ML021200681
| ML021200681 | |
| Person / Time | |
|---|---|
| Site: | Saxton File:GPU Nuclear icon.png |
| Issue date: | 05/01/2002 |
| From: | Alexander Adams NRC/NRR/DRIP/RORP |
| To: | Kuehn G GPU Nuclear |
| Adams A, NRC/NRR/DRIP/RORP, 415-1127 | |
| References | |
| -nr, TAC MA8076 | |
| Download: ML021200681 (8) | |
Text
May 1, 2002 Mr. G. A. Kuehn, Jr.
Vice President SNEC and Program Director SNEC Facility GPU Nuclear, Inc.
Route 441 South P.O. Box 480 Middletown, PA 17057-0480
SUBJECT:
SAXTON NUCLEAR EXPERIMENTAL FACILITY - DISCUSSION TOPICS FOR MAY 8, 2002, MEETING (TAC NO. MA8076)
Dear Mr. Kuehn:
We are continuing our review of your amendment request for Amended Facility License No.
DPR-4 for the Saxton Nuclear Experimental Corporation (SNEC) Facility which you submitted on February 2, 2000, as supplemented. As part of our review, we have arranged a meeting with you that is open to public observation on May 8, 2002, to discuss details of our review of your application related to pathways analysis. The details of the meeting were sent to you under separate cover. This is a follow up to our meeting of April 8, 2002.
To facilitate our discussions on May 8, 2002, please find enclosed comments and issues that were identified during our review of your License Termination Plan, response to requests for additional information and information given to us during the April 8, 2002, meeting. The enclosure is not a request for additional information and may not contain all technical issues identified by the staff. Following our meeting, we may issue a request for additional information based on the outcome of the meeting.
If you have any questions regarding this review, please contact me at (301) 415-1127.
Sincerely,
/RA/
Alexander Adams, Jr., Senior Project Manager Research and Test Reactors Section Operating Reactor Improvements Program Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation Docket No. 50-146
Enclosure:
As stated cc w/enclosure: Please see next page
Saxton Nuclear Docket No. 50-146 Experimental Corporation cc:
Mr. Michael P. Murphy Bureau of Radiation Protection Department of Environmental Protection 13th Floor, Rachel Carson State Office Building P.O. Box 8469 Harrisburg, PA 17105-8469 Mr. Jim Tydeman 1402 Wall Street Saxton, PA 16678 Mr. James H. Elder, Chairman Concerned Citizens for SNEC Safety Wall Street Ext.
Saxton, PA 16678 Mr. Ernest Fuller 1427 Kearney Hill Road Six Mile Run, PA 16679 Saxton Borough Council ATTN: Judy Burket 707 9th Street Saxton, PA 16678 Mr. David J. Thompson, Chair Bedford County Commissioners County Court House 203 South Juliana Street Bedford, PA 15522 Mrs. Alexa Cook, Chairman Huntingdon County Commissioners County Court House Huntingdon, PA 16652 Saxton Community Library P.O. Box 34 Saxton, PA 16678 Carbon Township Supervisors ATTN: Penny Brode, Secretary R. D. #1, Box 222-C Saxton, PA 16678 Hopewell Township - Huntingdon County Supervisors ATTN: Reba Fouse, Secretary RR 1 Box 95 James Creek, PA 16657-9512 Mr. D. Bud McIntyre, Chairman Broad Top Township Supervisors Broad Top Municipal Building Defiance, PA 16633 Mr. Don Weaver, Chairman Liberty Township Supervisors R. D. #1 Saxton, PA 16678 U.S. Army Corps of Engineers Baltimore District ATTN: S. Snarski/P. Juhle P.O. Box 1715 Baltimore, MD 21203 The Honorable Robert C. Jubelirer President Pro-Temp Senate of Pennsylvania 30th District State Capitol Harrisburg, PA 17120 Mr. James J. Byrne Three Mile Island Nuclear Generating Station P.O. Box 480 Middletown, PA 17057 Mr. Robert F. Saunders First Energy Corp.
