Text

Texas A&M Univ. - Final Status Survey Report Supplemental Information for the Zachry Engineering Center
	ML17010A057
Person / Time
Site:	Texas A&M University
Issue date:	01/09/2017
From:	Mcdeavitt S; Texas A&M Univ
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	2017-0001
	Download: ML17010A057 (61)
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NUCLEAR SCIENCE CENTER Dr. Sean M. McDeavitt Director, TEES Nuclear Science Center Texas A&M University Texas A&M Engineering Experiment Station 1095 Nuclear Science Road, 3575 TAMU College Station, TX 77843-3575 January 9, 2017 2017-0001 Docket Number 50-59 / License No. R-23 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Ref: 10 CFR 50.90

SUBJECT:

Final Status Survey Report Supplemental Information for the Zachry Engineering Center Attn: Mr. Alexander Adams Jr., Chief, Research and Test Reactors Branch Office of Nuclear Reactor Regulation Mr. Patrick M. Boyle, Project Manager, Research and Test Reactors Branch Office of Nuclear Reactor Regulation By letter dated November 21, 2016 (ADAMS Accession No. ML16326A447), as supplemented by two letters dated December 16, 2016 (ADAMS Accession Nos. ML16351A502 and ML16352A00),

Texas A&M University (TAMU) s u b m i t t e d a license amendment request (LAR) to Operating License No. R-23, Docket 50-59, seeking U.S. Nuclear Regulatory Commission (U.S. NRC) approval for the unrestricted release of the Zachry Engineering Center located on the TAMU Campus. The approval of this LAR will result in the removal of the Zachry Engineering Center site from the R-23 license.

During a phone call on January 9, 2017, the U.S. NRC staff requested additional information be added to the Final Status Survey (FSS) report. Specifically, the U.S. NRC requested additional detector data be added to Table A-1 in the FSS report. In addition, the U.S. NRC staff requested that the static measurements summary and related survey information be included in the FSS. These actions have been completed. Enclosure 1 contains the FSS with the required additional information.

Should you have any questions regarding the LAR, please contact me or Mr. Jerry Newhouse at (979) 845-7551 or via email at mcdeavitt@tamu.edu or newhouse@tamu.edu.

Nuclear Science Center 1095 Nuclear Science Road, 3575 TAMU 1 College Station, TX 77843-3575 Tel. (979) 845-7551

NUCLEAR SCIENCE CENTER Oath of Affirmation I declare under penalty of perjury that the foregoing is true and correct to the best of my knowledge.

Sincerely, Sean M. McDeavitt, PhD Director, TEES Nuclear Science Center Submitted with Level 2 Delegate Authorization from Dr. Yassin Hassan in letter dated February 8, 2016 (ADAMS Accession No. ML16043A048) : Final Status Survey Summary Results Updated for the Unrestricted Release of the Zachry Engineering Center CC: next page Nuclear Science Center 1095 Nuclear Science Road, 3575 TAMU 2 College Station, TX 77843-3575 Tel. (979) 845-7551

NUCLEAR SCIENCE CENTER cc:

William Dean, Office Director United States Nuclear Reactor Commission Office of Nuclear Reactor Regulation Michael Young, President Texas A&M University 1246 TAMU College Station, TX 77843-1246 Dr. M. Katherine Banks, Vice Chancellor and Dean Dwight Look College of Engineering 3126 TAMU College Station, TX 77843-3126 Dr. Yassin Hassan, Department Head, Nuclear Engineering Texas A&M University Nuclear Engineering Department 3133 TAMU College Station, TX 77843-3133 Dr. John Hardy Reactor Safety Board Chairman Texas A&M University 3255 TAMU College Station, TX 77843-3255 Dr. Latha Vasudevan Radiological Safety Officer, Texas A&M University Environmental Health and Safety 1111 Research Parkway College Station, TX 77843-4472 Jerry Newhouse NSC Assistant Director Texas A&M Engineering Experiment Station 3575 TAMU College Station, TX 77843-3575 Scott Miller NSC Manager of Reactor Operations Texas A&M Engineering Experiment Station 3575 TAMU College Station, TX 77843-3575 Jeremy Osborn AGN-201M Reactor Supervisor Texas A&M University Nuclear Engineering Department 3133 TAMU College Station, TX 77843-3133 Nuclear Science Center 1095 Nuclear Science Road, 3575 TAMU 3 College Station, TX 77843-3575 Tel. (979) 845-7551

NUCLEAR SCIENCE CENTER ENCLOSURE 1 TEXAS A&M UNIVERSITY FACILITY LICENSE R-23, DOCKET NO. 50-59 OPERATING LICENSE AGN-201M REACTOR UPDATED FINAL STATUS SURVEY RESULTS Nuclear Science Center 1095 Nuclear Science Road, 3575 TAMU 4 College Station, TX 77843-3575 Tel. (979) 845-7551

FINAL STATUS SURVEY REPORT:

ZACHRY ENGINEERING CENTER AGN201M REACTOR AREAS TEXAS A&M UNIVERSITY COLLEGE STATION, TEXAS Updated January 9, 2017 Prepared by:

ReNuke Services, Inc.

710 S. Illinois Ave., Suite F104 Oak Ridge, Tennessee 37830 Prepared By January 9, 2017 ReNuke Services Date

Contents 1.0 EXECUTIVE

SUMMARY

.................................................................................................... 2

2.0 INTRODUCTION

............................................................................................................... 2 3.0 PURPOSE AND SCOPE ...................................................................................................... 2 4.0 SITE DESCRIPTION ........................................................................................................... 3 5.0 RADIOLOGICAL CONTAMINANTS AND CRITERIA .......................................................... 6 6.0 IMPACTED AREAS AND SURVEY UNITS .................................................................................. 10 7.0 SURVEY APPROACH ................................................................................................................ 11 7.1 General .................................................................................................................. 11 7.2 Site Preparation....................................................................................................... 11 7.3 Integrated Survey Strategy ..................................................................................... 11 7.4 Survey Instrumentation .......................................................................................... 11 7.5 Surface Scans ......................................................................................................... 14 7.6 Static Surface Activity Measurements ................................................................... 14 7.7 Removable Contamination Measurements .......................................................... 15 7.8 Samples and Analyses ........................................................................................... 15 7.9 Quality Assurance/Quality Control ......................................................................... 15 7.10 Data Evaluation ...................................................................................................... 15 8.0 SURVEY UNITS .............................................................................................................. 16 9.0 ISOLATION AND CONTROL...22 10.0 REPORT....22

11.0 REFERENCES

............................................................................................................... . 22 APPENDIX A - MEASUREMENT & DETECTION SENSITIVITIES .................................................A1 APPENDIX B - GRID LAYOUTS (FIELD DRAWINGS) .................................................................. B1 APPENDIX C - FSS STATIC MEASUREMENTS AND HEALTH PHYSICS DATA

SUMMARY

.C1

ACRONYMS AND ABBREVIATIONS ALARA As Low As is Reasonably Achievable C carbon cm centimeter cm2 square centimeter cpm counts per minute Cs cesium dpm disintegrations per minute Eu europium 3

H tritium hr hour keV kiloelectron volt m meter m2 square meter MARSSIM MultiAgency Radiation Survey and Site Investigation MDC minimum detectable concentration MDCR minimum detectable count rate MeV million electron volts pCi picocurie pCi/g picocurie per gram PuBe plutoniumberyllium (neutron source)

RSSI Radiation Site Survey and Investigation TAMU Texas A&M University TDSHS Texas Department of State Health Services U uranium U.S. NRC United States Nuclear Regulatory Commission Ci microcurie 1

FINAL STATUS SURVEY REPORT ZACHRY ENGINEERING CENTER AGN201M RESEARCH REACTOR FACILITY TEXAS A&M UNIVERSITY, COLLEGE STATION, TX 1.0 EXECUTIVE

SUMMARY

As part of the TAMU renovation and expansion of the Zachry Engineering Center, the AGN201M reactor (U.S. NRC Facility License R23) has been defueled, packaged and placed in secure offsite storage, and is awaiting reinstallation in a new facility. The Part 50 license of record (R23) is not being terminated but has been amended to reflect the current storage arrangements. Associated materials and equipment previously in the reactor facility have been surveyed, removed, and dispositioned in accordance with the TAMU release criteria. Extensive radiological surveys have been conducted in accordance with a Final Status Survey Plan, revised in document dated November 10, 2016 (ADAMs Accession Number ML16316A002). No radioactive surface contamination has been identified and no neutron activation of the building structures has been detected; a summary of survey and sampling data is presented in section 5, Radiological Contaminants and Criteria. Based upon the survey results relative to the 60Co screening values selected for the project, TAMU concludes the former reactor areas of the Zachry Engineering Center meet the applicable release criteria presented in Subpart E to 10 CFR 20, Criteria for License Termination, and requests unrestricted release of these areas from License R23 controls.

2.0 INTRODUCTION

Extensive alpha and beta surface contamination surveys were conducted using gas proportional detectors and swipes were collected and evaluated, all in accordance with the FSS Plan. No contamination over background was detected. Concrete samples from shield blocks previously positioned around the reactor support skirt, from walls in the reactor room, and from the floor directly under the reactor were collected and submitted for analyses by an offsite laboratory to confirm no neutron activation products are present at levels of consequence. No activation products have been detected, with minimum detectable concentrations all less than 10% of the NUREG 1757 (Ref 1) screening values developed for soil contamination. The soil screening values were directly applicable, as demolition of a block wall was necessary for removal of the reactor shield tank.

3.0 PURPOSE AND SCOPE The purpose of the release surveys is to demonstrate that areas of the Texas A&M University Zachry Engineering Center that previously housed the AGN201M reactor and associated facilities satisfy criteria of the Nuclear Regulatory Commission, Texas Department of State Health Services, and Texas A&M University Radiological Safety, Environmental Health and Safety for unrestricted release. By satisfying these criteria, the remaining structure can be demolished or reused without radiological restrictions.

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TAMU has used the Screening Limits for 60Co, as published in NUREG 1757, Volume 2, Consolidated Decommissioning Guidance, as upper limits for the project to comply with the requirements of 10 CFR 20.1402, radiological criteria for the unrestricted release. In accordance with this rule, the site is considered acceptable for unrestricted use if the residual radioactivity that is distinguishable from background radiation results in a total effective dose equivalent (TEDE) to an average member of the public that does not exceed 25 mrem (0.25 mSv) per year. No contamination has been detected on any surfaces or components during extensive Final Status Surveys. These results are consistent with surveys conducted in support of defueling and during earlier scoping surveys.

Site characteristics support the use of these values, as only superficial surface contamination was deemed to be potentially present. In addition, there are no buried pipes or potentially contaminated structures, and no unusual radionuclides have been identified or considered likely. The screening values have been determined by the U.S. NRC to be ALARA; no further pathways evaluations are required (Appendix N to NUREG - 1757, Volume 2). TAMUs selfimposed release criteria are more limiting (contamination is not to exceed twice background, using appropriate instrumentation), as explained below.

