Attch_4_-_Final_Status_Survey_Report_26_Jun_26_0001.pdf

NOAA NATIONAL MARINE

FISHERIES SERVICE

NORTHWEST FISHERIES

SCIENCE CENTER

FINAL STATUS SURVEY REPORT

ROOM 413E

2725 MONTLAKE BLVD. EAST

SEATTLE, WASHINGTON 98112

P R E P A R E D B Y N W R A D I A T I O N S E R V I C E S , I N C .

L O U I E C U E V A , R R P T

J O S E P H S K O V R O N , M B A

J U N E 2 6 , 2 0 2 3

NOAA NWFSC – Final Status Survey Report

F I N A L S TAT U S S U RV E Y

TABLE OF CONTENTS

Table of Contents

Acronyms and Abbreviations

1.0 Introduction

1.1 Historical Information

1.2 Historical Radionuclide Usage

1.3 Historical Contamination Surveys and Contamination Events

1.4 Radionuclide(s) of Interest

1.5 General Laboratory and Use Area Descriptions

2.0 Release Criteria And Release Authority

2.1 Release Criteria For Fixtures and Equipment

2.2 Screening and Clearance Criteria for Permanent Building Surfaces

2.3 Release Authority

3.0 Survey Units and Survey Plan

3.1 Survey Unit Identification

3.2 Survey Unit Classification

3.3 Survey Plan

3.4 Liquid Scintillation Wipe Sample Preparation and Counting

4.0 Survey Results

4.1 Survey Results

4.2 Summary and Conclusion

4.3 Release Authority

5.0 Final Status Survey Report Approval

6.0 References

Appendix A – Survey Unit Schematic Diagrams

Appendix B – FSS Survey Data

Appendix C – Fixtures & Equipment Release Survey Data

Appendix D – Wipe Sample counting data

Appendix E – Calibration Certificates

Appendix F – Survey Photographs

ACRONYMS AND ABBREVIATIONS

DCGL Derived Concentration Guideline level

NRC United States Nuclear Regulatory Commission

FSS Final Status Survey

License Radioactive materials license 46-06377-04, issued to NWFSC.

MARSSIM Multi-Agency Radiation Survey and Site Investigation Manual, NUREG-1575 Vol 1-3

NWFSC NOAA Northwest Fisheries Science Center

RSO Radiation Safety Officer

SNC Self-Normalization and Calibration Protocol

SP Survey Plan

SU Survey Unit

1 .0 INTRODUCTION

1.1 HISTORICAL INFORMATION

NOAA Northwest Fisheries Science Center (NWFSC) has been issued a radioactive materials license (License) by the United States Nuclear Regulatory Commission (NRC). The License, 46-06377-04, as amended, is a specific radioactive materials license. The License authorizes (5) five locations for use/storage: NWFSC’s facility is located at 2725 Montlake Blvd. East, Seattle, Washington. The named Radiation Safety Officer (RSO) is Thanh Minh Tring, P.E.

The License authorizes the following radionuclides, forms, and annual possession limits at both locations:

• Hydrogen-3 (3H) Any 200 mCi β emission

• Carbon-14 (14C) Any 50 mCi β emission

• Iodine-131 (131I) Any 1 mCi γ emission

• Phosphorus-32 (32P) Any 40 mCi β emission

• Sulfur-35 (35S) Any 2 mCi β emission

• Iodine-125 (125I) Any 10 mCi γ emission

License section 9 authorized the use of licensed material for research and development as defined in 10

CFR 30.4.

The intent of the decommissioning activity is to release only laboratory room 413E location for unrestricted use and subsequently removal from the License. The remainder of the use/storage locations listed on the License will remain intact.

1.2 HISTORICAL RADIONUCLIDE USAGE

Room 413E is a common laboratory area used for radioactive materials work until work ceased in 2022.

Room 413E is posted ‘Caution – Radioactive Materials’ and contains a laboratory sink with work benches situated throughout the main floor space. The south side of the room is occupied by a biological safety cabinet. A free-standing table with a PerkinElmer Top Count microplate reader, full-sized refrigerator and an under-counter storage freezer were also present in the laboratory space.

