY Date: May 14, 1987 Document: Draft EA Commentor: NRC/ geology Comment: G2 Page: 42 Pleistocene glacial ages and the Quaternary Period extend further in time than 1 million~ years ago.

SECTION 2 Response: Page By: Date: _ _ _

Plans for Implementation: .

i SECTION 3 Confirmation of Implementation:

Checked by: , Date: l Approved by: , Date:

4 UKTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton, WY Date: May 14, 1987-Document: Draft EA Commentor: NRC/ geology Comment: G3 Page: 43 & C-95 The drawing of the stratigraphic column beneath the site is missing the interval 48-100 feet deep.

.p SECTION 2 ,

Response: Page By: Date:

,~

Plans for Implementation: .

5 l

l 4

SECTION 3 Confirmation of Implementation:

Checked by: , Date:

Approved by: ,Date:

2

.i i

s

, , _. , _ , - . - . , , ..c _ -. _ _ , . . _ _ . _ _ , , . - ,. . ,,y

5 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton, WY Date: May 14, 1987 Document: Draft EA Commentor: NRC/ geology Comment: G4 Page: 48 & C-9 The text claims that the largest paleochannel of Wind and Little Wind Rivers is 2,100 feet southwest of the tailings site. Based upon staff's inspection of aerial photos, it is not clear that the referenced paleochannel was larger than any other through geologic time. -The staff consider this channel was equally significant as any other channel which passed, and may pass again, directly through the site.

SECTION 2 Response: Page By: Date:

Plans for Implementation:

l l

1 I

SECTION 3 I

Confirmation of Implementation: l l

Checked by: , Date: 1 Approved by: ,Date:

I l

l

6 UMTRA DOCUMENT REVIEW FORM SECTION 1 4

Site: Riverton, WY Date: May 14, 1987 Document: Draft EA Commentor: NRC/ geology.

Comment: G5 Page: 49-50 & C-14 to C-16 The EA here includes a lengthy discussion of data and analyses regarding a 500-year floodplain. However, no rationale is provided to explain the

- relationship between this analysis and that of a more conservative analysis regarding probable maximum floods.

t SECTION 2 Response: Page By: Date:

Plans for Implementation:

T 1 i 1

9 j SECTION 3 Confirmation of Implementation:

Checked by: , Date:

l Approved by: ,Date.

l l

1 l i

7 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton, WY Date: May 14, 1987 Document: Draft EA Connentor: NRC/ geology Comment: G6 Page: C-58 Paragraph two states that groundwater is drawn from sandstones in the lower Wind River Formation. This is not accurate. The sandstones may represent lower attainable aquifers in the area, but shallow-bedrock .in this area consists of uppermost fine-grained facies formally considered the upper Wind River Formation. These references to the " lower Wind River Formation" should be revised.

SECTION 2 Response: Page By: Date:

Plans for Implementation:

SECTION 3 Confinnation of Implementation:

Checked by: , Da te:

Approved by: , Date:

I l

8 e

1

UMTRA' DOCUMENT REVIEW FORM i

~

SECTION 1 4 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 1 Page: _3_

The RAP states that the Processing Site Characterization Report (PSCR) and the Environmental Assessment (EA) describe the results of remedial . actions. Both of these documents are prepared in support of design of remedial actions and, therefore, cannot describe "results of remedial actions!' Section 1.4 should be revised.to correct this error.

f 4

SECTION 2 i

Response: Page By: Date:

l

Plans for Implementation:

a i

i .

SECTION 3 l Confirmation of Implementation:

Checked by: I , Date:

j Approved by: , Date:

I h

m.

9 l

l UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 2 Page: 7 Section 2.4 concludes by stating that DOE does not anticipate that any ,

substantive changes to the planned remedial actions will be required to comply j with the new groundwater protection standards to be promulgated by EPA in place of the guidance in Subpart C of 40 CFR Part 192. Selection of remedial actions that may be necessary to comply with new groundwater protection ,

standards, however, can only occur after the standards have been promulgated. {

Therefore, the lengthy description of the implementation guidance in Subpart C {

should be omitted from the text because it may no longer be relevant to DOE's. .{

selection of remedial actions for the Riverton site. This section should be i revised to indicate that remedial actions to protect water resources will be selected after EPA promulgates water protection standards in 40 CFR Part 192.

