ML070320450
| ML070320450 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 09/25/2006 |
| From: | Adams W Oak Ridge Institute for Science & Education |
| To: | Tanya Smith NRC/FSME |
| References | |
| RFTA 06-006 | |
| Download: ML070320450 (10) | |
Text
OAK RIDGE INSTITUTE FOR SCIENCE AND EDUCATION September 25, 2006 Mr. Theodore Smith Mail Stop: T-7F27 Division of Waste Management U.S. Nuclear Regulatory Commission 11545 Rockville Pike Rockville, MD 20852
SUBJECT:
CONFIRMATORY SURVEY RESULTS FOR SURVEY UNITS 9304, 9527 AND 9530 AT THE CONNECTICUT YANKEE HADDAM NECK PLANT, HADDAM, CONNECTICUT [DOCKET NO. 50-0213; RFTA NO. 06-006]
Dear Mr. Smith:
The Oak Ridge Institute for Science and Education (ORISE) performed confirmatory survey activities within Survey Units 9304-0001 and 9304-0002, 9527-0003 and 9527-0004, and 9530-0001 through 0004 at the Connecticut Yankee Haddam Neck Plant in Haddam, Connecticut, on August 22 and 23, 2006.
Tiffs survey activity was requested and approved by the U.S. Nuclear Regulatory Commission (NRC).
Confirmatory survey activities included gamma surface scans and soil sampling. Enclosed are the results documenting these survey activities.
If you.have any questions or comments, please direct them to me at 865.576.0065 or Scott Kirk at 865.574.0685.
Sincerely, Wade C. Adams Health Physicist/Project Leader Survey Projects WCA:ar Enclosure c:
B. Watson, NMSS/DWMIEP/DD/SP 7E18 E. Ablequist, ORISE E. Knox-Davin, NRC/NMSS/TWFN 8A23 S. Kirk, ORISE L. Kauffman, NRC/Region I M. Miller, NRC/Region I J. Kottan, NRC/Region I File/1698 Distribution approval and concurrence: I niti ~s--
Technical Management Team Member Laboratory Manager Quality Manager Voice: 865.576.0065 Fax: 865.241.3497 E-mail: AdamsW@orau.gov
CONFIRMATORY SURVEY RESULTS FOR SURVEY UNITS 9304, 9527 AND 9530 AT THE CONNECTICUT YANKEE HADDAM NECK PLANT HADDAM, CONNECTICUT INTRODUCTION The U.S. Nuclear Regulatory Commission (NRC) requested that the Oak Ridge Institute for Science and Education (ORISE) perform confirmatory surveys of Survey Units 9304-0001 and 9304-0002, 9527-0003 and 9527-0004 and 9530-0001 through 9530-0004 at the Connecticut Yankee (CY)
Haddam Neck Plant (HNP) in Haddam, Connecticut (Figure 1). Confirmatory surveys were performed on August 22 and 23, 2006. Areas of the HNP included in the survey-are depicted m Figure 2.
PROCEDURES Confirmatory surveys were performed in accordance with a site-specific survey plan that was submitted to and approved by the NRC (ORISE 2006a). Survey activities were implemented in accordance with ORISE Survey Procedures and Quality Assurance Manuals (ORISE 2006b and 2005).
The survey activities included gamma surface scans that were performed over 10 0 % of accessible portions of the grounds within Survey Unit (SU) 9304-0002 and 25 to 50% within SUs 9304-0001, 9527-0003, 9527-0004 and SUs 9530-0001 through 9530-0004. Sodium iodide (NaD) scintillation detectors coupled to ratemeters with audible indicators were used for scanning. Accessibility to some areas was restricted due to safety concerns for ORISE personnel.
Soil samples were collected from two biased locations within SU 9527-0004 and one biased location within SU 9304-0002. Soil samples were also collected at nine randomly selected locations within SUs 9304-0001 and 9304-0002 (Figures 3 and 4). Soil samples were not collected within SU 9527-0003 based on the gamma scan and previous soil sample results. At the direction of the NRC site representative, soil samples were not collected within SU 9530-0001 through 9530-0004 since CY personnel were in the process of collecting final status survey (FSS) samples.
SAMPLE ANALYSIS AND DATA INTERPRETATION Radiological data and sample media were returned to ORISE's laboratory in Oak Ridge, TN for analysis and interpretation. Radioassays were performed in accordance with the ORISE Laboratory Procedures Manual (ORISE 2006c). Soil samples were analyzed by gamma spectroscopy for the primary radionuclides of interest (i.e., Co-60 and Cs-137). However, spectra were also reviewed for other gamma-emitting fission and activation products associated with the HNP and other identifiable total absorption peaks. Soil sample results were reported in units of picocuries per gram (pCi/*.
