ML20155B437

From kanterella
Jump to navigation Jump to search
Clarifies Typo in Site Rept, Final Technical Evaluation Rept for Proposed Remedial Action at Durango Tailings Site, Durango,Co
ML20155B437
Person / Time
Issue date: 07/28/1988
From: Grace S, Hawkins E
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
REF-WM-48 NUDOCS 8810060305
Download: ML20155B437 (3)


Text

o.

p2 M4 UNITED STATES 9

y

\\

NUCLEAR REGULATORY COMMISSION b*

e REGION IV URANIUM RECOV FIELD OFFICE

,o DENVER, COLORADO 80225 JA. 281988 URF0:SRG Oocket No. VM-48 HEMORANDUM FOR:

Docket File No. WM-48 FROM:

Scott R. Grace, Project Manager Licensing Branch 1 Uranium Recovery Field Office, Region IV

SUBJECT:

CLARIFICATION OF TYP0 GRAPHICAL ERROR IN THE NOVEMBER 16, 1987, DURANGO TECHNICAL EVALUATION REPORT BACKGROUND 4

The report entitled, "Final Technical Evalaution Report for the Proposed Remedial Action at the Durango Tallings Site, Ourango, Colorado," (TER) with accompanying transmittal memo dated November 16, 1987, contains a typographical error that has led to some confusion.

The staff believes that it is necessary to clarify any confusion that may have been created as a result of the typographical error.

DISCUS $10N Section 3.4.3, Ground-Water Impacts - Disposal Site of the TER, third paragraph, last sentence, contains a typographical error for the Darcian infiltration rate.

The TER has a value of 0.0022 cm/yr.

This value should be 0.315 cm/yr.

The text states:

For greater conservatism, a value of IE-8 cm/s and a unit gradient of one was used to calculate a Oarcian infiltration of 0.0022 cm/yr, for a total estimated infiltration and saturation time of greater

!{

6-foot thickness results in a value of 83,091 years.

This is significantly than 500 years.

Using 0.0022 cm/yr to calculate the time to infiltrate a different thei the "greater than 500 year" conclusion in the TER.

Using the i

correct result of the Darcian equation, 0.315 cm/yr gives an actual result of i

580 years.

SUMARY The typographical error is noted and clarified.

As noted in the TER, additional information on the potential for infiltration of the cover is required from 00E and the staff are deferring their final conclusions on ground Oro m

  • m 9g eeo7:e I

WM-48 PDC g

i

e.

2 JUL. 28 IW water at the Durango site until such time that DOE re-evaluates infiltration.

Staff review of additional information will be presented as a supplement to the TER..

d 9O Scott R. Grace, Project Manager Licensing Branch 1 Uranium Recovery Field Office Approved by:

A Eoward F. Flawkint, Chief Licensing Branch 1 Uranium Recovery Field Office, Region IV cc:

M. Fliegel, LLOB R. J. Starmer, LLTB-P. Lohaus, LLOB J. Surmeier, LLT8 s

a

.:.; o.4 e

WM-48/SRG/88/07/28/0 DISTRIBUTION Docket File WM-48

/ POR/DCS %

R. L. Bangart, RIV SGrace RCPD, CO LLO Branch, LLWM-URF0 r/f i

e3 j

w

g a u-y q

n, 1

m 6

l I

CONCURRENCE:

DATE:

EHawkins/URF0 */d c.s.

---/

9 W f 4

l SGrace/URF0 tRG 7~d-ff i

l l

\\\\1 0

f