SECTION 2 Response: Page By: Dnte: _

Plans for Implementation:

t SECTION 3 Confirmation of Implementation:

Checked by: ,Date:

Approved by: ,Date:

10 UMTRA DOCUMENT REVIEW FORM i

SECTION 1 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber

Comment: 3 Page: 11 I

! The reference in the last sentence of Section 3.1 to the map showing the designated site and land ownership should be revised to Figure 3.3 rather than 3.2. The reference to the map showing the Riverton site in the first sentence of Section 3.2 should be revised to Figure 3.2 rather than 3.3. .

! SECTION 2 Response: Page By: Date:

i

! Plans for Implementation:

i SECTION 3 4

! Confirmation of Implementation:

Checked by: , Date:

Approved by: , Date:

)

_ . _ , _ _ - _ - _ . _ - . _ _ . . _ _ _ _ _ _ . _ . _ - _ . - . . _ _ _ . _ ~ _ _ _ , _

11 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton . Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 4 Page: 15-The RAP's description of subsurface features at the Riverton site incorrectly states that the sandy gravel beneath the site acts as a " perched water-table aquifer." This. statement is based on a 1983 unpublished Environmental Assessment by Ford, Bacon, and Davis. More recent evaluations of the Riverton l

site (e.g., the final Environmental Assessment (DOE, 1987)) have failed to ' il demonstrate the existence of shallow perched groundwater beneath the site.

The interconnection of the shallow groundwater to deeper aquifers is important to decisions about the need to restore or control the shallow contaminated aquifer. Therefore, the RAP should clearly state that the shallow alluvial ,

aquifer is h not perched)ydraulically or demonstrateconnected to deeper that the shallow hydrogeologic groundwater is perched units because (i.e., it isit ,

is separated from deeper aquifers by an unsaturated zone.  ;

SECTION 2 Response: Page By: Date:

1 Plans for Implenentation:

l SECTION 3 Confirmation of Implementation:

Checked by: , Date:

Approved by: . Date:

I

.pl

12 VMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 5 Page: 18 The RAP states that contaminated groundwater would require at least 20 years to migrate from the unconfined aquifer to the first confined sardstone and an additional 1800 years to migrate from this unit to the deeper sandstones below 200 feet depth. The RAP does not, however, summarize the calculations that support these estimates or cite a reference that provides the calculations.

The RAP should be revised to summarize the technical basis that supports these estir,iates or cite a document that describes the calculations in sufficient detail. The basis for the calculations should justify the parameter values selected for the calculations, as well as describe the assumptions and the conceptual model upon which the calculations are based.

SECTION 2 Response: Page By: Date:

Plans for Implementation:

SECTION 3 Confirmation of Implementation:

Checked by: ,Date:

Approved by: ,Date:

13 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 6 Page: 20 The RAP states that contaminated groundwater at the Riverton site does not pose appreciable health hazards based on comparisons of the contaminant concentrations with the EPA primary drinking water standards as described in the Environmental Assessment. These statements may be misleading because two of the most important contaminants at the Riverton site, uranium and molybdenum, are not included in EPA's primary drinking water standards.

Judgments on the need for remedial actions for groundwater contamination should be deferred until EPA promulgates final standards for groundwater protection at UMTRAP sites. The RAP should be revised to delete the conclusion that groundwater contamination at Riverton does not pose any appreciable hazards or to demonstrate the absence of such hazards.

SECTION 2 .

Response: Page By: Date:

Plans for Implementation:

SECTION 3 Confinnation of Implementation:

Checked by: , Date: l l

Approved by: ,Date:

i l

i 14.

j UMTRA DOCUMENT REVIEW FORM

SECTION 1 Site

Riverton , Date: April 1987 i

~

Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 7 Page: 21 The RAP states that after the Riverton processing site has been decontaminated, the site will be regraded, revegetated, and released for _

unrestricted use consistent with existing local land use controls. . Release of the site for unrestricted use, however, may be inconsistent with institutional l controls imposed at the site to preclude use of contaminated groundwater. The l RAP should be revised to indicate that potential release of the Riverton -

j processing site for unrestricted use will be contingent upon the imposition, 3

or lack thereof, of institutional controls for groundwater protection.-

1 SECTION 2

, Response: Page By: Date:

Plans for Implementation:

i

}

l

. l

, i

SECTION 3 i

Confirmation of Implementation: )

Checked by: ,Date:

Approved by: , Date:

4

- , . . _ , - ,, .. . - _ , , . . , . - . , - _ . , , , - _, _,, , -~ . - . = . . . . , . - - - . , -