76 South Main Street Akron, OH 44308 Ms. Mary E. OReilly First Energy Legal Department 76 South Main Street Akron, OH 44308
Mr. Manuel Delgado 2799 Battlefield Road Fishers Hill, VA 22626 Mr. Eric Blocher 216 Logan Avenue Wyomissing, PA 19610 Mr. David Sokolsky 1000 King Salmon Avenue Eureka, CA 95503 Mr. Gene Baker 501 16th Street Saxton, PA 16678 Mr. Dick Spargo 1004 Main Street Saxton, PA 16678 Mr. Mark E. Warner AmerGen Energy Co., LLC P.O. Box 480 Middletown, PA 17057 James Fockler, Chairman Saxton Citizens Task Force 1505 Liberty Street Saxton, PA 16678 Dr. Rodger W. Granlund Saxton Independent Inspector Radiation Science and Engineering Center The Pennsylvania State University Breazeale Nuclear Reactor University Park, PA 16802-2301 Mr. Gareth McGrath Altoona Mirror 301 Cayuga Avenue Altoona, PA 16603 Dr. William Vernetson Director of Nuclear Facilities Department of Nuclear Engineering Sciences University of Florida 202 Nuclear Sciences Center Gainesville, FL 32611 Mrs. Bunny Barker Box 143, RR 1 James Creek, PA 16657 Mr. William Kanda First Energy Operating Corp.
10 Center Road Perry, OH 44081
May 1, 2002 Mr. G. A. Kuehn, Jr.
Vice President SNEC and Program Director SNEC Facility GPU Nuclear, Inc.
Route 441 South P.O. Box 480 Middletown, PA 17057-0480
SUBJECT:
SAXTON NUCLEAR EXPERIMENTAL FACILITY - DISCUSSION TOPICS FOR MAY 8, 2002, MEETING (TAC NO. MA8076)
Dear Mr. Kuehn:
We are continuing our review of your amendment request for Amended Facility License No.
DPR-4 for the Saxton Nuclear Experimental Corporation (SNEC) Facility which you submitted on February 2, 2000, as supplemented. As part of our review, we have arranged a meeting with you that is open to public observation on May 8, 2002, to discuss details of our review of your application related to pathways analysis. The details of the meeting were sent to you under separate cover. This is a follow up to our meeting of April 8, 2002.
To facilitate our discussions on May 8, 2002, please find enclosed comments and issues that were identified during our review of your License Termination Plan, response to requests for additional information and information given to us during the April 8, 2002, meeting. The enclosure is not a request for additional information and may not contain all technical issues identified by the staff. Following our meeting, we may issue a request for additional information based on the outcome of the meeting.
If you have any questions regarding this review, please contact me at (301) 415-1127.
Sincerely,
/RA/
Alexander Adams, Jr., Senior Project Manager Research and Test Reactors Section Operating Reactor Improvements Program Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation Docket No. 50-146
Enclosure:
As stated cc w/enclosure: Please see next page DISTRIBUTION:
PUBLIC RORP r/f TDragoun MMendonca AAdams WBeckner OGC EHylton FGillespie SHolmes CBassett DMatthews WEresian PIsaac PDoyle PMadden GHill (2)
ADAMS ACCESSION NO.: ML021200681 TEMPLATE #: NRR-106 OFFICE RORP:LA RORP:PM NMSS:PM RORP:SC NAME EHylton:rdr AAdams SNalluswami PMadden DATE 05/ 01 /2002 05/ 01 /2002 05/ 01 /2002 05/ 01 /2002 C = COVER E = COVER & ENCLOSURE N = NO COPY OFFICIAL RECORD COPY
DISCUSSION ISSUES FOR MEETING BETWEEN THE NRC AND SNEC STAFFS MAY 8, 2002 The following comments are based on the NRC staff review of SNECs response to NRCs request for additional information (RAI2), dated November 8, 2000.
1.