NWFSC radiation safety program records indicate the last use of 3H occurred in February 2022. The last receipt of radioactive material into Room 413E occurred in June 2014.

A sink utilized for radioactive materials disposal (“Hot Sink”) is also located in the room. Historical information on nuclide release from this sink was recorded and provided to the RSO on a monthly basis.

According to said records the last discharge of radioactive material last occurred in July 2019.

Additionally, the sink was labeled with ‘Caution – Radioactive Materials’ tape.

1.3 HISTORICAL CONTAMINATION SURVEYS AND CONTAMINATION EVENTS

NRS personnel reviewed recent quarterly radioactive materials contamination surveys. Research activities were not noted as occurring within the space since 2019, nor was surface contamination on benches and equipment ever identified in the reviewed survey records. NWFSC personnel and the RSO indicated there was no known events or spills that occurred during active radioactive materials use.

1.4 RADIONUCLIDE(S) OF INTEREST

The room contained licensed radioactive material in dispersible form, as identified above in Section 1.1, in the form of 3H and 14C labeled compounds. Thus, the nuclides of interest are 3H and 14C.

1.5 GENERAL LABORATORY AND USE AREA DESCRIPTIONS

Historical use and storage locations within the general laboratory area are depicted in Figure 1. The south side of the room was utilized for radioactive materials work. Ancillary equipment such as freezers and sink were also included in the L-shaped area considered as part of the survey unit.

Figure 1 - Historical Use Areas (highlighted)

At the time of this Final Status Survey (FSS), Room 413E was devoid of radioactive materials. Stored license-exempt 96-well calibration standards, potentially contaminated benchtop equipment, cell harvester and waste collection bottles and spill trays were packaged as radioactive waste.

All remaining consumable supplies, documentation, and other items not associated with radioactive materials operations and non-radioactive reagents were removed from the work area immediately prior to the execution of the FSS. This FSS report also documents the release of fixtures and equipment in accordance with the criteria described as screening levels for Group 4 (low energy beta-gamma emitters) in Table 1 from ANSI/HPS N13.12-2013 [1]. In practice, any items that demonstrated contamination distinguishable from background would have been disposed as radioactive waste.

2 .0 RELEASE CRITERIA AND RELEASE AUTHORITY

2.1 RELEASE CRITERIA FOR FIXTURES AND EQUIPMENT

The release criteria for fixtures and equipment will be 6,000 dpm/100 cm2, based on the screening levels for surface contamination in ANSI/HPS N13.12-2013 Table 1 – Group 2. Group 2 is utilized as 14C is the limiting radionuclide. “Thus, one can reasonably expect typical doses to members of the public from releases associated with the screening levels to be less than about 10 μSv/y (1.0 mrem/y).” [1]

2.2 SCREENING AND CLEARANCE CRITERIA FOR PERMANENT BUILDING SURFACES

The screening levels established ANSI/HPS N13.12-2013 served as a conservative surrogate derived concentration guideline level (DCGL) for permanent building surfaces. The screening level, 6,000 dpm/100 cm2, corresponding to Group 2 in Table 1 from ANSI/HPS N13.12-2013 [1] were used as the clearance criterion. “Thus, one can reasonably expect typical doses to members of the public from releases associated with the screening levels to be less than about 10 μSv/y (1.0 mrem/y).” [1].

Based on historical information, no fixed or removable residual contamination results distinguishable from background was anticipated. If any contamination were identified, it was anticipated that it would be easily removed by simple wiping with a moist paper towel and, as necessary, a decontamination solution.

Additionally, should fixed contamination or removable surface contamination above the screening criteria be identified, then a nuclide-specific and site-specific DCGL as identified in the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), NUREG-1575 [2] would be developed.