4.0 SITE DESCRIPTION Figure 1 is a site map of the Texas A&M campus, indicating the location of the Zachry Engineering Center on Bizzell Street near University Drive. The AGN201M reactor (Fig. 2) was designed and installed as a fully selfcontained unit, with no external coolant or sample irradiation systems. It was located in Room 61B on the ground floor, in the southwest portion of the building (Fig. 3). The maximum authorized steady state operating power level for the reactor is 5 watts. The reactor did not operate for several years prior to defueling and removal from the building. The design of the AGN201M reactor precluded the possibility of groundwater or soil contamination, as there are no external coolant pumps, heat exchangers, coolant makeup/cleanup systems, or no external irradiation loops. In addition, the basic design eliminates the need for radioactive waste processing systems (e.g., no waste compaction, liquid waste treatment, or contaminated off gas treatment systems). Accordingly, the FSS Plan did not address soil or groundwater sampling.

Room 60C was primarily used for office space and access control. Room 61A was used in support of reactor operations (e.g., safeguards laboratory work, experiment preparation). Room 61B contained the reactor control console and a small inner room where radioactive sources were stored. Access to the top of the reactor was through Room 135 (Fig. 4) on the 1st floor level, directly above the reactor room. Rooms 60C, 61A, 61B, and room 135 (which previously contained three ion accelerators) constitute the primary site security boundaries for the reactor. Figures 3 and 4 show the layouts of the reactor facility; bolded outlines indicate Primary Reactor Site boundaries.

During normal power operation, ventilation for the reactor area was provided by a ventilation fan that pulled air through a grated opening in the Room 61B ceiling and into Room 135. Portions of the ventilation system duct external to the reactor facility were surveyed in early 2016 during laboratory facility surveys, and found to meet the applicable release criteria.

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Figure 1. Map of Texas A&M Campus, indicating location of Zachry Engineering 4

Figure 2. Cutaway View (left) and photo (right) of AGN201M Reactor

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48 --------------------

High density interior block walls Figure 3 Reactor Facility Ground Floor; Bolded outline indicates Security Boundary and areas subject to Final Status Surveys Sampled exterior block wall 5

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48 ---------------------------

Figure 4. Reactor Facility First Floor; Bolded outline indicates primary Security Boundary and areas subject to Final Status Surveys 5.0 RADIONUCLIDE CONTAMINANTS AND CRITERIA AGN201M reactor operations in the Zachry Engineering Center began in 1972 and concluded in 2014.

Records and anecdotal information from the former Senior Reactor Operator have not revealed any reactor incidents or occurrences which may have resulted in contamination of surfaces external to the reactor shield tank. Surveys performed by the TAMU Radiological Safety staff did not identify any detectable removable contamination on reactor components or reactor room surfaces. Recent scoping surveys did not detect any fixed or removable contamination on surfaces in potentially impacted rooms. Considering the low power level and limited operating time, the low neutron fluence rate, inherent shielding provided by the reactor components and containment tank, and the decay time since last operation, the likelihood of detectable activity in facility structural media was considered negligible.

Conservative bounding calculations estimate 152Eu (likely the predominant activation product in concrete) specific activity in the range of 103 pCi/g in concrete shield blocks that were located around the reactor support skirt. Sampling and analyses were conducted to validate the calculationbased conclusion that no activation products are present at detectable levels. Candidate radionuclides for concrete activation include 152Eu, 154Eu, 60Co, 134Cs, 3H, and 14C. Laboratory analyses (gamma spectrometry and liquid scintillation counting) of samples are summarized in Table 1. Samples included cores from four innermost shield blocks from the reactor skirt, one core from the reactor room wall across from the north glory hole (a reactor opening), Three cores from the south block wall in line with 6

Table 1. Volumetric Sample Data (Samples were analyzed by General Engineering Laboratories of Charleston, S.C.)

134Cs, pCi/g 60Co, pCi/g 152Eu, pCi/g 154Eu, pCi/g 3H, pCi/g 14C, pCi/g Result MDC Result MDC Result MDC Result MDC Result MDC Result MDC (uncertainty) (uncertainty) (uncertainty) (uncertainty) (uncertainty) (uncertainty)

Wall: hallway (no neutron irrad.) 2.17E02 9.05E03 8.93E04 5.03E02 4.54E01 3.5E01 (3.05E02) 5.82E02 (4.07E02) 7.23E02 (6.84E02) 1.12E01 (8.19E02) 1.73E01 (3.08) 5.43E+00 (8.15E01) 1.41E+00 Wall: N side, opp glory hole 1.58E02 5.32E03 8.47E02 7.42E02 2.24 4.78E01 8.97E02 9.91E02 1.90E01 2.97E01 5.44E+00 1.37E+00 (4.87E02) (5.28E02) (1.28E01) (1.54E01) (3.01) (7.88E01)

S. Wall 1: IW1 (wall removed) 5.74E04 6.36E03 1.44E02 1.65E02 2.11 3.68E01 (2.75E02) 4.77E02 (2.22E02) 4.30E02 (5.56E02) 1.09E01 (5.1E02 1.01E01 (4.23) 7.63E+00 (3.73E01) 6.26E01 S. Wall 2: IW2 (wall removed) 2.84E03 1.24E03 1.2E02 5.85E02 1.58 1.33E01 4.52E02 4.11E02 1.40E01 1.30E01 7.85E+00 6.01E01 (2.03E02) (1.62E02) (7.1E02) (7.39E02) (4.38) (3.54E01)

S. Wall 3: IW3 (wall removed) 3.0E02 1.83E03 4.68E02 7.18E02 3.10E01 4.62E01 7.01E02 6.72E02 1.29E01 2.26E01 8.08E+00 6.21E01 (3.15E02) (3.19E02) (7.23E02) (9.79E02) 4.61 (3.72E1)

Reactor shield block: E1 2.91E02 3.16E03 4.82E02 2.03E03 2.26E01 1.38E01 7.87E02 7.69E02 1.31E01 2.17E01 7.96E+00 5.98E01 (3.84E02) (3.94E02) (7.42E02) (1.09E01) (4.52) (3.53E01)

Reactor shield block: S1 2.98E03 9.55E04 2.08E02 2.81E02 8.24E01 4.06E01 8.06E02 7.64E02 1.70E01 1.86E01 8.07E+00 6.14E01 (4.15E02) (3.54E02) (9.69E02) (8.95E02) (4.63) (3.67E01)

Reactor shield block: N1 7.06E03 3.98E04 1.16E01 2.8E02 2.78 3.01E01 5.54E02 7.87E02 1.64E01 1.99E01 7.88E+00 6.07E01 (2.54E02) (4.03E02) (1.17E1) (1.09E01) (4.34) (3.61E01)

Reactor shield block: W1 2.13E03 2.61E02 4.69E03 1.65E02 9.02E01 5.79E02 6.01E02 5.80E02 1.30E01 1.84E01 8.06E+00 6.01E01 (3.17E02) (3.35E02) (6.45E02) (9.46E02) (4.54) (3.53E01)

Reactor pad concrete 1 1.01E02 4.68E03 5.15E03 2.28E02 5.41E01 3.06E01 (2.76E02) 5.89E02 (2.55E02) 5.19E02 (6.32E02) 1.26E01 (6.52E02) 1.55E01 (3.47) 6.85E+00 (3.77E01) 6.34E01 Reactor pad concrete 2 1.65E02 1.91E02 4.01E03 4.81E04 4.83E01 2.25E01 (2.48E02) 5.59E02 (3.00E02 5.20E02 (5.66E02) 1.14E01 (6.63E02) 1.41E01 (2.99) 6.30E+00 (3.76E01) 6.35E01 Floor under reactor pad, 1 3.35E02 1.59E02 8.95E02 4.36E2 1.70 2.35E01 9.17E02 6.72E02 1.77E01 2.07E01 6.27E+00 6.51E01 (6.00E02) (3.61E02) (8.77E02) (8.98E2) (3.45) (3.77E01)

Floor under reactor pad, 2 4.98E03 2.55E03 5.05E03 2.99E02 1.13 3.33E01 (3.45E02) 6.87E02 (2.21E02) 5.17E02 (9.56E02) 1.69E01 (1.06E01) 1.98E01 (3.48) 6.58E+00 (3.75E01) 6.30E01 Ceiling plug 1.36E02 1.34E02 2.11E02 2.57E03 7.42E01 3.26E01 (Thermal Column) (1.95E02) 4.95E02 5.28E02 (5.93E02) 1.16E01 1.30E01 6.71E+00 6.40E01 (1.89E02) (5.57E02) (3.46) (3.81E01)

Table 1 Notes:

Values are presented in units of pCi/g for each radionuclide, for each sample, and are the lowest values distinguishable from background with a 95%

certainty of detection.

Minimum detectable concentrations for each of the radionuclides of interest are less than 10% of the NUREG 1757 soil screening values. Europium MDCs were also < 10% of the EPA limiting values for residential soils.

The soil screening values are directly applicable to the project, as the south wall of room 61B was demolished to remove the reactor tank.

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the glory hole (this was was later demolished), two cores from the concrete reactor pad, two cores from the concrete floor directly under the reactor pad, one core from the overhead concrete shield plug, and one core from the wall in the access hallway, an area with no significant neutron exposure.

None of the samples were found to contain detectable activation products.

Coverings have not been applied over any known location of contamination. Based upon documented neutron dose rates (as incorporated in facility Safety Analysis Report), the location in the facility considered most likely to have been impacted by reactor operations is the concrete floor directly beneath the reactor shield tank. Radionuclides in the above table dominate the potential source term, and there is no history of contamination by other radionuclides on surfaces external to the reactor.

Section 17.1.4 of NUREG1537 establishes the following criteria to release nonpower reactor facilities for unrestricted use

1. a) no more than 5 microrem per hour above background at 1 m from the surface measured for indoor gamma radiation fields from concrete, components, and structures, or b) no more than 10 millirem per year for gamma emitters above background absorbed dose to any person, considering reasonable occupancy and proximity (U.S. NRC letters dated March 17, 1981 and April 21, 1982).

2. Residual surface contamination consistent with Regulatory Guide 1.86.

Regulatory Guide 1.86 was withdrawn by U.S. NRC, effective August 12, 2016, however the table of acceptable surface contamination values has been retained (see Table 2) for the project as these values are also in Texas Regulation 25 TAC §289.202(ggg)(6), Acceptable surface contamination levels (Ref 2), and are applicable to Statelicensed activities at TAMU.

Table 2. Acceptable Surface Contamination Levels a

Nuclide Total Removable Unat, U235, U238, and associated decay products 5000 dpm/100 cm2 1000 dpm/100 cm2 Transuranics, Ra226, Ra228, Th230, Pa231, Ac 100 dpm/100 cm2 20 dpm/100 cm2 227, I125, I129 Thnat, Th232, Sr90, Ra223, Ra224, U232, I126, 1000 dpm/100 cm2 200 dpm/100 cm2 I 131, I133 Betagamma emitters (nuclides with decay 5000 dpm/100 cm2 1000 dpm/100 cm2 modes other than alpha emission or spontaneous fission) except Sr90 and others noted above

a. Where surface contamination by both alpha and betagamma emitting radionuclides exist, the limits established for alpha and betagammaemitting radionuclides apply independently.

