ML22087A019
| ML22087A019 | |
| Person / Time | |
|---|---|
| Site: | 07000925 |
| Issue date: | 03/24/2022 |
| From: | Lux J Environmental Properties Management |
| To: | Jennifer Davis, Saxton J, James Smith NRC/NMSS/DDUWP/URMDB |
| Smith J | |
| Shared Package | |
| ML22087A014 | List: |
| References | |
| Download: ML22087A019 (3) | |
Text
From: Lux, Jeff J To: Saxton, John; Smith, James; J. Paul Davis Cc: Halliburton, Bill; Hesemann, John; Clement, Daniel W
Subject:
[External_Sender] Water Level Information Date: Thursday, March 24, 2022 9:03:48 AM Attachments: 2017 Q3 Evaluated Gauging Data.xlsx 1998-04-29 Survey Data for BG 4 and Surrounding Wells.pdf SWPS-0.pdf Monitor Well 1315-1315R & TMW-09 Uranium Data.xlsx TMW-3.pdf TMW-09.pdf 2021-12-10 Comprehensive Analytical Data.xlsx 2022-03-22 Well Inventory - All Wells.xlsx
In response to your request for additional water level data, I can offer the following:
Surface Water Elevation Data You noted that there was no date for the surface water elevations for the Cimarron River reported in the July 1998 Decommissioning Plan - Ground Water Evaluation Report. The closest record I could find was a list of elevations Entitled 1998-04-29 Survey Data for Pit 3, Burial Area #4 and Surrounding Wells (attached). It includes the same elevations for the Cimarron River upstream and downstream that are presented on Drawing SWPS-0 (also attached). The data was sent by fax on April 29, 1998; the file tabulating the data was dated April 28, 1998. However; it doesnt tell on which date the elevations were measured.
To my knowledge, the elevation of the Cimarron River at the site has not been surveyed since I was appointed Manager, Planning and Regulatory Compliance for the Cimarron site in 2001. As you had noted in an earlier email, you had identified a surface water elevation at the Highway 74 bridge recorded on one date, but the nearest gauging stations are located miles upstream and miles downstream of the site, so I dont believe we can provide good surface water elevations to relate to any groundwater elevation measurements.
Groundwater Elevation Data The gauging data spreadsheet created during a 3rd quarter 2017 groundwater sampling event is also attached to this email. The depth to water date collected during this sampling event was the last such data generated for monitor wells GE-BA1-01, 02W29, 02W31, and 02W46. They were abandoned in September 2017, and the next sampling event was conducted in November 2017.
Once those monitor wells were abandoned, those locations were removed from subsequent gauging data spreadsheets, because the spreadsheets were used to provide a QC check on depth to water measurements.
The information you requested this morning indicated that the groundwater elevation data may have been measured or reported incorrectly for the following monitor wells:
TMW-24 7/31/17 TMW-19 7/13/17 (Should this have read 7/31/17? I dont have a measurement for 7/13/17.)
02W23 4/17/17 1373 2/5/16 (Should this have read 2/15/16? I dont have a measurement for 2/5/16.)
The last four columns in the spreadsheet contain formulae which calculate the mean value, standard deviation (), and the mean plus and minus 2 values for the depth to water (DTW) for each well.
The DTW is measured and compared with the mean plus and minus 2 values; if the DTW is within that range, the measured DTW is recorded. If the DTW is not within that range, it is re-measured before entering into the spreadsheet. It is possible that the DTW recorded for a specific well may be incorrect, yet fall within that range, but the simplicity of reading the measurement causes me to doubt if that happens except on rare occasions.
Coordinates for GE-BA1-01 and GE-WA-01 You were correct in that the easting and northing coordinates listed in the monitor well inventory spreadsheets for these two monitor wells had been switched. They are the correct coordinates for these two wells, but it appears the data was entered into the wrong row when creating the spreadsheet. The corrected monitor well inventory for all monitor wells (including those that have been abandoned) is attached. The top of casing elevations recorded in the monitor well inventory for these two wells was checked against the surveyors data, and they are correct.
