ML22040A151
| ML22040A151 | |
| Person / Time | |
|---|---|
| Site: | 07000925 |
| Issue date: | 02/01/2022 |
| From: | Environmental Properties Management |
| To: | NRC/NMSS/DDUWP/URMDB |
| Smith J | |
| Shared Package | |
| ML22040A147 | List: |
| References | |
| Download: ML22040A151 (5) | |
Text
REQUESTS FOR INFORMATION RELATED TO NRC COMMENTS FROM THE PRE-APPLICATION AUDIT FOR FACILITY DECOMMISSIONING PLAN - REV 3 REQUESTS FOR SUPPLEMENTAL INFORMATION RSI Last Paragraph on Page 8-48, First Paragraph on Page 8-49, and First Paragraph on Page 15-9 The NRCs first comment indicates that NRC believes the commitment in Section 8.8 of the decommissioning plan to conduct four quarters of groundwater monitoring is considered to be an unreasonable request, and that the text implies that this sampling will be performed pro forma. I can only assume that the use of the word request in the DP text was taken to mean that the collection of these samples is not required but will be performed as a courtesy to the NRC. There is nothing in the text that states or implies that this is the case. That text was written using the exact same terminology that the NRC used in the April 22, 2013, letter to which the comment refers, which read, the NRC staff requests that the post-remediation monitoring plan leading to license termination includes four calendar quarters of monitoring for Tec-99 to be collected, shortly before requesting license termination, to confirm that previous concentrations have remained below NRCs DCL.
The NRCs comment also emphasized by underlining that this sampling should document existing residual contamination at the time of license termination. It is our understanding that collecting and analyzing groundwater samples for Tc-99 during four quarterly sampling events during post-remediation monitoring provides exactly the data that the NRC requested in the April 2013 letter.
Two previous versions of the decommissioning plan have been accepted for detailed technical review with the same commitment to collect and analyze groundwater samples for Tc-99 during the first four quarterly post-remediation monitoring events; does this comment indicate that this commitment is in some way deficient?
NRC staff also recommends that the first full paragraph on page 15-9 be removed, without explaining the basis for that recommendation. That paragraph is identical to the last full paragraph on page 4-3 of the DP. It simply states that the EPA criterion for Tc-99 in groundwater is 900 pCi/L, and that the DEQ has adopted that value as their criterion for the release of the site without restriction. As previous paragraphs in RSI-1 pointed out, the MOU between the NRC and the EPA requires the NRC to notify the EPA regarding residual contamination at license termination. It seems logical to provide this information in the DP just as the EPA criterion for uranium in groundwater, also adopted by the DEQ as their unrestricted release criterion, is provided. What is the justification for NRC staffs recommendation to remove that paragraph from page 15-9 of the DP, while accepting it on page 4-3 of the DP?
RSI Chapter 9.5 Schedule Changes This comment implies that the request and justification for an alternate schedule appears only in the cover letter for the response submittal, but not in the DP. It recommends that the request and the justification for requesting an alternate schedule be included in the DP.
The last paragraph in Section 9.5 of the DP reads, The schedules presented herein do not comply with the two-year time frame for decommissioning specified in 10 CFR 70.38(g)(4)(vii). The schedules presented herein demonstrate the need for an alternative schedule in accordance with 10 CFR 70.38(g)(2).
The licensee herein requests NRC approval of this alternative schedule.
If schedules for pre-construction, construction, remediation, and post-remediation activities, showing that decommissioning cannot be completed within 15 years, do not provide the needed justification, please let us know what additional justification is needed.
RSI-3, Second and Third Paragraphs The schedule and the cost estimate in the DP was based on an assumption that groundwater extraction, treatment, and injection and discharge would continue in the western area (WA) until groundwater in Burial Area #1 (BA1) complies with the NRC criterion. The cost savings associated with shutting down the WA systems were believed to be a small fraction of the cost of continuing to man the site, maintain the building, and operate the BA1 remediation systems. We believed the removal of additional uranium (stated in the DP as the greatest removal of contaminant mass) justified the incremental cost increase.
It appears that the NRC interpreted this statement to imply that the goal of the remediation was to achieve the greatest removal of contaminant mass rather than to obtain license termination. If the NRC would prefer to leave as much uranium in the groundwater as possible while achieving the NRC criterion, so that it is clear that the primary objective is to achieve the NRC criterion, the DP can be revised to state that all WA systems will be shut down as soon as the NRC criterion are achieved in all WA remediation areas.