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The TAMU radiation safety program has a policy of no detectable activity for unrestricted use and release. No detectable activity is interpreted by TAMU as not exceeding twice the background level (Ref 3).

No materialsspecific background count rates were subtracted during scanning surveys of facility surfaces; ambient background counting rates were used. Note that 2step surveys were used for static measurements, as described in section 7.3, Integrated Survey Strategy.

The nominal ambient background values were used to calculate the sensitivity of the scanning surveys to ensure they are adequate relative to the surface contamination Screening Values presented NUREG 1757, Appendix H. Because no residual radioactivity was identified during extensive surveys of the reactor, associated components, and the facility, no specific radionuclides of interest could be identified. The NUREG 1757, Appendix H surface contamination screening value for 60Co (7,100 dpm/100 cm2) was conservatively chosen for evaluation of potential building contamination. Table 3 presents a summary of the minimum detectable surface contamination, the U.S. NRC screening value, and the surface contamination levels corresponding to twice the background levels (the TAMU constraint).

During scanning surveys, net count rates exceeding 450 cpm beta were used as scanning limits when using the 126 cm2 detectors, or 800 cpm beta for the 580 cm2 detector (i.e., contamination exceeding the screening value for 60Co). No instances of elevated scanning count rates were observed.

Gross activity surveys limits were applied (i.e., not to exceed twice background, alpha and betagamma activity evaluated independently). Also, note that net count rates exceeding 3 cpm alpha or 250 cpm beta when using the 126 cm2 detectors, or 9 cpm alpha or 300 cpm beta for the 580 cm2 detector, were established as limits indicative of contamination exceeding the TAMU criteria (twice background). No individual FSS measurements exceeded these threshold values and no remedial action was required.

Table 3 - Summary data Detector/Application MDA U.S. NRC Co60 TAMU twice (dpm/100 cm2) Default Screening background Value equivalent (dpm/100 cm2) (net dpm/100 cm2) 126 cm2 gas Alpha N/A

Alpha N/A* N/A proportional/scan 1500 beta 7100 3000 126 cm2 gas 63 alpha Alpha N/A* 26 alpha (< MDC) proportional/static 470 beta 7100 2200 beta 580 cm2 gas Alpha N/A* Alpha N/A* A > 2 x background proportional/scan 2280 beta 7100 reading will be (for a 100 cm2 spot) investigated with a 126 cm2 detector Laboratory 19 alpha Alpha N/A* 4 alpha counter/removable activity 90 beta 710 500 beta

No potential alphaemitting contaminants have been identified 9

Measured background exposure rates within the Zachry Engineering Center are 5 to 8 microR/hr. Surveys confirmed that dose rates from background plus residual licensed material are no more than 10 microR/h, measured at 1 m from building surfaces, confirm compliance with the TAMU less than twice background criterion. The observed dose rates are also consistent with the previously noted guidance from NUREG 1537.

6.0 IMPACTED AREAS AND SURVEY UNITS The MARSSIM (Ref 4) defines impacted areas as those with a possibility of residual radioactivity in excess of background levels. Radiological surveys of impacted areas are required to demonstrate that established criteria have been satisfied. Nonimpacted areas are those with no reasonable expectation of residual contamination; no surveys of nonimpacted areas are required. Impacted areas are classified as to contamination potential as follows:

Class 1: Areas that have, or had prior to remediation, a potential for radioactive contamination (based on site operating history) or known contamination (based on radiological surveys) expected to be in excess of established unrestricted release criteria.

Class 2: Areas that have, or had prior to remediation, a potential for radioactive contamination or known contamination, but are not expected to exceed established criteria.

Class 3: Areas that are potentially impacted but are not expected to contain any residual radioactivity, or are expected to contain levels of residual activity at a small fraction of the established criteria, based on site operating history and previous radiological surveys.

Table 4 presents the AGN201M reactor facility impacted areas and survey units. Categorization was based on use history, previous monitoring records, and screening surveys conducted during removal of furnishings, materials, and equipment from the facility.

Table 4 Impacted Areas and Survey Units Class Level Room(s) Surfaces Number of Survey Units Class 1 Ground 61A Floor and lower walls 1 Ground 61B Floor and lower walls 1 First 135 Floor and lower walls 2 Class 2 Ground 61A and 61B Upper walls and ceiling 1 Class 2 First 135 Upper walls and ceiling 1 Class 3 Ground 60C All 1 10

7.0 SURVEY APPROACH 7.1 General A survey plan was prepared in accordance with guidelines and recommendations, presented in the Multi Agency Radiation Survey and Site Investigation Manual (Ref 4). The process described in this reference emphasizes and incorporates the use of Data Quality Objectives and Data Quality Assessment, along with a quality assurance/quality control program. A graded approach was implemented to assure that survey efforts were maximized in those areas having the greatest potential for residual contamination or the highest potential for adverse impacts of residual contamination.

Trained and qualified radiological technicians conducted field measurements, following standard procedures and using calibrated instruments appropriate for detecting and measuring the potential contaminant.

7.2 Site Preparation Furnishings, materials and equipment were removed from the facility in accordance with TAMU Radiation Safety Program procedures. Following disassembly, defueling, removal and transfer of the reactor and associated components, drains, ducts, grates, cable trays, etc., were accessed and surveyed.

Nominal 100 cm2 dual phosphor detectors (Ludlum Instruments Model 4393) have been used with dual channel scaler/ratemeters (Ludlum Instruments Model 2360) for health physics surveys conducted in support of defueling and cleanup work. Background and efficiencies for these scintillation detectors are identical to the gas flow proportional detectors selected for final status surveys. Use of the model 4393 scintillation detectors was augmented with thinwindow pancake GeigerMueller detectors with scaler/ratemeters (Ludlum Instruments Model 439 detectors with Model 3 scaler/ratemeters) to access smaller diameter penetrations (e.g., used for electric cables, water supply lines, natural gas lines, etc.).

No detectable residual activity was identified on building surfaces, with MDCs well below the U.S. NRC and TAMU release criteria as presented in Table 2 and no remediation was required. Building surfaces were appropriately gridded at 1 m intervals, as practical for the conditions. Grid origins are located in the southwest corner of each survey unit.

7.3 Integrated Survey Strategy Radiological surveys consisted of:

Surface scans for elevated levels of gross alpha, beta, and gamma radiation levels, Static measurements of gross alpha and gross beta activity, Smears for removable gross alpha and gross beta activity, and Sampling for laboratory analysis of specific radionuclide contaminants.

Table 5 indicates the survey rigor used. Facility operating history and surveys performed in support of reactor disassembly support the selected graded approach.

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Table 5. Survey Rigor for Each Survey Unit Contamination Alpha, Beta & Static Alpha and Beta Removable Survey Class Gamma Scan Alpha & Beta 1 100% all Systematic static measurement at a minimum of At each static structure 18 locations and at additional locations of measurement surfaces highest potential contamination, based on location professional judgment and scan results 2 50% floor and Systematic static measurement at a minimum of At each static lower walls; 18 locations and at additional locations of measurement 10% upper walls highest potential contamination, based on location and ceiling professional judgment and scan results surfaces 3 10 % floor and One floor measurement and 1 lower wall At each static 1 m2 around measurement per 10 m2 of floor area in each measurement each static room, and measurements and at additional location measurement locations of potential contamination, based on location on professional judgment and scan results lower walls (minimum of 18 data points per survey unit).

Because the TAMU acceptable release criterion of twice background is very low, Scenario B, as recommended by NUREG1505 (Ref 5), is the basis for the survey design. The Null Hypothesis for that Scenario is:

The survey unit meets the release criterion.

The objective of the release survey is to accept this Null Hypotheses, by demonstrating at a Type I ()

decision error level of 0.05 and a Type II () decision error level of 0.025 that residual contamination is less than twice background. Multiple building surface types (e.g., concrete, metal, glass) are present in most survey units and background levels, particularly radon daughters, exhibited variability by instrument, material, time of day, and location within the facility. To facilitate adjusting measurements for appropriate localized background contributions, a paired measurement approach was used for static measurements. To perform paired measurements, a measurement was first performed by placing a piece of nominal 1/4in metal shield material between the surface and the Ludlum 4368 detector face. The static measurement was repeated without the intervening shield material, and the difference between the second and first measurement is the net contamination measurement.

No individual static measurement identified detectable activity in excess of the project limits (e.g., all net measurements must be less than the 3 alpha and 250 beta cpm nominal count rates, as measured with the 4368 detectors the more restrictive TAMU limits). No statistical tests are required to demonstrate compliance with release criteria.

To establish the number of measurements needed to demonstrate that residual contamination criteria have been satisfied, a parameter known as the relative shift, which effectively describes the 12

distribution of final sample data, is calculated, as follows:

/ = (DCGLLBGR)/ , [1]

/ = relative shift DCGL Criteria = cleanup criteria LBGR = lower bound of the gray region and is defined in the DQOs as 50 percent of the DCGL. Where final sample data are not yet available, MARSSIM guidance (Section 5.5.2.2) assigns a value of onehalf of the DCGL for the LBGR.

= standard deviation of the sample concentrations in the survey unit.

Where final sample data are not yet available, MARSSIM guidance (Section 5.5.2.2) recommends a value of 30 percent of the DCGL.

Using the equation for relative shift and MARSSIM guidance for situations where final sample data are not yet available, the relative shift for design purposes is (1 - 0.5)/0.3 for a value of 1.67. Based on the relative shift of 1.67 and Type I and Type II decision errors of 0.05 and 0.025, respectively, the number of required data points from each survey unit to perform the evaluation, as obtained from MARSSIM guidance (Table 5.5) is 18.

For static measurement locations on Class 1 and Class 2 room surfaces, a random start point was identified on the floor and additional measurement locations were systematically selected on a triangular spacing from that start point. Spacing distance, L, was determined by:

L= [(Survey Unit Area)/0.866 x number of data points]0.5 [2]

Ductwork and piping was removed, or internals were accessed, scanned, and static measurements performed at the open ends and additional points at a frequency of 1 measurement/4 m2 of internal surface area.

Static measurement locations in Room 60C, the only Class 3 unit, were at locations of highest contamination potential, based upon area uses and as selected by professional judgment.

Appendix B presents the grid layout field drawings for each survey unit, derived as described above.

7.4 FSS Survey Instrumentation Table 6 is a list of radiological survey instrumentation used for the AGN201M reactor facility surveys.

These instruments are maintained, calibrated, and operated in accordance with written procedures. For application to unrestricted release, instrument response (efficiency) is based on NIST-traceable sources of 99Tc (beta EMAX = 292 keV) and 230Th (alpha E = 4.68 MeV). The energies of these radionuclides are 13

representative of the dominant potential contaminants. Note that the 126 cm2 4368 gas flow proportional detectors have efficiencies and ambient background count rates that are identical to the 100 cm2 4393 dual phosphor scintillation detectors used for health physics surveys during facility preparations for release; survey data are directly comparable.