Connec6cut Yankee, Open Land Areas 1698\Reports\2006-09-25 Confirmatory Survey Results.doc
FINDINGS AND RESULTS Gamma surface scans identified two locations of elevated radiation levels in SU 9527-0004 that were previously identified during the April 2006 ORISE confirmatory survey activities (ORISE 2006d).
Gamma scans also identified two locations of elevated radiation levels within SU 9304-0002; however, both of these locations were previously identified by CY personnel. One of the areas included elevated radiation in a rock and in the soil beneath the rock. ORISE requested that CY personnel determine the spectrum of gamma energies at these four locations using the Exploranium GR-130 Minispec. CY personnel performed a 10-minute count at each location and determined that the elevated gamma radiation levels were from naturally occurring radioactive materials (NORM).
No elevated gamma activity was detected within the remaining SUs. ORISE personnel collected biased soil samples from three of the four locations. Ten soil samples were collected from randomly selected locations within SUs 9304-0001 and 9304-0002.
The range of radionuclide concentrations for the twelve soil samples collected within the subject survey areas by ORISE are as follows:
Range of Radionuclide Concentrations in Soil Samples (pCi/g)
Survey Units' Co-60 Cs-137 9304-0001 -0.01 to 0.02 -0.01 to 0.05 9304-0002 -0.01 to 0.00b 0.00 to 0.03 9527-0004 0.01 to 0.09 2.35 to 2.36
'Refer to Figures 3 and 4.
'Zero values due to rounding.
A complete listing of the confirmatory sample results is presented in Table 1.
COMPARISON OF SOIL SAMPLE RESULTS AGAINST THE RELEASE CRITERIA A comparison of the soil sample results against the site-specific operational derived concentration guideline levels (DCGLs) for Co-60 (1.22 pCi/g) and Cs-137 (2.53 pCi/g) per the Final Status Survey (FSS) Release Records for each SU was performed to determine whether or not the site was suitable for unrestricted release (CYAPCO <no date provided>). The confirmatory survey activities determined that detectable Cs-137 concentrations, approaching the site-specific operational soil DCGLs, were present in two soil samples within the East Mountain Side SU 9527-0004. These two soil samples (Samples 1698S0023 and 1698S0024) were collected just above a granite rock surface at a depth of approximately 0.8 cm. During the April 2006 ORISE survey activities, soil samples collected from these locations also indicated the presence of Cs-137 concentrations that exceeded the Operational DCGLs (ORISE 2006d). A review of the FSS report for this SU indicates that the ORISE survey data corroborates the CY FSS data; samples from the previous ORISE survey activities in these locations exceeded the Operational DCGL. NRC, ORISE and CY personnel discussed this issue during several teleconferences and CY personnel were to revise the FSS report for SU 9527-0004 to indicate the reason for the elevated Cs-137 concentrations in this SU. The radionuclide Connecticut Yankee, Open Land Areas 2 1698\Reports\2006-09-25 Confi-matory Survey Results.doc
concentrations for all the remaining soil samples were below their respective Co-60 and Cs-137 Operational DCGLs.
Based upon ORISE's confirmatory survey results, the radionuclide concentrations present Mithe soil samples for SUs 9527-0004, 9304-0001 and 9304-0002 are commensurate with the release criteria specified within their respective FSS Release Records (CYAPCO 2005). Therefore, it is ORISE's opinion that the radiological conditions for these SUs are suitable for unrestricted use in accordance with the clean up criteria in the License Termination Plan (LTP) (CYAPCO 2005).
