ML20206R955
| ML20206R955 | |
| Person / Time | |
|---|---|
| Issue date: | 11/04/1998 |
| From: | Joseph Holonich NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| To: | Rael G ENERGY, DEPT. OF |
| References | |
| REF-WM-69 NUDOCS 9901270020 | |
| Download: ML20206R955 (4) | |
Text
{{#Wiki_filter:. _ _ Mr. G org3 R::1, Director November 4, 1998 U.S. D:ptrtm:nt of En:rgy { Albuqu::rque Op: rations Offica i ERD /UMTRA f. P.O. Box 5400 Albuquerque, NM 87185-5400
SUBJECT:
REVIEW OF PROJECT INTERFACE DOCUMENT NOs 14-S-19,14-S 21, AND l 14-S-22 FOR MAYBELL, COLORADO
Dear Mr. Rael:
By letters dated July 16, August 28, and October 14,1998, the U.S. Department of Energy (DOE) transmitted Class l Project Interface Document (PID) Nos.14-S-19,14-S-21, and 14-S-22, respectively, for the Maybell, Colorado, Uranium Mill Tailings Remedial Action site to the U.S. Nuclear Regulatory Commission (NRC) for review and approval. Based on its reviews, the NRC staff has concluded that PID Nos.14-S-19 and 14-S-21 are acceptable as proposed by I DOE. The NRC staff's review is documented in the enclosed Technical Evaluation Reports. J Regarding PID No.14-S-22, the staff determined that DOE needs to provide additional information on the minor changes proposed for the four gullies downstream of the disposal cell. l Specifically, DOE indicates on several PID drawings that minor changes may be made to any of these guliies at the discretion of its contractor. Such ambiguous statements make it virtually impossible for the NRC staff to judge the adequacy of these changes (e.g., DOE may consider that revising e gully depth by three feet to be a minor change, therefore not requiring additional NRC review ano approval-- whereas the NRC staff may consider such a change to be major). Accordingly, DOE should provide additional information on each of the changes made to the design or construction of the aforementioned gullies, including detailed descriptions of the l changes, analyses supporting the acceptability of the changes, and any revised construction drawings. If you have any questions concerning this subject, please contact Mr. Robert Carlson of my staff at (301) 415-8165. Sincerely, [Signedby] Joseph J. Holonich, Chief Uranium Recovery Branch }f Division of Waste Management 9901270020 981104 - Office of Nuclear Material Safety f and Safeguards 69 PDR
Enclosures:
As stated cc: W. Woodworth, DOE Alb. M-{] F. Bosiljevac, DOE Alb. M E. Artiglia, TAC Alb. .g 7 DISTRIBUTION (w/ enci): File Center PUBLIC NMSS r/l URB r/f l CCain, RIV CNWRA ACNW AGarcia TJohnson (w/o encI): MWebber MLayton DOCUMENT NAME: S:\\DWM\\ URB \\RDC\\MAYBELL\\19_21_22.PID OFC URB f URB oa Ui3d b NAME CAbr nich DATE // /2 /98 // ll/0h98 /[/h/98 OFFICIAL RECORD COPY
f$ UNITED STATES l j NUCLEAR REGULATORY COMMISSION t. WASHINGTON. D.C. 2055 5 0001
- /
November 4, 1998 Mr. George Rael, Director U.S. Department of Energy Albuquerque Operations Office ERD /UMTRA P.O. Box 5400 Albuquerque, NM 87185-5400
SUBJECT:
REVIEW OF PROJECT INTERFACE DOCUMENT NOs.14-S-19,14-S-21, AND j 14-S-22 FOR MAYBELL, COLORADO
Dear Mr. Rael:
) By letters dated July 16, August 28, and October 14,1998, the U.S. Department of Energy (DOE) transmitted Class l Project interface Document (PID) Nos.14-S-19,14-S-21, and 14-S-22, respectively, for tne Maybell, Colorado, Uranium Mill Tailings Remedial Action site to the U.S. Nuclear Regulator / Commission (NRC) for review and approval. Based on its reviews, the NRC staff has concluded that PID Nos.14-S-19 and 14-S-21 are acceptable as proposed by DOE. The NRC staff's review is documented in the enclosed Technical Evaluation Reports. Regarding PID No.14-S 22, the staff determined that DOE needs to provide additional information on the minor changes proposed for the four gullies downstream of the disposal cell. Specifically, DOE indicates on several PID drawings that minor changes may be made to any of these gullies at the discretion of its contractor. Such ambiguous statements make it virtually imoossible for the NRC staff to judge the adequacy of these changes (e.g., DOE may consider that revising a gully depth by three feet to be a minor change, therefore not requiring additional NRC review and approval-- whereas the NRC staff may consider such a change to be major). Accordingly, DOE should provide additional information on each of the changes made to the I design or construction of the aforementioned gullies, including detailed descriptions of the changes, analyses supporting the acceptability of the changes, and any revised construction drawings. If you have any questions concerning this subject, please contact Mr. Robert Carlson of my staff at (301) 415-8165. Sincerely, 0' (. ,, y*r{s<y' j "f 7 v Joseph J. Holonich, Chief Uranium Recovery Branch Division of Waste Management Office of Nuclear Material Safety l and Safeguards
Enclosures:
As stated cc: W.Woodworth, DOE Alb. l F. Bosiljevac, DOE Alb. E. Artiglia, TAC Alb. i 1.