Table 6. Instrumentation for Final Status Surveys Detector Display Application Ludlum 4337 Ludlum 2360 Alpha /beta scans Ludlum 4368 Ludlum 2360 Alpha/beta scans Ludlum 4368 Ludlum 2360 Alpha/beta static measurements Ludlum 4310 Ludlum 2929 Removable alpha/beta measurements (scaler)

Ludlum 19 N/A Gamma scans/direct gamma measurements For field measurement applications, calibration represents 2 response. Effects of surface conditions on measurements are integrated into the overall instrument response through use of a source efficiency factor, in accordance with the guidance in ISO75031 (Ref 6) and NUREG/CR1507 (Ref 7). Default surface efficiencies of 0.25 for alpha emitters and 0.25 for beta emitters will be used.

Detection sensitivities are estimated using the guidance in MARSSIM and NUREG/CR1507.

Instrumentation and survey techniques are chosen with the objective of achieving detection sensitivities of <50% of the criteria for structure surfaces, for both scanning and direct measurement. These detection sensitivities assure identification of areas potentially exceeding the established project criteria.

Minimum detectable activity levels are adequate for the project. Refer to Appendix A for derivation of applicable MDAs 7.5 Surface Scans Handheld Ludlum Model 4368 gas proportional detectors (126 cm2) used with Ludlum Model 2360 scaler/ratemeters were used for alpha and beta surface scanning to identify locations of potential residual surface. A largearea cartmounted Ludlum Model 4337 gas proportional detector (580 cm2) was used with a Ludlum Model 2360 scaler/ratemeter to scan the floor surfaces. The smaller handheld detector was also used to survey floor areas not accessible with the larger detector. Alpha/beta scanning was performed by maintaining the detector within 1/4in of the surface and moving the detector over the surface at a rate of approximately half of the detector width per second, while monitoring the audible output of the scaler/ratemeter for immediate identification of increases in count rate. When 2 alpha counts are detected within approximately 2 s, the detector movement was halted at the location for approximately 10 seconds to detect a possible elevated count rate. This is consistent with Appendix J guidance in the MARSSIM document (NUREG 1575).

Ambient background levels were used during scanning surveys of the floors and the remainder of the facility surfaces (primarily poured concrete walls, steel and glass). No materialsspecific background count rates were subtracted from scanning surveys of facility surfaces.

14

A Ludlum Model 19 MicroR gamma survey instrument was used for gamma scans. General area gamma monitoring was performed with the instrument approximately 1 m above the floor.

7.6 Static Surface Activity Measurements Static measurements of alpha and beta surface activity were performed using the Ludlum Model 4368 gas proportional detectors with Ludlum Model 2360 scaler/ratemeters. Measurements were conducted by holding the detector in position within 1/4in of the surface and integrating the count over a 2min period. Two measurements, one shielded and one unshielded, were performed at each static measurement location, with the net count rate being the difference between the two measurements, for alpha and beta detection.

7.7 Removable Contamination Surveys A smear for removable activity was performed at each static surface activity measurement location. A 100 cm² surface area was wiped with a nominal 2 in diameter cloth smear, using moderate pressure.

7.8 Swipe Sample Analyses Smears were analyzed onsite for gross alpha and gross beta activity by performing 2minute integrated counts using a Ludlum Model 2929 scaler with a Model 43101 dual scintillation detector (or equivalent instrumentation).

7.9 Quality Assurance/Quality Control Measurements were performed in accordance with the survey plan by qualified personnel following written instrument operating procedures. Instrument calibration practices meet ANSI standards and daily background and source response checks of instruments were performed to verify consistent acceptable operation. For quality control purposes, replicate static and removable activity measurements were obtained at 2 locations in each survey unit.

A Radiochemistry Technical Case Narrative was provided by the laboratory for each sample set, and included a Data Summary and Quality Control Information related to analytical work performed. The analytical data reports were reviewed and accepted.

7.10 Data Evaluation Surface contamination measurement data was adjusted for ambient background and converted to units of net counts per minute. Data was assessed during collection and during survey reviews to verify consistency with the survey plan and design assumptions. Individual data points have been compared with the count rate limit derived from NUREG 1757 surface contamination screening values for 60Co and the TAMU criteria of twice background - no survey points failed. Because each survey point individually passed the acceptance criteria, no statistical evaluation of the data set is required.

15

Evaluation of volumetric sample data has been presented in Section 4, Radionuclide Contaminants and Criteria. No activation products were detected in the building structure.

Because all of the individual survey points meet the conservatively selected 60Co surface contamination screening values, and with no activation products detected, TAMU finds that Rooms 60C, 61A, 61B, and 135 meet conditions necessary for unrestricted release from license controls. The anticipated TEDE to an average member of the critical group does not exceed 25 mrem per year, as determined in the derivation of the NUREG 1757 screening values, and consistent with 10 CFR 20, Subpart E criteria for termination of license controls. In addition, with MDCs for principal concrete activation product all < 10% of the screening values, the 10 mrem/year limit in NUREG 1537 is also met with no further analyses needed (the resultant dose will not exceed 3 mrem/y, with a 95% confidence).

8.0 SURVEY UNITS A summary description and review of each survey unit follows.

8.1 Room 61B, Reactor Room Room 61B (Fig. 5) is a Class 1 survey unit that previously housed the AGN201M reactor, the associated control console, and a small source storage room. This is a nominal 66 m2 Class 1 survey unit comprised of the floor and walls up to 8 feet above the floor. A minimum of 18 static measurement and swipes were required, as derived using the methodology described in section 7.3, Integrated Survey Strategy; 23 static measurement and swipe locations were used. All floor and wall scans were less than twice background and within the 60Co screening values, as were the associated static measurements and swipes. Measured radiation levels were within background levels of 3 to 5 microR/h.

Figure 5. Room 61B, reactor room after everything was removed, cleanued up and the wall resealed.

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No reactor process piping or duct work was present in the area, as the AGN201M is a selfcontained device with no external sample irradiation or cooling piping systems.

Two electrical conduits (4in and 6in ID) are present in the floor and terminated in sealed connection boxes and run to the adjacent room (61A). These were used for reactor control wiring when the reactor control console was located outside room 61B, but have not been used in the recent past. The termination boxes were opened and surveyed, with no detectable surface contamination in excess of background identified. Each end of the conduit was directly monitored for surface contamination, with no detectable surface contamination in excess of background identified. Largearea swipes were pulled through the length of each of the two conduits and the cloth was surveyed; no detectable contamination in excess of background was identified.

A floor drain in the reactor room is located adjacent to the reactor pad and was piped to a dedicated polyethylene collection tank. This was a contingency for collection of the chromated water used for shielding in the AGN201M outer shield tank. The system was never used. As part of the facility disassembly work, the nominal 4in PVC drain line was cut into short sections and the plastic tank was sectioned to facilitate confirmation contamination surveys. No contamination over background levels was detected on the pipe sections or the tank. The floor drain grill was removed and the drain bowl surveyed in place. As with the associated piping and collection tank, no contamination over background was identified.

The former source storage area included three source storage wells (Fig. 6), constructed using nominal 9 inside diameter iron sleeves embedded approximately 4 ft in the concrete floor. The diameter was sufficiently large to permit surveys with the handheld gas proportional detectors. Direct measurements of sides and bottom were made and swipes were obtained; no detectable contamination in excess of background was identified.

Figure 6. Source storage wells.

A grate in the ceiling over the reactor shield tank provided the only airflow pathway from the room. This was not a ducted exhaust, but discharged into room 135 (the former accelerator room) through a grate in the room 135 floor. The walls of this penetration were thoroughly surveyed; no detectable contamination in excess of background was identified.

A multisegment stepped shield plug is part of the ceiling of room 61B, and was thoroughly surveyed when opened for reactor disassembly. It is addressed further in the room 135 survey summary.

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As noted above, all floor and wall scans were less than twice background and within the 60Co screening values, as were the associated static measurements and swipes. Measured radiation levels were within background levels of 3 to 5 microR/h.

8.2 Room 61A, safeguards laboratory Room 61A is a Class 1 survey unit that was previously used for preparation of reactor experiments. This is a nominal 60 m2 (including the access hallway) Class 1 survey unit comprised of the floor and walls up to 8 feet above the floor; the access hall way was included in the survey unit. A minimum of 18 static measurement and swipes were required, as derived using the methodology described in section 7.3, Integrated Survey Strategy; 20 static measurement and swipe locations were used. All floor and wall scans were less than twice background and within the 60Co screening values, as were the associated static measurements and swipes.

No reactorassociated process piping or duct work was present in the area. Two electrical conduits (4in and 6in ID) are installed in the floor and terminated in sealed connection boxes and run to the adjacent room (61B). These were used for reactor control wiring prior to the reactor control console being moved into room 61B. They have not been used in the recent past. The termination boxes were opened and surveyed, with no detectable surface contamination in excess of background identified. Each end of the conduit was directly monitored for surface contamination, with no detectable surface contamination in excess of background identified. Largearea swipes were pulled through the length of each of the two conduits and the cloth was surveyed; no detectable contamination in excess of background was identified. A short electrical conduit penetration also runs through the west wall into room 60C, the original location of the reactor console. Each end of this conduit was surveyed with handheld instrumentation and swipes were obtained from the interior surfaces, include wiring that remains present. No contamination over background levels was detected.

Radiologically unimpacted sealed cooling lines and wiring associated with former ionimplant accelerator operations ran from the overhead room 135 through a large diameter penetration in the room 61A ceiling and exited room 61A through a wall penetration. The cooling lines were removed, surveyed and confirmed to be free of detectable surface contamination. Penetrations were accessible and surveyed during the FSS work in room 135.

A chemistry bench was located in the northwest corner of room 61A (Fig. 7); it was thoroughly surveyed during scoping and characterization work, and was removed/disposed as nonradiological waste.

Utilities (natural gas, potable water, compressed air) and a glass drain line were previously connected to the bench. Following confirmatory surface contamination surveys, the utility lines were terminated and removed. The glass drain line was removed in sections along with the trap under the bench. No contamination over background was detected in the sink, the sink trap, or connection joints. Surveys included confirmatory liquid scintillation counting of samples by TAMU, with no activity (including low energy beta emitters) detected. The associated drain sump had been previously released as part of decommissioning activities associated with Statelicensed adjacent laboratories.

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All floor and wall scans were less than twice background and within the 60Co screening values, as were the associated static measurements and swipes. Measured radiation levels were within background levels of 3 to 5 microR/h.

Figure 7. Room 61A, safeguards laboratory (panoramainduced curvature).