Connecticut Yankee, Open Land Areas 3 1698\Reports\2006-09-25 Confirmatory Survey Results.doc
1698-001 (1)
Connecticut Yankee Haddam Neck Plant
+/-
NOT TO SCALE FIGURE 1: Location of the Connecticut Yankee Haddam Neck Plant - Haddam, Connecticut Connecticut Yankee, Open Land Areas 4 C1698\Reports\2006-09-25 Confirmatory Survey Results.doc
1698-002 (3) 9527-0003 1052,7-0002 9527,-0001 9530-0001 tlhrough 9304-0001 and 9304-0002 9530-0004 AREAS SURVEYED NOT TO SCALE FIGURE 2: Plot of the Connecticut Yankee Haddam Neck Plant Site Indicating Areas Surveyed Connecticut Yankee, Open Land Areas 1698\Reports\2006-09-25 Confirmatory Survey Results.doc 5
1698-009 (1) 9304-0002 1698S0031 1698S0033 98S0032 16-Q 16981S0034 SAMPLING LOCATIONS EX] # SURFACE SOIL NOT TO SCALE FIGURE 3: Survey Units 9304-0001 and 9304-0002 - Soil Sampling Locations Connecticut Yankee, Open Land Areas 6 1698\Rep'orts\2006-09-25 Confirmatory Survey Results.doc
1698-008 (x) 1698S0023
[]
1698SO024 SAAMILING LOCATIONS
- SOIL SAMPLE NOT TO SCALE FIGURE 4: East Mountain Side, Survey Unit 9527-0004 - Soil Sampling Locations Connecticut Yankee, Open Land Areas 7 1698\Reports\2006-09-25 Confirmatory Survey Results.doc
TABLE 1 CONFIRMATORY SURVEY RESULTS FOR SURVEY UNITS 9304 AND 9527 AT THE CONNECTICUT YANKEE HADDAM NECK PLANT HADDAM, CONNECTICUT Radionuclide Concentrations (pCi/g)
Sample Locationa Co-6ob Survey Unit 9304-0001 1698S0030 -0.01 +/- 0.03c 0.01 +/- 0.03 1698S0031 -0.01 +/- 0.02 -0.01 +/- 0.02 1698S0032 0.01 +/- 0.02 0.03 + 0.03 1698S0033 0.02 +/- 0.02 0.02 +/- 0.02 1698S0034 -0.01 +/- 0.02 0.05 +/- 0.03 Survey Unit 9304-0002 1698S0025 0 .0 0 d + 0.03 0.00 +/- 0.02 1698S0026 0.00 +/- 0.03 0.02 +/- 0.02.
1698S0027 -0.01 +/- 0.03 0.03 +/- 0.02 1698S0028 0.00 +/- 0.02 0.02 +/- 0.02 1698S0029 -0.01 +/- 0.02 0.02 +/- 0.02 Survey Unit 9527-0004 1698S0023e 0.09 +/- 0.03 2.35 +/- 0.15 1698S0024e 0.01 +/- 0.05 2.36 +/- 0.20
.Refer to Figures 3 and 4.
bThe LTP Base Case DCGL values are 3.81 pCi/g for Co-60 and 7.91 pCi/g for Cs-137. The FSS Operational DCGL values are 1.22 pCi/g for Co-60 and 2.53 pCi/g for Cs-1 37.
cUncertainties represent the 95% confidence level, based on total propagated uncertainties.
dZero values due to rounding.
eThese two soil samples were collected just above granite rock surfaces at a depth of approximately 0.8 cm.
Connecticut Yankee, Open Land Areas 8 1698\Reports\2006-09-25 Confirmatory Survey Results.doc
REFERENCES Connecticut Yankee Atomic Power Company (CYAPCO). Draft-CYAPCO Final Status Survey Release Records, East Mountain Side, Survey Units 9527-0001, 9527-0002, 9527-0003, and 9527-0004. Connecticut Yankee Haddam Neck Plant, Haddam, Connecticut; Reference dates not provided, Connecticut Yankee Atomic Power Company. License Termination Plan, Connecticut Yankee Decommissioning Project, Haddam Neck Plant, Revision 3. Haddam, Connecticut; August 2005.
Oak Ridge Institute for Science and Education (ORISE). Quality Assurance Manual for the Environmental Survey and Site Assessment Program. Oak Ridge, Tennessee; July 29, 2005.
Oak Ridge Institute for Science and Education. Proposed Confirmatory Survey Plan for the Remaining Structural Surfaces, Embedded Piping, Standing Water and Open Land Area Survey Units, Connecticut Yankee Decommissioning Project, Haddam, Connecticut [Docket No. 50-0213; RFTA No. 06-006]. Oak Ridge, Tennessee; April 21, 2006a.
Oak Ridge Institute for Science and Education. Survey Procedures Manual for the Environmental Survey and Site Assessment Program. Oak Ridge, Tennessee; August 7, 2006b.-
Oak Ridge Institute for Science and Education. Laboratory Procedures Manual for the Environmental Survey and Site Assessment Program. Oak Ridge, Tennessee; April 18, 2006c.
Oak Ridge Institute for Science and Education. Confirmatory Survey Results for the East Mountain Side at the Connecticut Yankee Haddam Neck Plant, Haddam, Connecticut [Docket No. 50-0213; RFTA No. 06-006]. Oak Ridge, Tennessee; July 18, 2006d.
Connecticut Yankee, Open Land Areas 9 1698\Reports\2006-09-25 Confirmatory Survey Results.doc