2-15 :l r

UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton , Date: April 1987' Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 8 Pagas: 24 and 26 The RAP states that DOE will remove contaminated subgrade materials at the Riverton processing site. The RAP also states that relocation of the tailings to the Gas Hills site will eliminate the_ source of future groundwater contamination. Based on the definition of " contaminated," however, decontamination will not include removal of sediments beneath the site that ,

have been contaminated with non-radiological constituents unless they occur with radiological constituents above the concentration limits provided in 40 - -

CFR Part 192 (5 pCi/g and 15 pCi/g of Ra-226). Sediments contaminated with

non-radiological constituents may remain on-site after completion of the j decontamination process. The contaminated sediments may constitute a 1 long-term source of contaminants to shallow groundwater beneath the site. The RAP should be revised to demonstrate that the contaminated sediments remaining beneath the site will not significantly degrade shallow groundwater or to include measures to limit the impacts of such . residual contamination.

SECTION 2 Response: Page By: Date:

Plans for Implementation:

4 i

SECTION 3 i Confirmation of Implementation:

i Checked by: , Date:

! Approved by: ,Date:

e I

- . _ . . - , , ,y.. .-,,.,- --, ,.- _ , , -- -g , , - - , _ , , , _ . - _ , ,

, . y

16 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton .

Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 9 Page: 24 The RAP describes the process for selecting remedial measures to protect and/or restore groundwater. This description is based on regulatory guidance provided in Subpart C of 40 CFR Part 192, which is no longer valid for the UMTRA Project. Because the process for selecting remedial actions for groundwater protection may change as a result of changes in the standards, this section should be revised to indicate that DOE will select measures to comply with EPA's standards for groundwater protection after they have been promulgated.

SECTION 2 Response: Page By: Date:

Plans for Implementation:

SECTION 3 Confirmation of Implementation:

Checked by: , Date:

Approved by: ,Date:

17 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 10 Page: 26 The RAP states that natural restoration will reduce concentrations of contaminants in shallow contaminated groundwater to background levels within approximately 45 years and cites the Environmental Assessment as the basis for this estimate. The assessments in the EA, however, do not consider desorption and release of less mobile contaminants than the sulfate used in the solute  ;

transport model. The decreased mobility of contaminants such as molybdenum I compared with sulfate may be evident in comparisons of the extent and rate of-migration of their respective contaminant plumes in shallow groundwater

downgradient of the site. Therefore, the RAP should be revised to indicate that plumes of contaminated groundwater may persist long after the estimated 45-year period for natural restoration as indicated in the RAP and the EA.

4 SECTION 2 Response: Page By: Date:

Plans for Implementation:

l SECTION 3 Confirmation of Implementation:

, Date: l Checked by:

Approved by: , Date:

1 1

_ _ _, , _ __ -_ _ .l

18

, UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 11 Page: 26 The RAP states that DOE will construct a small evaporation pond with a liner to ensure groundwater protection. The RAP does not, however, provide the design characteristics of the pond or identify the types of assessments that '

3 will be performed to ensure groundwater protection. For example, the RAP does not indicate whether the pond will be lined with low-permeability clay or flexible synthetic material. The RAP should be revised to provide design '

characteristics and to demonstrate the adequacy of the design of the evaporation pond to protect groundwater against additional contamination.

SECTION 2 Response: Page By: Date:

Plans for Implementation:

SECTION 3 Confirmation of Implementation:

Checked by: * , Date:  !

Approved by: . Date:

1 i

I

4 19 4

UMTRA DOCUMENT REVIEW FORM l

l SECTION 1

] Site: Riverton . Date: April 1987 j Document: Remedial Action Plan /EA j Connentor: Michael Weber 1

4 Comment: 12 Page: 26 i The RAP does not indicate whether DOE will impose any institutional controls as interim measures to protect humans from contaminated groundwater prior to selection of final measures to comply with the EPA standards. The RAP should

1. be revised to demonstrate that such institutional controls are not necessary

! to protect the public or to describe the type of controls that will be implemented in the interim prior to DOE's selection of remedial measures for groundwater protection.

\

.i SECTION 2 Response: Page By: Date: '

i Plans for Implementation:

I L

1 SECTION 3 Confirmation of Implementation:

Checked by: ,Date:

Approved by: ,Date:

20 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton ~~, Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 13 Page: 26 TheEnvironmentalAssessment(pagesC-105,109,157,159,169,171,and175) for remedial actions at the Riverton site indicates that confined groundwater may have been contaminated by seepage of shallow contaminated groundwater 4 beneath the site. The RAP, however, does not discuss or identify this contamination. Since the confined groundwater system at Riverton is used more heavily than the shallow system, existing and potential future contamination of the deeper confined system may be more significant than existing

- contamination in the shallow system. Therefore, the RAP should be revised to -

describe the contamination of the confined groundwater system or demonstrate that such contamination does not and will not exist.