8.3 Room 60C, access control and office area Room 60C is a Class 3 survey unit that was primarily used for controlling access to the safeguards laboratory and reactor room. It was also the initial location for the reactor control panel prior to moving it inside the reactor area. A small office for the Senior Reactor Operator was added within 60C in the late 1990s. A minimum of 18 static measurements and swipes were required, as derived using the methodology described in section 7.3, Integrated Survey Strategy; 21 static measurements and swipe locations were used. In addition to prescribed static measurements on the lower walls and floor, 100%

of the floor was scanned. Wiring penetrations in the wall from room 61A were surveyed primarily from room 61A, with confirmatory surveys performed in 60C.

A glass drain line from room 135 (the former accelerator laboratory) ran through a section of room 60C, but was not utilized in any way within 60C. The drain line was removed in its entirety as part of the scoping work for room 135; no activity was detected on the inside or outside surfaces.

All floor and wall scans were at background levels, as were the associated static measurements and swipes. Measured radiation levels were within background levels of 3 to 5 microR/h.

8.4 Room 135, accelerator laboratory Room 135 (Figs. 8 and 9) consists of two individual Class 1 survey units for floor and lower wall surveys, and a single Class 2 survey unit for the ceiling and upper walls. It was last used primarily for ionimplant accelerator experimentation. It also provided access, via heavy, stepped concrete floor plugs, to the thermal column at the top of the AGN201M reactor. Discussions with TAMU staff indicate that this access point has not been utilized since the late 1990s. In addition to the thermal column access plug, there is also a nominal 24in x 24in penetration through the floor, grated at both ends, to provide air flow from the reactor room (61B) to the accelerator room. A single point ventilation intake housing was located at the southwest corner in room 135. It was equipped with a high efficiency particulate air 19

filtration cabinet and serviced by a single blower on the roof. There was no direct connection provided for reactor operations in room 61B. The filter housing was thoroughly surveyed during early facility characterization work, but no activity was identified. The throughwall exhaust penetration in the southwest corner and the makeup air penetration in the northeast corner were thoroughly surveyed; no activity in excess of background was identified.

Figure 8. Room 135 accelerator room, looking north.

Figure 9. Room 135 accelerator room, looking south.

A chemistry bench was located in the northwest corner of room 135. It was thoroughly surveyed during scoping and characterization work, and removed/disposed as nonradiological waste. Utilities (natural gas, potable water, compressed air) and a glass drain line were previously connected to the bench.

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Following confirmatory surface contamination surveys, the utility lines were terminated and removed from their respective throughwall metal sleeves. The glass drain line was removed in sections along with the trap under the bench. The drain penetration ran through room 60C; the drain line was also removed from the ceiling of room 60C. No contamination over background was detected in the sink, the sink trap, or connection joints, or in the horizontal sections removed from 60C. Additional survey work included confirmatory liquid scintillation counting by TAMU staff of liquid samples obtained from the drain trap; no activity (including low energy beta emitters) over background detected. The associated drain sump had been previously released as part of decommissioning activities associated with State licensed adjacent laboratories. Adjacent floor penetrations allowed for routing of nonradiological accelerator cooling lines to the lower elevations. The cooling lines were removed and surveyed, along with the interior of the large floor penetration; no activity in excess of background was detected on the accelerator cooling lines or inside the penetration.

Several electrical conduit boxes are located in the southwest section of wall. Surveys inside the boxes, including swipes, did not identify activity in excess of background levels.

The building design included stepped, 4piece removable concrete shield plugs directly over the reactor to permit access to reactors thermal column (Fig. 10). The shield plug sections remained undisturbed for the last 15 years, but were removed in September as part of the reactor disassembly and defueling work. Thorough surveys were performed during the removal and prior to reassembly of the shield, and included direct and removable surface contamination measurements on the individual shield sections and the stepped lands in the floor. No activity in excess of background was identified. The bottom shield closest to the reactor was also sampled for activation products (sample ceiling plug in Table 1). No activation products were detected.

Figure 10. Shield plug details: (left) The third of four shield plugs being removed and (right) the open floor penetration above the AGN201M showing steps.

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A large, 3ton capacity overhead bridge crane was installed in the room. Surveys were conducted on the bridge and trolley steel, exposed cable on the cable drum, and on the crane hook. No activity in excess of background was identified.

A minimum of 18 static measurements and swipes were required in each Class 1 survey unit, as derived using the methodology described in section 7.3, Integrated Survey Strategy static. 18 measurement and swipe locations were used in each of the 2 Class 1 survey units. All floor and wall scans were at background levels, as were the associated static measurements and swipes.

Obtaining representative ceiling measurements was initially complicated by buildup of radon daughters on the plastic light covers (a 35 minute apparent halflife was noted when the lamps were extinguished).

Scanning and static measurements on the ceiling were subsequently performed with the associated lighting bank deenergized for an extended period prior to the start of survey work. As a conservative measure, the number of static measurements on the ceiling (a single Class 2 survey unit) was doubled from 18 to 36, effectively mimicking the floor grids (2 Class 1 survey units). Ceiling scans, static measurements, and swipes met the acceptance criteria.

In summary, all floor, wall, and ceiling scans were less than twice background and within the 60Co screening values, as were the associated static measurements and swipes. Floor shield plugs and lands were previously (October 2016) demonstrated the meet the same criteria and closed. Measured radiation levels in Room 135 were within background levels of 3 to 5 microR/h.

9.0 ISOLATION AND CONTROL Following completion of the Final Status Surveys, and the U.S. NRCdirected confirmatory surveys, the facility was locked and access controlled by TAMU pending U.S. NRC approval for unrestricted release.

These areas will not be available for general access or work until U.S. NRC approval for unrestricted release is obtained.

10.0 REPORT This report provides a survey data summary and technical justification to demonstrate acceptable conditions for unrestricted release in accordance with criteria presented in 10 CFR 20, Subpart E, Radiological criteria for unrestricted use.

11.0 REFERENCES

1. Consolidated Decommissioning Guidance Characterization, Survey, and Determination of Radiological Criteria, NUREG1757, Vol. 2, Rev. 1, U.S. Nuclear Regulatory Commission, 2006.

2. Texas Regulations for acceptable contamination levels for unrestricted use, 25 TAC§289.202(ggg)(6).

3. Radiological Safety Program Manual, Radiological Safety Environmental Health and Safety Department, Texas A&M University, July 2004.

4. MultiAgency Radiation Survey and Site Investigation Manual (MARSSIM), NUREG1575 (Rev. 1), U.S.

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Nuclear Regulatory Commission, 2000.

5. A Nonparametric Statistical Methodology for the Design and Analysis of Final Status Decommissioning Surveys, NUREG1505 (Rev 1) U.S. Nuclear Regulatory Commission, 1998.

6. Evaluation of Surface Contamination - Part 1: Beta Emitters and Alpha Emitters, ISO 75031, International Organization for Standardization, 1988.

7. Minimum Detectable Concentrations with Typical Radiation Survey Instruments for Various Contaminants and Field Conditions, NUREG/CR1507, U.S. Nuclear Regulatory Commission, 1997.

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Appendix A Measurement/Detection Sensitivities of Survey Techniques The methods for calculating survey detection sensitivities are presented in MARSSIM (Ref 4) and NUREG 1507 (Ref 7). Detector parameters used in these calculation are background count rate, efficiency (instrument response and surface correction factors), and detector area. Table A1 presents typical values of these parameters for detectors used for surveys of concrete structure surfaces of the AGN201M reactor facility. Background levels for concrete are the highest for surface media remaining in this facility, and therefore direct measurements on other media will be more sensitive than those presented here for concrete.

Table A1. Typical Detector Parameters for Site Surveys of Concrete Surfances Detector/ Background (cpm) Detector efficiency Surface correction Instrument Probe Area (cm2) alpha Beta alpha beta alpha Beta 4337 580 9 300 0.50 0.46 0.25 0.25 4368 126 3 250 0.36 0.36 0.25 0.25

4393 100 3 250 0.37 0.35 0.25 0.25 2929 N/A 1 25 0.25 0.20 N/A N/A

The 4393 detector was not used during final status surveys, but was used for health physics support surveys and during reactor disassembly. The specifications are included here to allow data to be compared with final status surveys. MDCs are comparable to the 4368 gas flow proportional detectors.

Alpha Scans Surface scans for alpha activity are conducted using Ludlum Model 4337 and Model 4368 gas proportional detectors, coupled with Ludlum Model 2360 scaler/ratemeters. MARSSIM recommends the use of Poisson summation statistics to estimate the probability of detecting a small number of counts that may indicate the possible presence of alpha contamination during a relatively short observation period. The equation for estimating the probability of detecting 1 or more counts is:

P(n>1) = 1 - e[((GE + B)t))/60] [A.1]

where:

P(n>1) = Probability of getting 1 or more counts during the time interval G = Source activity (disintegrations per minute, dpm)

B = Background count rate (counts per minute, cpm)

E = Detector efficiency (counts/disintegration) t = Dwell time over source (sec)

A1

The probability of detecting 2 or more counts is given by:

P(n>2) = 1 -( e[((GE + B)t)]/60] - ((GE+B)(t))/60). e[((GE + B)t)]/60] [A.2]

Using these parameters, detection probability calculations for a contamination level of 100 dpm/100 cm2 were performed for a scan rate of half of detector width per second (i.e., dwell times of 2 seconds). The probabilities of detecting a single alpha count during a 2s dwell time are approximately 33% for the 4368 detector and 52% for the 4337 detector. Because of the higher background count rate associated with the 4337 floor monitor detector, MARSSIM (Appendix I) recommends using 2 counts as a screening value when scanning for alpha contamination. The probability of detecting 2 counts with the larger detector increases to approximately 82%. Whenever a count is detected, the detector is paused over the surface for 10 seconds to determine whether there is actually elevated alpha activity present, in which case, a static measurement is then performed. A 10 second pause results in a 90% or greater probability of identifying the presence of alpha activity exceeding 100 dpm/100 cm2. Although the calculated scan detection probabilities may appear relatively low, it should be noted that historic records and characterization surveys have not identified any potential for alpha contamination in this facility.

Alpha Activity Static Measurements Static measurements of alpha surface activity are performed using 4368 detectors, with the same background and response characteristics as indicated above for alpha scanning. A static measurement is performed by placing the detector on the surface for a 2minute integrated count. The minimum detectable alpha contamination level (MDC) is calculated as follows:

MDC = [3 + 4.65 (BKGD)1/2]/(efficiency factors)(detector area/100)(count time) [A.3]

The resulting value is approximately 63 dpm/100 cm2.

Beta Scans Surface scans for beta activity are conducted using Ludlum Model 4337 and Model 4368 gas proportional detectors, coupled with Ludlum Model 2360 scaler/ratemeters. The detector is passed over the surface at a rate of 0.5 detector width/sec, while maintaining the distance from the detector to the surface at approximately 0.5 cm. The audible signal from the instrument is monitored by the surveyor. Detectable changes in the count rate are noted, and the immediate area resurveyed at a reduced speed to confirm the change in audible signal and, if applicable, to identify the boundary of the impacted area. The minimum detectable count rate (MDCR) is a function of the background count rate (BKGD) in counts per minute (cpm) and the time (i) in seconds that the detector is within close proximity to the source of radiation. Equation 66 of NUREG1507 provides the following relationship:

MDCR = d [BKGD*i/60]1/2

60/i [A.4]

A high probability (95%) of true detection is the objective, and the survey is willing to accept a high A2

probability of falsepositive detections (60%) with resulting investigations. The value of d is selected from Table 6.1 in NUREG1507 to be 1.38.