Response to RAI2 Question #3 SNECs response states that embedded piping and other components will be removed to the extent practical. However, Table 5-2 indicates that building surface DCGL values will be used for any remaining embedded piping. Given that screening DCGL values will be used for building surfaces and these screening DCGL values were not developed for this purpose, the licensee needs to justify extending the application of screening DCGL values for this purpose.
Table 5-2 also indicates that surface and volumetric concrete DCGL values will be applied in some survey units (e.g., the containment vessel). SNEC needs to clearly identify which set of DCGL values will be used. Because exposure from the concrete can occur from both surface and volumetric contamination, the more restrictive of the two sets of DCGL values should be used. It should be also noted that no DCGL values are provided for volumetric concrete.
Staff was unable to derive the area factors (specifically for Cs-137, Co-60, and Am-241) included in SNEC Calculation Report # E900-01-005. The area factors derived by staff are lower, and thus, more restrictive than those indicated in the SNEC calculation.
2.
Response to RAI2 Question #4 Not all parameters are addressed in Section II of the write-up. For example, distribution coefficients (Kd) for some isotopes and the outdoor time fraction are not included. It is important that an appropriate justification is provided for all selected values used in the analysis for key parameters. A sensitivity analysis should be used to identify the key parameters.
Given that the statistical distribution and range of parameter values used in a stochastic analysis can affect the results of the analysis, the treatment of parameters stochastically for developing DCGL values necessitates demonstrating that the statistical distribution and range of parameter values are appropriate for the SNEC site. As an alternative, the stochastic analysis can be used in identifying the key parameters affecting the calculated DCGL values; however, the specific value assigned to these key parameters will still need to be justified either in the context of what is known about the site or based upon the range of possible values. Any stochastic analysis used for either sensitivity analyses or for actually developing DCGL values, should consider potential correlation among parameters (e.g., total porosity, effective porosity, and bulk density), and should involve an evaluation of each radionuclide individually (i.e., as oppose to collectively). It should be noted that staff does not consider simply listing the parameter value used in the analysis as adequate justification for its use. Also, use of the central tendency of a range of values based on national data is generally not considered to be conservative when applied in a site-specific analysis. Such values may be appropriate for parameters for which the results are shown to be insensitive. SNECs justification for the contaminated zone thickness may be also inadequate (see staff comment, below).
Staff does not have confident that the 20 parameters listed in Table 4 (22 parameters are listed in the table, but several are listed twice) are indeed the key parameters. Based on the radionuclide mix, several parameters such as plant, meat, and milk transfer factors, saturated zone hydraulic conductivity, depth of soil mixing, and wind velocity are expected to be important, but are not included in the list in Table 4. Staff also does not agree that it is appropriate to assume that the most sensitive parameters affecting Am-241 or Cs-137 are representative or bounding of the most sensitive parameters affecting other radionuclides.
Given that a separate DCGL value is derived for each radionuclide, the most sensitive parameters affecting each radionuclide should be identified, for each radionuclide separately.
Staff also does not understand the cutoff used for establishing the list of parameters in Table 4.
Based upon the list of the most sensitive parameters affecting the dose for Am-241, several additional parameters (e.g., outdoor time fraction, soil ingestion, and density of the unsaturated zone) should have been included in Table 4.
In addition to these general concerns, staff has the following specific concerns with the analysis conducted in response to RAI2 Question #4:
SNEC needs to show that use of the lowest Kd values will provide a conservative assessment of the dose. It is not certain that use of the lowest Kd value will be conservative for radionuclides where the ground-water pathway is not important. In fact, use of the lowest Kd value could be non-conservative for radionuclides where the surface exposure pathways are important. In general, Kd should be treated as a stochastic parameter in the sensitivity analysis to determine what effect it has on the calculated dose. For isotopes where Kd is shown to be sensitive, and negatively correlated with the dose, it would be appropriate to assume that use of the minimum derived Kd value is conservative. On the other hand, where Kd is shown to be sensitive, and positively correlated with the dose, use of the minimum derived Kd value would be non-conservative.
If the slope of the ground-water ranges between 10 and 15 feet over a distance of 600 to 800 feet, the hydraulic gradient should range between 0.0125 and 0.025, instead of 0.017 to 0.019.