Source Term for Uranium in Burial Area #1 During the public meeting, I indicated that the monitor well in Burial Area #1 (BA1) that may yield the best Source Concentration for uranium is Monitor Well 1315, which is located immediately north of (downgradient of) one of the four BA1 burial trenches. I thought it would have yielded the highest uranium concentration of any monitor well. Monitor Well TMW-09 (installed in 1999) is located downgradient from Well 1315/1315R, between the two proposed groundwater extraction trenches. It has long been in the heart of the uranium plume, and at one time yielded a higher uranium concentration than Monitor Well 1315 ever did.
I extracted from the spreadsheet 2021-12-10 Comprehensive Analytical Data (attached) uranium concentrations for Monitor Wells 1315/1315R (1315R replaced 1315 in 2002) and TMW-09. The data is tabulated in Monitor Well 1313-1315R & TMW-08 Uranium Data (also attached). Caution:
this spreadsheet hasnt received an independent Q-review; it must be considered a draft. I am sending it now because the I felt that the trend in data depicted on the spreadsheet is legitimate, and didnt way to pay both the time and cost to have the spreadsheet Q-reviewed before sending you this information. There are two heavy black lines in the Monitor Well 1315/1315R column:
the first indicates when Monitor Well 1315R replaced 1315, and the second line indicates when I ran out of uranium activity data but still had uranium mass concentration data. The uranium in BA1 groundwater averages approximately 1.3% enrichment, and the concentration of uranium in pCi/L is pretty close to the concentration in µg/L. I believe mass concentration data can be legitimately included for establishing trends in the data.
For your information, there were times when more than one sample from a well was collected on the same day for analysis; in those instances, I listed the average total uranium activity in the table.
If a sample was collected from TMW-09 within a few days of a sample from 1315/1315R (meaning they were collected during the same sampling event), I listed the TMW0-09 data on the date for collection of the 1315/1315R sample.
A couple of interesting observations from a cursory review of the data/graph are:
The BA1 trenches were open from 1988 and backfilled with clean soil in 1993. The uranium concentration in Monitor Well 1315 increased initially when the trench was open but declined rapidly before it was backfilled.
Unfortunately, because Monitor Well TMW-09 was installed in 1999, we have no uranium concentration data for this location between the time the trenches were excavated and 1999. The first sample collected from this well yielded the highest uranium concentration ever recorded for this location, but we cannot say this was the highest concentration ever present at this location.
Monitor Well 1316/1316R is screened in Sandstone B. I didnt tabulate the data from this well because, while it may be downgradient from the western-most burial trench, uranium concentrations have declined to less than 180 pCi/L since 1996. However, the concentration of uranium in this well rose from 287 pCi/L in 1989 to 1,880 pCi/L in 1991. It then followed a significant decline in concentration (similar to that in 1315) between 1991 and 1994, dropping to less than 200 pCi/L in 1994.
Finally, examination of the data showed that Monitor Well TMW-03 recorded uranium concentrations of 11,749 and 9,779 pCi/L in 1999. However, that monitor well was abandoned less than two months after it had been installed, so those are the only two data points we have for that location. Figure 2 from Burial Area #1 Groundwater Assessment Report (ML030360302) shows the location of TMW-03. The soil boring logs for TMW-03 and TMW-09 (attached) show that TMW-03 was located five meters east of TMW-09 (nearly co-located with TMW-09).
If you were only looking at the data for Monitor Well 1315, you might limit the source term to approximately 8,000 pCi/L. However, with a maximum concentration of 9,484 pCi/L in TMW-09 and 11,749 a little farther downgradient, I would think you could easily justify a source term of 12,000 pCi/L or more. I still believe 35 mg/L is too high, but I believe something around 12 - 15 mg/L is justifiable based on the data.
John, this may be more information than you wanted, but once I got to looking at the data, I felt I wouldnt be giving you the best information I could without overloading you with all the attached files. Please let me know if this information (minus the surface water elevation data) provides all you would want (or that may be available) for enhancement of your groundwater flow model.
P.S. - Did I use the word attached enough in this mail?
Jeff Lux, P.E.
Project Manager Environmental Properties Management LLC A Subsidiary of Burns & McDonnell Engineering Company, Inc.
405-642-5152