To account for less than ideal survey performance, a surveyor efficiency factor (p) of (0.5)1/2 was also incorporated into the final calculation of beta scan sensitivity as follows:

. [A.5]

. / /

The resulting values are approximately 1500 dpm/100 cm2 for the 4368 detector and an average of 390 dpm/100 cm2 for the 4337 detector. If only a single 100 cm2 area is present, the scan sensitivity for the 43 37 detector would be approximately 2280 dpm.

Beta Activity Static Measurements Static measurements of beta surface activity are performed using 4368 detectors. A static measurement is performed by placing the detector on the surface for a 2minute integrated count. The minimum detectable beta contamination level (MDC) is calculated as follows:

MDC = [3 + 4.65 (BKGD)1/2]/(efficiency factors)(detector area/100)(count time)

The resulting value is approximately 470 dpm/100 cm2.

Removable Alpha and Beta Activity Measurements Smears for removable activity are counted for 2 minutes in a Ludlum Model 2929 alpha/beta counter. The backgrounds are 1 alpha cpm and 25 beta cpm; 4 detection efficiencies are 0.25 alpha and 0.20 beta. Using the same equation (without probe area correction) as above for direct measurements yields removable activity MDCs of approximately 19 alpha dpm/100 cm2 and 90 beta dpm/100 cm2.

A3

Appendix B Layout of Individual Survey Unit Grids (Field Drawings Based Upon NUREG 1757 Guidance)

Room 60C, Access Control and Office Area, Survey Class 3 B1

Room 61A, Safeguards Laboratory, Survey Class 1 Room 61B, Reactor Room, Survey Class 1 (Refer to page 8 for initial room layout)

B2

Rooms 61A and 61B, Ceiling Grid Reactor &Laboratory Areas, Survey Class 2 B3

Room 135, Accelerator Room (North), Survey Class 1 Room 135, Accelerator Room (South), Survey Class 1 B4

Room 135, Ceiling Grid, Survey Class 2 B5

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Instrument and Measurement Information for FSS work:

All static measurement were preformed using Ludlum Instruments 4368 gas proportional detectors and Model 2360 scaler/rate meters.

All static measurements were 2minute integrated counts, one shielded and one unshielded, per location 60Co (a beta emitter) is the selected radionuclide of concern, but gross alpha measurements were also conducted For FSS simultaneous alpha/beta static measurements, the manufacturer's alpha background specification of 3 cpm was used unless a higher shielded alpha measurement was observed Survey unit data set summaries include measurements made with both instruments.

All instruments were response checked at the start and end of each shift.

Survey locations are noted in Appendix B to the FSS (circled locations are the random starting points)

The TAMU Radiological Safety Program specifies a residual contamination limits as follows:

a. no detectable contamination above background, i.e., not more than twice background levels

b. the determination of no detectable contamination above background must be made with a detector which has been response checked within the past 12 months ands which is suitable for measuring the type(s) of radiation expected (page 30 of the 2004 revision to the RSP Manual)

Instrumentation:

M 2360 scaler/ ratemeter: 276980 M 2360 scaler/ ratemeter: 268488 4368 gas prop detector 95080 4368 gas prop detector 94819 calibration due: 6/1/2017 calibration due: 5/31/2017 C1

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 60C Office Area, Class 3 data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 0.5 unshielded cpm 150.5 shielded cpm 3 shielded cpm 149 net cpm 2.5 net cpm 1.5 TRUE static point #2 unshielded cpm 3 unshielded cpm 168.5 shielded cpm 3 shielded cpm 157 net cpm 0 net cpm 11.5 TRUE static point #3 unshielded cpm 3 unshielded cpm 184 shielded cpm 3 shielded cpm 154 net cpm 0 net cpm 30 TRUE static point #4 unshielded cpm 0.5 unshielded cpm 153 shielded cpm 3 shielded cpm 154 net cpm 2.5 net cpm 1 TRUE static point #5 unshielded cpm 0.5 unshielded cpm 164.5 shielded cpm 3 shielded cpm 106 net cpm 2.5 net cpm 58.5 TRUE static point #6 unshielded cpm 0.5 unshielded cpm 136 shielded cpm 3 shielded cpm 130.5 net cpm 2.5 net cpm 5.5 TRUE static point #7 unshielded cpm 3.5 unshielded cpm 180 shielded cpm 3 shielded cpm 110 net cpm 0.5 net cpm 70 TRUE static point #8 unshielded cpm 4 unshielded cpm 114 shielded cpm 3 shielded cpm 109.5 net cpm 1 net cpm 4.5 TRUE static point #9 unshielded cpm 3.5 unshielded cpm 179 shielded cpm 3 shielded cpm 153 net cpm 0.5 net cpm 26 TRUE static point #10 unshielded cpm 2 unshielded cpm 160 shielded cpm 3 shielded cpm 161 net cpm 1 net cpm 1 TRUE static point #11 unshielded cpm 2 unshielded cpm 171 shielded cpm 3 shielded cpm 168.5 net cpm 1 net cpm 2.5 TRUE C2

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 2 unshielded cpm 102 shielded cpm 3 shielded cpm 83.5 net cpm 1 net cpm 18.5 TRUE static point #13 unshielded cpm 3 unshielded cpm 119.5 shielded cpm 3 shielded cpm 93 net cpm 0 net cpm 26.5 TRUE static point #14 unshielded cpm 3 unshielded cpm 184 shielded cpm 3 shielded cpm 157 net cpm 0 net cpm 27 TRUE static point #15 unshielded cpm 2.5 unshielded cpm 184.5 shielded cpm 3 shielded cpm 148 net cpm 0.5 net cpm 36.5 TRUE static point #16 unshielded cpm 4 unshielded cpm 154.5 shielded cpm 3 shielded cpm 133 net cpm 1 net cpm 21.5 TRUE static point #17 unshielded cpm 2 unshielded cpm 93 shielded cpm 3 shielded cpm 91 net cpm 1 net cpm 2 TRUE static point #18 unshielded cpm 3.5 unshielded cpm 183 shielded cpm 3 shielded cpm 151.5 net cpm 0.5 net cpm 31.5 TRUE static point #19 unshielded cpm 4 unshielded cpm 165.5 shielded cpm 3 shielded cpm 150.5 net cpm 1 net cpm 15 TRUE static point #20 unshielded cpm 3 unshielded cpm 157 shielded cpm 3 shielded cpm 140 net cpm 0 net cpm 17 TRUE static point #21 unshielded cpm 1 unshielded cpm 95 shielded cpm 3 shielded cpm 85 net cpm 2 net cpm 10 TRUE C3

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 61A Safeguards Lab, Class 1 data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 1.5 unshielded cpm 200 shielded cpm 3 shielded cpm 144 net cpm 1.5 net cpm 56 TRUE static point #2 unshielded cpm 2 unshielded cpm 203 shielded cpm 3 shielded cpm 144 net cpm 1 net cpm 59 TRUE static point #3 unshielded cpm 2 unshielded cpm 202 shielded cpm 3 shielded cpm 140 net cpm 1 net cpm 62 TRUE static point #4 unshielded cpm 2 unshielded cpm 159 shielded cpm 3 shielded cpm 125.5 net cpm 1 net cpm 33.5 TRUE static point #5 unshielded cpm 4 unshielded cpm 159 shielded cpm 3 shielded cpm 140 net cpm 1 net cpm 19 TRUE static point #6 unshielded cpm 1.5 unshielded cpm 149 shielded cpm 3 shielded cpm 127 net cpm 1.5 net cpm 22 TRUE static point #7 unshielded cpm 2.5 unshielded cpm 154 shielded cpm 3 shielded cpm 143 net cpm 0.5 net cpm 11 TRUE static point #8 unshielded cpm 0.5 unshielded cpm 173.5 shielded cpm 3 shielded cpm 126 net cpm 2.5 net cpm 47.5 TRUE static point #9 unshielded cpm 4 unshielded cpm 110 shielded cpm 3 shielded cpm 93 net cpm 1 net cpm 17 TRUE static point #10 unshielded cpm 3.5 unshielded cpm 123 shielded cpm 3 shielded cpm 86 net cpm 0.5 net cpm 37 TRUE static point #11 unshielded cpm 1.5 unshielded cpm 156 shielded cpm 3 shielded cpm 148 net cpm 1.5 net cpm 8 TRUE C4

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 3 unshielded cpm 176 shielded cpm 3 shielded cpm 137.5 net cpm 0 net cpm 38.5 TRUE static point #13 unshielded cpm 3 unshielded cpm 165 shielded cpm 3 shielded cpm 125 net cpm 0 net cpm 40 TRUE static point #14 unshielded cpm 3 unshielded cpm 137 shielded cpm 3 shielded cpm 135.5 net cpm 0 net cpm 1.5 TRUE static point #15 unshielded cpm 1.5 unshielded cpm 109 shielded cpm 3 shielded cpm 101 net cpm 1.5 net cpm 8 TRUE static point #16 unshielded cpm 1.5 unshielded cpm 106.5 shielded cpm 3 shielded cpm 94.5 net cpm 1.5 net cpm 12 TRUE static point #17 unshielded cpm 2 unshielded cpm 122 shielded cpm 3 shielded cpm 89.5 net cpm 1 net cpm 32.5 TRUE static point #18 unshielded cpm 1.5 unshielded cpm 104.5 shielded cpm 3 shielded cpm 126 net cpm 1.5 net cpm 21.5 TRUE static point #19 unshielded cpm 0.5 unshielded cpm 146.5 shielded cpm 3 shielded cpm 77 net cpm 2.5 net cpm 69.5 TRUE static point #20 unshielded cpm 2.5 unshielded cpm 165 shielded cpm 3 shielded cpm 156.5 net cpm 0.5 net cpm 8.5 TRUE C5