1 SECTION 2 Response: Page By: Date:

Plans for Implementation:

I 1 SECTION 3 Confirmation of Implementation:

i Checked by: , Date:

Approved by: . Date:

21 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton . Date: April 1987

' Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 14 Page: 27 The RAP states that requirements for possible restoration of contaminated groundwater at the Riverton site will be determined by EPA's new standards and State of Wyoming groundwater protection standards. The RAP should reference specific Wyoming standards that apply to groundwater restoration at UMTRAP sites. l l

l i

s 1

SECTION 2 i

l Response: Page By: Date:

Plans for Implementation:

I SECTION 3 Confirmation of Implementation:

Checked by: , Date:

Approved by: , Date:

22 4

UMTRA DOCUMENT REVIEW FORM SECTION 1 4

Site: Riverton . Date: April 1987 l' Document: Remedial Action Plan /EA Commentor: Michael Weber 1

Comment: 15_ Page: 28 The RAP states that dewatering of the tailings .uay be required prior to their 1 excavation and relocation to the Gas Hills site. The RAP does not, however, estimate pumping rates or locations that may be necessary to dewater the *-

tailings. The RAP does not discuss or justify the selection of specifications for the dewatering system. In addition, dewatering may represent an opportunity to begin restoration of the shallow contaminated aquifer beneath -

the site. Therefore, the RAP should be revised to provide specifications for-the dewatering system and to consider the utilization of the dewatering system to restore the shallow groundwater system. In addition, the RAP should indicate that the evaporation pond has been designed with adequate capacity to collect and evaporate contaminated water that may be extracted using the dewatering system. ,

i SECTION 2 Response: Page By: Date:

4 Plans for Implementation:

l 4

a i

I i

SECTION 3 Confirmation of Implementation:

Checked by: , Date:

Approved by: . Date:

I i

23 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 16 Page: 29 Section 4.4.8 should be revised to include a commitment from DOE to restore borrow areas prior to completion of remedial actions at the Riverton site.

4 SECTION 2 Response: Page By': Date:

Plans for Implementation:

SECTION 3 Confirmation of Implementation:

Checked by: . Date:

Approved by: , Date:

24 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton . Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 17 Page: 30 The cost estimate for ramedial actions does not include any estimates for decommissioning monitoring wells and for constructing a water treatment plant that may be required to treat contaminated water removed from the dewatering system. The RAP should be revised to include such estimates. The cost section should also indicate that costs for groundwater protection cannot be estimated until measures have been selected to comply with EPA's standards for groundwater protection.

SECTION 2 Response: Page By: Date:

Plans for Implementation:

SECTION 3 Confirmation of Implementation: l l

Checked by: . Date:

Approved by: ,Date:

m 4

25 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton . Date: April 1987 Document: Remedial Action Plan /EA Comentor: Michael Weber Coment: 18 Page: 35

" Natural" in " Natural Emission Standard for Asbestos" should be changed to "Nati onal . "

t SECTION 2 Response: Page By: Da te:

Plans for Implementation:

SECTION 3 Confirmation of Implementation:

Checked by: , Date:

Approved by: ,Date:

1 26 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton . Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber Comment: 19 Page: 37 The introduction to Section 6.2 is not written as a sentence. The text should be revised to correct this error.

SECTION 2 Response: Page By: Date:

I Plans for Implementation:

1 SECTION 3 Confirmation of Implementation:

Checked by: . Date:

Approved by: ,Date:

27 UMTRA DOCUMENT REVIEW FORM SECTION 1 Site: Riverton , Date: April 1987 Document: Remedial Action Plan /EA Commentor: Michael Weber l

Comment: 20 Page: 41

! The text should be revised to indicate that long-term monitoring, maintenance, and/or control may be necessary at the decommissioned Riverton processing site depending upon measures selected for groundwater protection.

I l

1 1

l I

SECTION 2 Response: Page By: Date:

J Plans for Implementation:

I 1

l SECTION 3 Confirmation of Implementation:

I l Checked by: , Date: >

l Approved by: , Date:  !

j

- .