SNEC needs to justify the assumption that 75% of the livestock and irrigation water is derived from on-site sources. SNEC needs to explain why this is considered to be either a conservative or acceptable assumption.
SNEC needs to explain why (how) the contaminated fraction of plant food and meat parameters are identified as sensitive parameters (in Table 4); however, Table 1 indicates that these parameters were not included in the probabilistic analysis.
It is not clear why SNEC chose to use a range of values for some behavioral parameters and then elected to go with the DandD default for the basic set. Given that the DandD default is usually at the lower end of the range, this approach gives the appearance that a non-conservative value is being used, especially if the results are sensitive to the parameter (e.g., leafy vegetable consumption). If the DandD default values are considered acceptable, they should be assigned as a constant in the probabilistic analysis. On the other hand, if the assigned range and statistical distributions are considered appropriate, the selected value should be based upon that range and distribution, in which case, selection of a value at the lower end of the range cannot be considered as conservative.
SNEC needs to justify the use of a contaminated zone area of 10,000 m2; i.e., SNEC needs to indicate that this bounds the area of contamination at the site and is consistent with the assumptions made in developing survey units.
3.
Response to RAI2 Question #8 The approach taken by SNEC for developing DCGL values in response to Question #8 is different from that used in developing DCGL values in response to Question #4; therefore, it is inappropriate to combine the different sets of DCGL values in coming up with a single set of values for the site. In developing DCGL values for the subsurface material (i.e., in response to Q8), all radionuclides are evaluated together in a single analysis. This approach would tend to provide less conservative, and therefore, a less defensible set of DCGL values given that the calculated DCGL value for each radionuclide may be affected by the time when the peak dose occurs; this peak will tend to be driven by the radionuclides that have the largest contribution to the dose. This approach is acceptable only when all radionuclides included in the analysis are present. For a radionuclide that has a peak dose at a different time, occurring by itself, this approach would not be acceptable.
The approach of analyzing the radionuclides together is also not appropriate for conducting sensitivity analyses. As previously stated, the sensitivity analysis should be conducted for each radionuclide individually and not collectively. It is not clear how the three most sensitive parameters for each radionuclide, listed in Table 4-2, were derived given that the analysis included all radionuclides collectively.
SNEC needs to explain how their analysis of subsurface material appropriately represents the material being located in the saturated zone. To model this material under saturated conditions, no ground-water dilution should be assumed and all contaminants should be assumed to be available for withdrawal from the hypothetical well. Accordingly, it seems that the mass balance (MB) approach should have been used in the RESRAD analysis instead of the non-dispersion (ND) approach.
In addition to these general concerns, staff has the following specific concerns with the analysis conducted in response to RAI2 Question #8:
SNEC needs to show that use of the lowest Kd values will provide a conservative assessment of the dose (see previous comment, above). In addition, SNEC needs to justify the use of RESRAD default Kd values for Ac, Pa, Po, Ra, and Th. Further, SNEC needs to justify the use of an upper-end Kd value of five for C and H given that a recommended Kd value of one is listed in Table 3.
No basis is provided for assuming a dilution factor of 1/5 for contaminants in overburden material assumed to be brought to the surface.
The assumption that irrigation water will be derived from the shallow zone, where the contaminants are assumed to be diluted, as opposed to the deeper zone where the drinking water is assumed to be derived is not conservative and needs to be justified.
SNEC needs to provide information that was suppose to be included in Attachment A of the URS Corp. report.
As previously stated, staff does not believe that SNECs sensitivity analysis has correctly identified the appropriate list of key parameters for the site. The sensitivity analysis should consider each radionuclide individually as oppose to collectively. In addition, the fact that the external gamma shielding factor is not identified as a key parameter for Co-60, Cs-137, Eu-152, Eu-154, Eu-155, and Nb-94 in Table 4-2 raises concerns about the validity of the sensitivity results. It is also not clear why a table similar to Table 4-2 was not included for the sensitivity analyses conducted for bedrock and sediment exposures.