RSI-5 It appears that the NRC takes exception to the statement in the DP that says the NRC requires 12 quarters of post-remediation groundwater monitoring, when license condition 27(c) requires only eight quarters of post-remediation monitoring. We can only assume that this comment is a result of the complete changeover of NRC staff associated with the Cimarron license.
Between 2003 and 2009, the licensee submitted several decommissioning plans proposing to use in situ biological immobilization to reduce the concentration of uranium in groundwater to less than the NRC criterion. The former NRC Project Manager (PM) was Ken Kalman, who served as the PM from 1996 through much of 2020. During numerous telephone calls with the previous and current licensees, Mr.
Kalman stated that the eight quarters of post-remediation groundwater monitoring required by license condition 27(c) was based upon monitored natural attenuation (MNA) being the means by which groundwater would achieve the NRC criterion.
Based on guidance from the two previous hydrogeological support staff, Mr. Kalman was concerned that groundwater extraction will create cones of depression, and the return of groundwater elevations to pre-remediation levels post-remediation will provide an opportunity for uranium in the unsaturated zone created by pumping to desorb and result in a rebound in uranium concentrations. Uranium concentrations could rebound for the first quarter or two after terminating groundwater extraction. Consequently, adding four quarterly post-remediation sampling events should be sufficient to generate eight quarters of data showing that after rebounding, uranium concentrations still do not exceed the NRC criterion.
Between 2000 and 2020, the licensee requested that the license be amended several times to remove from the license tie downs that no longer apply to the site, to revise the environmental monitoring program, etc. Mr. Kalman was not willing to amend the license to reflect the current status of site decommissioning until the license could be amended to include a groundwater remediation plan.
Unfortunately, neither the NRC nor the licensee documented these conversations.
If the NRC desires, the DP can be revised to provide only eight quarters of post-remediation monitoring.
If the issue is that the NRC objects to the statement that the NRC requires 12 quarters of post-remediation monitoring because the NRC never documented that desire, there is no reason to revise the DP. If there is in this section of the DP some deficiency that would impact the detailed technical review of the DP, please advise us accordingly.
RSI-6 A)
It appears that in generating this comment, the NRC reviewer was reading the response letter that was initially placed on the Microsoft TEAMS site. In an email dated November 23, 2021, I notified you and all the NRC reviewers that I had replaced the letter of submittal on the Microsoft TEAMS site, as a found some incorrect numbers, section references, etc. The letter of submittal that I uploaded to the Microsoft TEAMS site replaced the references to Tables 2-11 through 2-13 with references to Tables 2-10 through 2-12. There is no Table 2-13 in the DP tables. The calculation of the mean values in all three tables will be reviewed and revised as appropriate.
RSI-6 B)
Im not sure if this is just informing us that the October 4, 2021, letter of submittal for a CD containing Excel and PDF files is not in ADAMS, or if this letter should be electronically submitted to be uploaded to ADAMS. Either way, this does not appear to be identifying a deficiency in the DP; please clarify if this is the case.
It was the licensees understanding that a licensee cannot electronically submit an Excel file to the Document Control Desk for uploading to ADAMS, but that the NRC PM could work with NRC personnel to have the Excel and PDF files uploaded to ADAMS. Does the NRC PMs collaboration with Document Control Desk personnel include the cover letter in the files that would be uploaded? Please advise if you want the cover letter to be submitted to the Document Control Desk.
RSI First Paragraph This paragraph appears to be saying that the DP is deficient because it doesnt provide more information on the elevation of the 100-year flood. Previous versions of the DP, which cited a 100-year elevation of 960 feet above mean sea level (AMSL) had been accepted for detailed technical review. After receiving previous requests for information, other information was presented that indicated that the 100-year flood elevation may be lower (951 feet AMSL). This comment state than a 1993 measurement recorded a peak elevation (for that flood event) of 945.8 feet AMSL.
Why is it necessary to more precisely determine the 100-year flood elevation? Monitor wells in the floodplain have been inundated multiple times during the past 20 years. J-plugs have been installed in all monitor wells with a top-of-casing elevation below 960 feet AMSL. The NRCs concern appears to be the inundation of monitor wells in the floodplain during flood events. If the NRC could explain why more study/research should be performed to more precisely define the 100-year flood elevation, additional resources could be spent conducting such evaluation. However, it is not clear that any changes would be made to the DP if the 100-year flood elevation is a few feet above or below the 951-foot AMSL elevation currently referenced in the DP; in short, it doesnt appear that the benefit of more evaluation is worth the cost.