l a TECHNICAL EVALUATION OF MAYBELL PID NO.14-S-19 DATE: October 22,1998 FACILITY: Maybell, Colorado PROJECT MANAGER: Robert Carlson TECHNICAL REVIEWER: Ted Johnson
SUMMARY
AND CONCLUSIONS: By letter dated July 16,1998, the U.S. Department of Energy (DOE) submitted Project Interface Document (PID) Number 14-S-19 to the U.S. Nuclear Regulatory Commission (NRC), indicating its intention to change the design and specifications for the riprap and filter to be placed on the disposal cell. DOE provided detailed calculations and analyses to support this request. Based on review of the information provided, the NRC staff concludes that the proposed changes are acceptable. DESCRIPTION OF DOE'S REQUEST: DOE performed sieve analyses to determine the gradations of the riprap and filters, as required by the specifications, and found that the rock did not meet those specifications. These analyses showed that the percentage of Type B rock passing the 3-inch sieve exceeded the maximum allowable percentage of 36 percent, and that the percentage of Type C rock passing the 5-inch sieve exceeded the maximum allowable percentage of 55 percent. Similar problems were also identified for the filter / bedding materials, which did not meet gradation specifications. DOE provided analyses to show that the rock and filter layers, although not meeting . specifk tions, are adequate to meet design requirements. TECHNICAL EVALUATION: The design average rock sizes (D s) for Type B and Type C rock were based on rock 30 produced from the Maybell gravel source. These rocks had a lower angle of repose because they were round and had lower specific gravities than the ay;ular rock actually produced from the Juniper Mountain Quarry source. DOE provided calculations to show that the D a rock sizes 3 actually required are less than the original design requirement and are less than actually placed. The NRC staff reviewed DOE's proposed specification change and concludes that the Do size and gradations proposed are acceptable. 3 DOE provided actual gradations of the filter layers to show that the filter layers would drain freely and would have adequate permeability. DOE provided revised gradation specifications to show that the filter layers would be well-graded and that smaller sizes were acceptable because the original specifications were conservative. NRC staff review of the information provided indicates that DOE's original specifications were more conservative than actually required, and e that the revised filter gradations wwe acceptable to provide adequate drainage. Therefore, the NRC staff recommends approval of the revised specifications. I
e s l TECHNICAL EVALUATION OF MAYBELL PID NO.14-S-21 DATE: October 22,1998 FACILITY: Maybell, Colorado PROJECT MANAGER: Robert Carlson TECHNICAL REVIEWER: Ted Johnson
SUMMARY
AND CONCLUSIONS: By letter dated August 28,1998, the U.S. Department of Energy (DOE) submitted Project interface Document (PID) Number 14-S-21 to the U.S. Nuclear Regulatory Commission (NRC), indicating its intention to change the design of the Rob Pit overburden pile and the design of the diversion berm near the pile. DOE provided detailed calculations and analyses to support this request. Based on review of the information provided, the NRC staff concludes that the proposed changes are acceptable. DESCRIPTION OF DOE'S REQUEST: Fill material from the Rob Pit overburden pile was extensively used during construction of the cover for the Maybell disposal cell. As a result, more material than expected was excavated, and the top of the pile is now about 45 feet lower than expected. Thus, the lengths of the side slopes of the overburden pile have been greatly reduced. DOE now proposes that smaller Type B rock be used, in lieu of Type C rock, on these shorter side slopes. In addition, the potential for sediment transport from the pilo has been greatly reduced, and DOE proposes that the sediment retention berm located between the pile and the diversion ditch be redesigned. DOE indicates that no riprap is needed for such a small berm and there is no need to provide an excavated opening to release flood flows stored behind the berm. TECHNICAL EVALUATION: DOE recalculated the required riprap size that would be needed on the shortened side slopes of the Rob Pit overburden pile. Using the Safety Factors Method, the required average rock size (Dw) was computed to be 1.8 inches. DOE proposes to use Type B riprap with a De ize s of 3.7 inches. Based on staff review of the revised slope lengths and the calculations provided in the submittal, the NRC staff concludes that the riprap design is acceptable. DOE also reevaluated the design of the berm to store flood runoff and prevent that runoff from entering the diversion channel. DOE provided calculations showing that the Probable Maximum Flood (PMF) would be discharged from the area behind the berm at an elevation that is one foot less than the actual height of the berm. These calculations also showed that the natural discharge opening was adequate and an artificial cut was not needed to produce additional flow area for the PMF. In addition, the low height (generally 4-8 feet) of the berm was evaluated, and it was determined that there would not be a need for riprap due to the very short slope lengths. Based on its review of the calculations and information provided by DOE, the NRC staff concludes that the berm design is acceptable. 1}}