2.3 RELEASE AUTHORITY

As Room 413E held specifically-licensed radioactive materials, the NRC is the release agent. Should identified contamination in the room meet the relevant release criteria described in Section 2.2, the NRC must then be petitioned to release Room 413E for unrestricted usage.

3 .0 SURVEY UNITS AND SURVEY PLAN

3.1 SURVEY UNIT IDENTIFICATION

For the purposes of this SP, the Survey Unit (SU) was as follows:

• Survey Unit 1 – Room 413E

SU-1 encompasses the entire laboratory room where the walls of Room 413E provided a logical boundary.

The Hot Sink is logically bounded by the sink deck, cabinetry, and surrounding floor area and common equipment. Schematic diagram of the SU is presented in Appendix A – Survey Unit Schematic Diagram.

Areas of the lab that were historically not used for radioactive materials work were surveyed to a lesser extent as focus was given to areas immediately surrounding work areas and storage equipment.

3.2 SURVEY UNIT CLASSIFICATION

MARSSIM [2] allows for a SU to be tentatively identified as Impacted and Non-Impacted based on the historical presence of radioactive material within the SU. Additionally, the Impacted SUs are further divided into Class 1 through 3 based on the likelihood of radioactive material contamination and the residual activity present as a function of the DCGL. The SU Class was based upon: (1) A consideration the radionuclides that were present based on radionuclide analyses (and other media) samples; and (2) A determination of the limiting radionuclide that was present, based on its surface (not volumetric) concentration compared with its DCGL.

Based on the nuclides of interest, NRS personnel’s experience with research laboratory operations generally, and using MARSSIM methodology, the SU is classified as Impacted - Class 3, which allows for considerable surveyor discretion.

3.3 SURVEY PLAN

As noted in Section 1.4, the nuclides of interest are 3H and 14C. In the interest of conducting a comprehensive current-year survey, and consistent with the nuclides in dispersible form listed on the License, any gamma / x-ray / beta emission distinguishable from background was considered due to the License authorizations. The survey instruments and survey techniques are as follows:

• Direct measurement instruments were operability tested with a 137Cs instrument check source prior to use and were in current calibration.

• Background count rates for direct measurement instrumentation were measured in an appropriate low-background area near the SU of interest.

• Laboratory work surfaces, floors, and laboratory equipment and supplies were scan-surveyed with a Ludlum 3 coupled to a 44-3 NaI scintillator to determine the presence of gamma / x-ray emitting radionuclides.

• Laboratory work surfaces, floors, and laboratory equipment and supplies were scan-surveyed with a Ludlum 14C coupled to a 44-9 GM detector to determine the present of beta emitting radionuclides.

• Laboratory work surfaces, floors, and laboratory equipment and supplies were scan-surveyed with a Bicron MicroRem survey meter to identify any exposure rate distinguishable from background.

• Wipe samples were taken using National Diagnostic Nuc-Wipes rubbed in a random serpentine fashion across approximately 100 cm2 of the subject surface while applying moderate pressure.

The Nuc-Wipes were immediately placed within a liquid scintillation counting vial.

• Surveyor discretion was utilized as to the number and location of wipe samples and scanning surveys.

• Laboratory casework and equipment were visually inspected for the presence of any apparent radioactive materials or tools and supplies associated with radioactive materials operations.

Measurement/detection sensitivities are presented in Table 3 for hand-held survey instruments and sample counting equipment. Only LSC wipe sample results were used as the basis for meeting the release criterion for 3H and 14C.

Table 1 - Instrument Performance & Detection Capabilities1

Instrument Background Efficiency LLD (net)

MDC

(per 100 cm2)

Ludlum 3 w/ 44-3 NaI 150 cpm 15.2% (129I) N/A N/A

Ludlum 14C w/ 44-9 GM 50 cpm 2.6% (14C) N/A N/A

PE Tricarb 2910 TR 7 cpm 59.3% (3H) 15 cpm 26 dpm

10 cpm 91.1% (14C) 26 cpm 19 dpm See Appendix E – Calibration Certificates

3.4 LIQUID SCINTILLATION WIPE SAMPLE PREPARATION AND COUNTING

Liquid scintillation wipe samples were analyzed with a PerkinElmer Tricarb 2810 TR liquid scintillation counter (LSC), SN 095064.