RSI Second Paragraph The NRC desires justification for using the low-water median flow as the benchmark rather than more commonly used benchmarks. The purpose for this calculation was to address a comment by NRC staff that the first paragraph of Section 5.6.4 in DP - Rev 2 implied that the reason for remediating the groundwater was to protect the Cimarron River. That paragraph was revised to clarify that groundwater remediation is needed to comply with license criteria. The dilution calculation was only provided to demonstrate that even without groundwater remediation, licensed material would never measurably impact the Cimarron River.
The low-water median flow was easily available and had been acceptable to hydrogeological review staff during two previous acceptance reviews of the DP. Using the low-water median flow to calculate dilution factors yielded dilution of greater than 1,000:1 for the WA and greater than 2,000:1 for BA1. With this degree of dilution, licensed material would never be detectable in the Cimarron River even with no groundwater remediation.
If the NRC is concerned that the use of more commonly used benchmarks such as the 7-day average low flow every 2 years could so reduce dilution factors that licensed material would materially impact the Cimarron River, additional time and money can be spent to refine that calculation. However, because that calculation does not appear in the DP, it is probably not worth the additional effort to further evaluate various benchmarks for low flow unless NRC staff feels it could result in the reduction of dilution factors by more than an order of magnitude.
REQUESTS FOR CLARIFICATIONS Soil Regarding Subareas F, G, and N, the NRC states that there has been no regulatory action to release these subareas from the license and they are therefore not released from license controls as stated by the licensee. Final status surveys and confirmatory surveys have been performed which demonstrated to the NRCs satisfaction that both surface and subsurface soils comply with license criteria for soils.
In addition, the February 16, 2011, License Transfer Order (published in the Federal Register on February 28, 2011), which transferred license SNM-928 to the CERT states, Final status surveys and confirmatory surveys have confirmed that Subareas G and N are releasable for unrestricted use, but NRC has determined that these areas should not be released until groundwater remediation is complete. Because groundwater exceeds license criteria in Subarea F, this area cannot be released for unrestricted use until groundwater remediation is complete. Because the NRC has documented that Subareas G and N are releasable for unrestricted use, these portions of the site, as well as all the areas that have been released from the licensed, should be exempt from license controls.
The NRC has released from the license areas within which uranium concentrations exceed license criteria for groundwater. Consequently, EPM has submitted a license amendment request to bring the appropriate portions of the site back under license. There should be no need to conduct any radiological surveys for soil in areas that have been released from the license; for the NRC to require continuing surveys to evaluate soil against the decommissioning criteria is unwarranted.
The licensee has proposed to continue to conduct radiological surveys to identify material that may have been buried of which no one currently involved with the site may be aware. The reason for conducting these surveys is not to continue to evaluate soils against decommissioning criteria. We acknowledge that gamma surveys cannot demonstrate compliance with decommissioning criteria for soil, but gamma surveys can identify non-native material brought to the surface that needs to be further evaluated. For example, when a piece of concrete in the Uranium Pond #1 area was brought to the surface during the excavation of a pilot test trench in 2017, a gamma survey identified a spot of contamination; this triggered surface contamination measurements that identified an area that exceeds surface contamination limits.
There is no real justification for conducting the survey of the sediment/spoils mixture that we have agreed to perform. We will be taking soil from two areas in which the soil has already been accepted by the NRC as complying with license criteria, and which have been released from the license, and surveying them as though they are potentially contaminated above license criteria. We are bending over backward trying to satisfy NRCs concerns, and this is costing time and money that the NRC should be committing to remediating groundwater, not revisiting soil that has already been released from the license.
We will be willing to revise the DP so that there is no distinction between soil from one foot to three feet in depth and greater than three feet in depth, performing a gamma survey and further investigating any material exceeding 2 times background. We will be willing to revise the DP so that there is no distinction between soil from one foot to three feet in depth and greater than three feet in depth, performing an exposure rate survey and further investigating any material exceeding the license criterion of 10 µR/hr at one meter from the soil. However, the NRC should explain why radiological surveys of soil that the NRC has documented are releasable for unrestricted use should be surveyed at all, because the additional expense associated with continuing to conduct such surveys diverts needed funds from the remediation of groundwater which does exceed license criteria.