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 61B Reactor Room, Class 1 data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 3 unshielded cpm 163 shielded cpm 3 shielded cpm 125 net cpm 0 net cpm 38 TRUE static point #2 unshielded cpm 3.5 unshielded cpm 167 shielded cpm 3 shielded cpm 149 net cpm 0.5 net cpm 18 TRUE static point #3 unshielded cpm 4.5 unshielded cpm 168 shielded cpm 3 shielded cpm 141 net cpm 1.5 net cpm 27 TRUE static point #4 unshielded cpm 5 unshielded cpm 167.5 shielded cpm 3 shielded cpm 136.5 net cpm 2 net cpm 31 TRUE static point #5 unshielded cpm 3 unshielded cpm 182.5 shielded cpm 3 shielded cpm 144 net cpm 0 net cpm 38.5 TRUE static point #6 unshielded cpm 2.5 unshielded cpm 158 shielded cpm 3 shielded cpm 164.5 net cpm 0.5 net cpm 6.5 TRUE static point #7 unshielded cpm 2 unshielded cpm 175.5 shielded cpm 3 shielded cpm 135.5 net cpm 1 net cpm 40 TRUE static point #8 unshielded cpm 2 unshielded cpm 186 shielded cpm 3 shielded cpm 166.5 net cpm 1 net cpm 19.5 TRUE static point #9 unshielded cpm 1.5 unshielded cpm 174 shielded cpm 3 shielded cpm 161.5 net cpm 1.5 net cpm 12.5 TRUE static point #10 unshielded cpm 3.5 unshielded cpm 166 shielded cpm 3 shielded cpm 132 net cpm 0.5 net cpm 34 TRUE static point #11 unshielded cpm 1 unshielded cpm 173 shielded cpm 3 shielded cpm 150.5 net cpm 2 net cpm 22.5 TRUE C6

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 0.5 unshielded cpm 185.5 shielded cpm 3 shielded cpm 158 net cpm 2.5 net cpm 27.5 TRUE static point #13 unshielded cpm 2.5 unshielded cpm 177.5 shielded cpm 3 shielded cpm 151 net cpm 0.5 net cpm 26.5 TRUE static point #14 unshielded cpm 3.5 unshielded cpm 148.5 shielded cpm 3.5 shielded cpm 127 net cpm 0 net cpm 21.5 TRUE static point #15 unshielded cpm 4 unshielded cpm 167 shielded cpm 3 shielded cpm 146.5 net cpm 1 net cpm 20.5 TRUE static point #16 unshielded cpm 6 unshielded cpm 176 shielded cpm 3 shielded cpm 127.5 net cpm 3 net cpm 48.5 TRUE static point #17 unshielded cpm 5.5 unshielded cpm 169 shielded cpm 3 shielded cpm 152 net cpm 2.5 net cpm 17 TRUE static point #18 unshielded cpm 4 unshielded cpm 167.5 shielded cpm 3 shielded cpm 148.5 net cpm 1 net cpm 19 TRUE static point #19 unshielded cpm 3 unshielded cpm 222.5 shielded cpm 3 shielded cpm 147 net cpm 0 net cpm 75.5 TRUE static point #20 unshielded cpm 1 unshielded cpm 108.5 shielded cpm 3 shielded cpm 107.5 net cpm 2 net cpm 1 TRUE static point #21 unshielded cpm 2 unshielded cpm 120 shielded cpm 3 shielded cpm 89 net cpm 1 net cpm 31 TRUE C7

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 61 A & B Ceiling, Class 2 data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 2 unshielded cpm 135 shielded cpm 3 shielded cpm 124.5 net cpm 1 net cpm 10.5 TRUE static point #2 unshielded cpm 1 unshielded cpm 139 shielded cpm 3 shielded cpm 99 net cpm 2 net cpm 40 TRUE static point #3 unshielded cpm 2 unshielded cpm 133 shielded cpm 3 shielded cpm 112 net cpm 1 net cpm 21 TRUE static point #4 unshielded cpm 1.5 unshielded cpm 177 shielded cpm 3 shielded cpm 141 net cpm 1.5 net cpm 36 TRUE static point #5 unshielded cpm 2.5 unshielded cpm 120.5 shielded cpm 3 shielded cpm 99 net cpm 0.5 net cpm 21.5 TRUE static point #6 unshielded cpm 1 unshielded cpm 140 shielded cpm 3 shielded cpm 119.5 net cpm 2 net cpm 20.5 TRUE static point #7 unshielded cpm 1.5 unshielded cpm 124.5 shielded cpm 3.5 shielded cpm 133.5 net cpm 2 net cpm 9 TRUE static point #8 unshielded cpm 3 unshielded cpm 152 shielded cpm 3 shielded cpm 127 net cpm 0 net cpm 25 TRUE static point #9 unshielded cpm 4 unshielded cpm 126 shielded cpm 3 shielded cpm 94 net cpm 1 net cpm 32 TRUE static point #10 unshielded cpm 0 unshielded cpm 155.5 shielded cpm 3 shielded cpm 132.5 net cpm 3 net cpm 23 TRUE static point #11 unshielded cpm 1 unshielded cpm 158 shielded cpm 3 shielded cpm 137.5 net cpm 2 net cpm 20.5 TRUE C8

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 1 unshielded cpm 146.5 shielded cpm 3 shielded cpm 120 net cpm 2 net cpm 26.5 TRUE static point #13 unshielded cpm 1 unshielded cpm 121.5 shielded cpm 3 shielded cpm 117 net cpm 2 net cpm 4.5 TRUE static point #14 unshielded cpm 3 unshielded cpm 177 shielded cpm 3 shielded cpm 115.5 net cpm 0 net cpm 61.5 TRUE static point #15 unshielded cpm 3 unshielded cpm 118 shielded cpm 3 shielded cpm 134.5 net cpm 0 net cpm 16.5 TRUE static point #16 unshielded cpm 2.5 unshielded cpm 126.5 shielded cpm 3.5 shielded cpm 129.5 net cpm 1 net cpm 3 TRUE static point #17 unshielded cpm 2 unshielded cpm 138.5 shielded cpm 3 shielded cpm 115.5 net cpm 1 net cpm 23 TRUE static point #18 unshielded cpm 1.5 unshielded cpm 117.5 shielded cpm 3 shielded cpm 129.5 net cpm 1.5 net cpm 12 TRUE C9

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 135, N Floor, Accel Room, Class 1 data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 1 unshielded cpm 149 shielded cpm 3 shielded cpm 86 net cpm 2 net cpm 63 TRUE static point #2 unshielded cpm 4 unshielded cpm 167.5 shielded cpm 3 shielded cpm 110 net cpm 1 net cpm 57.5 TRUE static point #3 unshielded cpm 4 unshielded cpm 140.5 shielded cpm 3 shielded cpm 116 net cpm 1 net cpm 24.5 TRUE static point #4 unshielded cpm 4.5 unshielded cpm 153 shielded cpm 3 shielded cpm 105.5 net cpm 1.5 net cpm 47.5 TRUE static point #5 unshielded cpm 6 unshielded cpm 157.5 shielded cpm 3 shielded cpm 99.5 net cpm 3 net cpm 58 TRUE static point #6 unshielded cpm 2 unshielded cpm 140.5 shielded cpm 3 shielded cpm 103 net cpm 1 net cpm 37.5 TRUE static point #7 unshielded cpm 1 unshielded cpm 148.5 shielded cpm 3.5 shielded cpm 111.5 net cpm 2.5 net cpm 37 TRUE static point #8 unshielded cpm 1.5 unshielded cpm 198 shielded cpm 3 shielded cpm 102 net cpm 1.5 net cpm 96 TRUE static point #9 unshielded cpm 2.5 unshielded cpm 148.5 shielded cpm 3 shielded cpm 111.5 net cpm 0.5 net cpm 37 TRUE static point #10 unshielded cpm 1.5 unshielded cpm 136.5 shielded cpm 3 shielded cpm 90 net cpm 1.5 net cpm 46.5 TRUE static point #11 unshielded cpm 1.5 unshielded cpm 153.5 shielded cpm 3 shielded cpm 102.5 net cpm 1.5 net cpm 51 TRUE C10

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 1.5 unshielded cpm 144.5 shielded cpm 3 shielded cpm 101.5 net cpm 1.5 net cpm 43 TRUE static point #13 unshielded cpm 2.5 unshielded cpm 135.5 shielded cpm 3 shielded cpm 104 net cpm 0.5 net cpm 31.5 TRUE static point #14 unshielded cpm 2.5 unshielded cpm 138.5 shielded cpm 3 shielded cpm 98 net cpm 0.5 net cpm 40.5 TRUE static point #15 unshielded cpm 5 unshielded cpm 132 shielded cpm 3 shielded cpm 107.5 net cpm 2 net cpm 24.5 TRUE static point #16 unshielded cpm 6 unshielded cpm 144.5 shielded cpm 3.5 shielded cpm 109 net cpm 2.5 net cpm 35.5 TRUE static point #17 unshielded cpm 3 unshielded cpm 199 shielded cpm 3 shielded cpm 181.5 net cpm 0 net cpm 17.5 TRUE static point #18 unshielded cpm 1.5 unshielded cpm 153.5 shielded cpm 3 shielded cpm 102 net cpm 1.5 net cpm 51.5 TRUE C11

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 135, S Floor, Accel Room, Class 1 data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 2 unshielded cpm 117 shielded cpm 3 shielded cpm 73 net cpm 1 net cpm 44 TRUE static point #2 unshielded cpm 3.5 unshielded cpm 126 shielded cpm 3 shielded cpm 88.5 net cpm 0.5 net cpm 37.5 TRUE static point #3 unshielded cpm 3.5 unshielded cpm 145.5 shielded cpm 3 shielded cpm 83.5 net cpm 0.5 net cpm 62 TRUE static point #4 unshielded cpm 1 unshielded cpm 160.5 shielded cpm 3 shielded cpm 91.5 net cpm 2 net cpm 69 TRUE static point #5 unshielded cpm 2.5 unshielded cpm 145.5 shielded cpm 3 shielded cpm 96 net cpm 0.5 net cpm 49.5 TRUE static point #6 unshielded cpm 1.5 unshielded cpm 155.5 shielded cpm 3 shielded cpm 94 net cpm 1.5 net cpm 61.5 TRUE static point #7 unshielded cpm 3 unshielded cpm 150.5 shielded cpm 3.5 shielded cpm 108.5 net cpm 0.5 net cpm 42 TRUE static point #8 unshielded cpm 2 unshielded cpm 157.5 shielded cpm 3 shielded cpm 96 net cpm 1 net cpm 61.5 TRUE static point #9 unshielded cpm 3.5 unshielded cpm 165.5 shielded cpm 3 shielded cpm 104 net cpm 0.5 net cpm 61.5 TRUE static point #10 unshielded cpm 1 unshielded cpm 118 shielded cpm 3 shielded cpm 90.5 net cpm 2 net cpm 27.5 TRUE static point #11 unshielded cpm 2 unshielded cpm 117 shielded cpm 3 shielded cpm 101.5 net cpm 1 net cpm 15.5 TRUE C12

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 1.5 unshielded cpm 128 shielded cpm 3 shielded cpm 101 net cpm 1.5 net cpm 27 TRUE static point #13 unshielded cpm 0.5 unshielded cpm 142 shielded cpm 3 shielded cpm 91.5 net cpm 2.5 net cpm 50.5 TRUE static point #14 unshielded cpm 4.5 unshielded cpm 146 shielded cpm 3.5 shielded cpm 91.5 net cpm 1 net cpm 54.5 TRUE static point #15 unshielded cpm 1.5 unshielded cpm 145 shielded cpm 3 shielded cpm 93 net cpm 1.5 net cpm 52 TRUE static point #16 unshielded cpm 4.5 unshielded cpm 153.5 shielded cpm 3 shielded cpm 108 net cpm 1.5 net cpm 45.5 TRUE static point #17 unshielded cpm 2.5 unshielded cpm 138 shielded cpm 3 shielded cpm 106.5 net cpm 0.5 net cpm 31.5 TRUE static point #18 unshielded cpm 1 unshielded cpm 153.5 shielded cpm 3 shielded cpm 105.5 net cpm 2 net cpm 48 TRUE C13