The LSC self-normalization and calibration protocol (SNC) was executed prior to counting wipe samples to normalize the LSC and to establish 3H and 14C detection efficiency. Sample one was utilized as the control and counted for 10 minutes. The control result was automatically subtracted from wipe sample results. The wipe samples were dissolved in 4 ml of National Diagnostics Ecoscint biodegradable scintillation cocktail and allowed to sit for three (3) hours in the dark prior to counting. Counting channel windows were established at 0 – 12 keV (3H), 12 – 156 keV (14C) and 0 - 2000 keV (open window). Such window widths recognized the cross-channel counting effect between the nuclide of interest, but at the same time cover the range of beta and gamma emissions from the authorized radionuclides. The Nuc- Wipes were allowed to completely dissolve prior to counting, thus providing an optically unquenched counting solution. The results were then compared to the screening levels for surface contamination in HPS/ANSI N13.12-2013 Table 1 – Group 2 to determine compliance.

1 Calculations performed using equation 6-6 and 6-7 in MARSSIM [2]

4 .0 SURVEY RESULTS

4.1 SURVEY RESULTS

The survey results for SU-1 were as follows:

• Radionuclide contamination distinguishable from background was not identified on fixtures, equipment and permanent building surfaces when scan-surveyed with:

o Ludlum 3 coupled to a 44-3 NaI low energy scintillation detector, o Ludlum 14C coupled to a 44-9 GM pancake detector, and o Bicron microrem survey instrument.

• All wipe samples of fixtures and equipment were less than the release criteria established in Section 2.1 of this report.

• All wipe samples of permanent building surfaces were less than the clearance criteria for permanent building surfaces presented in Section 2.2 of this report.

• The room was visually inspected for the presence of any apparent radioactive materials or tools and supplies associated with radioactive materials operations. No remaining tools, materials or supplies were identified.

The following supporting elements are attached as appendices:

• Appendix A – Survey Unit Schematic Diagrams

• Appendix B – FSS Survey Data

• Appendix C – Fixtures & Equipment Release Survey Data

• Appendix D – Wipe Sample counting data

• Appendix E – Calibration Certificates

• Appendix F – Survey Photographs

4.2 SUMMARY AND CONCLUSION

No evidence surface contamination exceeding the release criteria on fixtures and equipment or permanent building surfaces was identified. It is concluded that Room 413E, in its entirety, can be released from radiological controls and repurposed for unrestricted use.

4.3 RELEASE AUTHORITY

Room 413E contained specifically licensed radioactive materials, thus the NRC should be petitioned to release for unrestricted use.

5 .0 FINAL STATUS SURVEY REPORT APPROVAL

This Survey Plan has been reviewed and approved by:

Joseph Skovron, MBA Radiation Safety Officer

WN-L0167-1 (NRS)

Louie Cueva, RRPT Health Physicist

WN-L0167-1 (NRS)

6 .0 REFERENCES

[1] ANSI/HPS, "N13.12-2013 Surface and Volume Radioactivity Standards for Clearance," Health Physics Society, McLean, VA, 2013.

[2] US EPA, "Multi-Agency Radiation Survey and Site Investigation Manual (Revision 1)," Nuclear Regulatory Commission NUREG-1575 Rev. 1, 2000.

APPENDIX A – SURVEY UNIT SCHEMATIC DIAGRAMS

Figure 2- Lab Floor Plan

Survey Unit 1

Figure 3 - Survey Unit Boundary Designation

APPENDIX B – FSS SURVEY DATA

APPENDIX C – FIXTURES & EQUIPMENT RELEASE SURVEY DATA

APPENDIX D – WIPE SAMPLE COUNTING DATA

APPENDIX E – CALIBRATION CERTIFICATES

APPENDIX F – SURVEY PHOTOGRAPHS