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 135, N Ceiling, Accel Room, Class 2data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 2.5 unshielded cpm 107 shielded cpm 3 shielded cpm 84.5 net cpm 0.5 net cpm 22.5 TRUE static point #2 unshielded cpm 2 unshielded cpm 96 shielded cpm 3 shielded cpm 92 net cpm 1 net cpm 4 TRUE static point #3 unshielded cpm 1 unshielded cpm 102 shielded cpm 3 shielded cpm 96.5 net cpm 2 net cpm 5.5 TRUE static point #4 unshielded cpm 1.5 unshielded cpm 100.5 shielded cpm 3 shielded cpm 105 net cpm 1.5 net cpm 4.5 TRUE static point #5 unshielded cpm 3 unshielded cpm 96 shielded cpm 3 shielded cpm 116.5 net cpm 0 net cpm 20.5 TRUE static point #6 unshielded cpm 3 unshielded cpm 90.5 shielded cpm 3 shielded cpm 82 net cpm 0 net cpm 8.5 TRUE static point #7 unshielded cpm 6.5 unshielded cpm 107 shielded cpm 3.5 shielded cpm 102.5 net cpm 3 net cpm 4.5 TRUE static point #8 unshielded cpm 3 unshielded cpm 102.5 shielded cpm 3 shielded cpm 100 net cpm 0 net cpm 2.5 TRUE static point #9 unshielded cpm 1.5 unshielded cpm 91.5 shielded cpm 3 shielded cpm 79 net cpm 1.5 net cpm 12.5 TRUE static point #10 unshielded cpm 2 unshielded cpm 101 shielded cpm 3 shielded cpm 93 net cpm 1 net cpm 8 TRUE static point #11 unshielded cpm 2 unshielded cpm 94.5 shielded cpm 3 shielded cpm 94 net cpm 1 net cpm 0.5 TRUE C14

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 2 unshielded cpm 82 shielded cpm 3 shielded cpm 90 net cpm 1 net cpm 8 TRUE static point #13 unshielded cpm 3.5 unshielded cpm 102.5 shielded cpm 3 shielded cpm 88.5 net cpm 0.5 net cpm 14 TRUE static point #14 unshielded cpm 2.5 unshielded cpm 96 shielded cpm 3 shielded cpm 89 net cpm 0.5 net cpm 7 TRUE static point #15 unshielded cpm 1.5 unshielded cpm 95.5 shielded cpm 3 shielded cpm 94 net cpm 1.5 net cpm 1.5 TRUE static point #16 unshielded cpm 2.5 unshielded cpm 101.5 shielded cpm 3 shielded cpm 108.5 net cpm 0.5 net cpm 7 TRUE static point #17 unshielded cpm 2 unshielded cpm 89.5 shielded cpm 3.5 shielded cpm 88.5 net cpm 1.5 net cpm 1 TRUE static point #18 unshielded cpm 2 unshielded cpm 92 shielded cpm 3 shielded cpm 92.5 net cpm 1 net cpm 0.5 TRUE C15

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Room 135, S Ceiling, Accel Room, Class 2data from 2 minute integrated counts Meets release criteria ?

static point #1 unshielded cpm 0.5 unshielded cpm 84.5 shielded cpm 3 shielded cpm 90.5 net cpm 2.5 net cpm 6 TRUE static point #2 unshielded cpm 2 unshielded cpm 101.5 shielded cpm 3 shielded cpm 75.5 net cpm 1 net cpm 26 TRUE static point #3 unshielded cpm 2 unshielded cpm 88.5 shielded cpm 3 shielded cpm 87 net cpm 1 net cpm 1.5 TRUE static point #4 unshielded cpm 1 unshielded cpm 145 shielded cpm 3 shielded cpm 145.5 net cpm 2 net cpm 0.5 TRUE static point #5 unshielded cpm 2 unshielded cpm 86.5 shielded cpm 3 shielded cpm 125.5 net cpm 1 net cpm 39 TRUE static point #6 unshielded cpm 2 unshielded cpm 93.5 shielded cpm 3 shielded cpm 85 net cpm 1 net cpm 8.5 TRUE static point #7 unshielded cpm 2.5 unshielded cpm 104.5 shielded cpm 3.5 shielded cpm 99.5 net cpm 1 net cpm 5 TRUE static point #8 unshielded cpm 0.5 unshielded cpm 107 shielded cpm 3 shielded cpm 102.5 net cpm 2.5 net cpm 4.5 TRUE static point #9 unshielded cpm 0 unshielded cpm 94 shielded cpm 3 shielded cpm 80.5 net cpm 3 net cpm 13.5 TRUE static point #10 unshielded cpm 1.5 unshielded cpm 96 shielded cpm 3 shielded cpm 85.5 net cpm 1.5 net cpm 10.5 TRUE static point #11 unshielded cpm 3 unshielded cpm 98 shielded cpm 3 shielded cpm 89.5 net cpm 0 net cpm 8.5 TRUE C16

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary static point #12 unshielded cpm 2 unshielded cpm 88 shielded cpm 3 shielded cpm 89.5 net cpm 1 net cpm 1.5 TRUE static point #13 unshielded cpm 3.5 unshielded cpm 86.5 shielded cpm 4 shielded cpm 97 net cpm 0.5 net cpm 10.5 TRUE static point #14 unshielded cpm 2 unshielded cpm 94 shielded cpm 3 shielded cpm 94.5 net cpm 1 net cpm 0.5 TRUE static point #15 unshielded cpm 1.5 unshielded cpm 102.5 shielded cpm 3 shielded cpm 89.5 net cpm 1.5 net cpm 13 TRUE static point #16 unshielded cpm 1 unshielded cpm 105.5 shielded cpm 3 shielded cpm 92 net cpm 2 net cpm 13.5 TRUE static point #17 unshielded cpm 1.5 unshielded cpm 90.5 shielded cpm 3 shielded cpm 100 net cpm 1.5 net cpm 9.5 TRUE static point #18 unshielded cpm 3 unshielded cpm 90 shielded cpm 3 shielded cpm 91.5 net cpm 0 net cpm 1.5 TRUE C17

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Instrument and Measurement Information for health physics support and scoping work:

All static measurement were preformed using Ludlum Instruments 4393 dual phosphor detectors and Model 2360 scaler/rate meters.

Ludlum Measurments Model 449 pancake GM detectors and Model 3 scaler/ratemeter were used to evaluate smaller areas inaccessbile with the 4393 detectors All static measurements were 2minute integrated counts.

60 Co (a beta emitter) is the selected radionuclide of concern, but gross alpha measurements were also conducted All instruments were response checked at the start and end of each shift.

The TAMU Radiological Safety Program specifies a residual contamination limits as follows:

a. no detectable contamination above background, i.e., not more than twice background levels

b. the determination of no detectable contamination above background must be made with a detector which has been response checked within the past 12 months ands which is suitable for measuring the type(s) of radiation expected (page 30 of the 2004 revision to the RSP Manual)

This definition was used for health physics surveys to determine area and equipment contamination status and for monitoring of personnel.

Instrumentation:

M 2360 scaler/ ratemeter: 268494 M 2360 scaler/ ratemeter: 202442 4393 scint. Detector 268604 4393 scint. Detector 182266 calib due: 12/29/2016 calib due: 12/7/2016 M 2929 Dual channel scaler 99045 M 3 Ratemeter 269208 Detector: 43101 133007 449 GM pancake detector ES0054 calib due: 2/4/2017 calib due: 6/28/2017 C18

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Misc Survey Data, Class 1 Areas Meets release criteria ?

Room 61A glass reducer gross cpm 4 gross cpm 85 bkg cpm 3 bkg cpm 105 net cpm 1 net cpm 20 TRUE Room 61A glass drain trap gross cpm 1 gross cpm 109 bkg cpm 3 bkg cpm 105 net cpm 2 net cpm 4 TRUE Room 61A glass elbow gross cpm 2 gross cpm 93 bkg cpm 3 bkg cpm 105 net cpm 1 net cpm 12 TRUE Room 61A, glass elbow @ twist gross cpm 4 gross cpm 99 bkg cpm 3 bkg cpm 105 net cpm 1 net cpm 6 TRUE Room 61A, glass line unshielded cpm 3 unshielded cpm 102 shielded cpm 3 shielded cpm 105 net cpm 0 net cpm 3 TRUE Room 61A, glass line @ clamp unshielded cpm 3 unshielded cpm 83 shielded cpm 3 shielded cpm 105 net cpm 0 net cpm 22 TRUE Six swipes collected: maximum count rates = 1 ncpm alpha, 4 ncpm betagamma.

Piping and associated hardware was removed and disposed as nonradioactive waste.

Room 61B overhead shield plugunshielded cpm 1 unshielded cpm 81 shielded cpm 1 shielded cpm 74 net cpm 0 net cpm 7 TRUE Room 61 B source room well Wunshielded cpm 2 unshielded cpm 84.5 (static measurement at bottom shielded cpm 3 shielded cpm 86 net cpm 1 net cpm 1.5 TRUE Room 61 B source room well Wunshielded cpm 1 unshielded cpm 63.5 (static measurement at bottom shielded cpm 3 shielded cpm 70 net cpm 2 net cpm 6.5 TRUE Room 61 B source room well Wunshielded cpm 3.5 unshielded cpm 70.5 (static measurement at bottom shielded cpm 3 shielded cpm 67

net cpm 0.5 net cpm 3.5 TRUE C19

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary C20

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Example Field Surveys:

Scoping survey info Room 135 (Accel Room) swipe data Scoping survey info Rooms 61A & 61B (Safeguards Lab &

Reactor Room) Misc equipment survey data C21

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Scoping survey info Room 61B (Reactor Room) Storage area source wells C22

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary 61B Reactor Room - Conduit penetration surveys: initial and followup:

C23

Appendix C - Zachry Engineering Center FSS Static Measurements and Health Physics Survey Data Summary Scoping survey info - Room 135 (Accel Room) floor shield plug penetrations over the reactor:

C24

v t e Letter Sequence Request
TAC:MF6159, (Approved, Closed)
Initiation Request, Request, Request, Request, Request, Request, Request, Request Acceptance... Administration Questions Answers Results Approval Other: ML17005A416
MONTHYEAR2016-12-20 [Table View]

ML17010A057

Text

SUBJECT:

SUMMARY

2.0 INTRODUCTION

11.0 REFERENCES

SUMMARY

SUMMARY

2.0 INTRODUCTION

11.0 REFERENCES

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