ML20210H768
| ML20210H768 | |
| Person / Time | |
|---|---|
| Site: | 07000734 |
| Issue date: | 07/25/1997 |
| From: | Cowan S, Gonzales L, Maschka P GENERAL ATOMICS (FORMERLY GA TECHNOLOGIES, INC./GENER |
| To: | |
| Shared Package | |
| ML20210H765 | List: |
| References | |
| NUDOCS 9708140186 | |
| Download: ML20210H768 (34) | |
Text
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DECONTAMINATION OF SELECTED GENERAL ATOMICS' g
ROOMS FOR RELEASE TO UNRESTRICTED USE (Building 30 Phase 1) l I
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July 25,1997 I
I Prepared By: Laura Q. Gonzales, Paul Maschka and Scott Cowan i
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p um use, PDR
TAB.LE OF CQRTENTS
. EASE LIST OF FIGURES
...........................................I LIST OF TABLES
......... i1 I N T R O D U CT IO N.................................................
...... 1 SITE DESCRIPTION
.................... 1 4
CRITERIA FOR RELEASE TO UNRESTRICTED USE.....................
..... 2 PREVIOUS ACTMTIES (HISTORY OF USE)..................................... 2 INSTRUMENTATION
.............. 2 DACKGROUND MEASUREMENTS
.......................................... 2 S U R VE Y S P E R F O R M E D...................................................... 3 Removal of items and Equipment......................................... 3 S u rve y Pla n......................................................... 3 Detailed Locations of Fixed Measurements and Smears........................ 5 RESULTS OF THE SURVEY MEASUREMENTS................................. 6 Scanning...........................................................6 Fixed Measurements.....................................
........... 6 Removable Centamination Surveys........................................ 6 Paint Samples and Additional Fixed Measurements on the Walls................ 6 Exposure Rate Measurements..................................
........ 7 ADDITION AL SU RVEYS....................................
.... 7 Scans........................................................ 7 Fixed Measurements.................................
........... 7 Removable Contamination Surveys..........................
....... 7 Exposure Rate Measurements........................................ 7 C O N C LU S I O N............................................
............... 8
I LIST OF FIGURES P498 Figure 1:
View of Site.......................................................... 9 Figure 2:
Building 30/31 Complex...............................................
10 Figure 3:
Building 30. Phase l Rooms...........................................
11 F%ure 4:
Final Removable Contamination Survey (Locations) in Room 115................
12
- F6gure 5:
Final Removable Contamination Survey (Locations) in Halhvey 124..............
13 Figure 6:
Final Removable Contamination Survey (Locations) in Room 125................
14 Figure 7:
Final Removable Contamination Survey (Locations) in Room 126................
15 Figure 8:
Final Removable Contamination Survey (Locations) in Room 127................. 16 Figure 9:
Firuf Removable Contamination Survey (Locations) in Room 128................
17 Figure 10:
Final Removable Contamination Survey (Locations) in Room 129...............
18 Figure 11:
Fixed Measurement Locations in Building 30 Phase i Rooms..................
19
- Figure 12:
Paint Sample Locations in Building 30. Phase i Rooms....................... 20 i
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I LlST OF TABLES Psae Table 1:
USNRC's Acceptable Surface Contamination Levels...........
.. 21 Table 2:
State of CA Acceptable Surface Contamination Levels.
... 22 Table 3:
List of instrumente 23 Table 4:
Background Meas, monts 24 Table 5:
Results of Radiation Scans and Fixed Measurements
. 25 Table 0:
Exposure Rate Measurements..................
27 Table 7:
Results of Removable Contamination Surveys 28 Table 8:
Paint Sample Results.......................................... 29 Table 9:
Fixed Measurements on Wall Surfaces Before and After Removal of Paint g
S a m ple...............
.. 30 W
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INTROAUCTION, General Atomics (GA)is continuing its efforts directed at decontaminating and obtaining the release to unrestricted use of selected laboratories and facilities on it's San Diego Site. GA has recently surveyed a group of rooms in GA's Building 30/31 Complex. These rooms have been designated in this report as ' Building 30 Phase l'. It is urgent that these rooms get released to unrestricted use as soon as possible.
The rooms in Building 30 to be released in Phase I are rooms 115,124 (a hallway),125,126, 127,128 and 12g; a layout of these rooms is shown in Figure 3. The total area to be released to unrestricted use is - 1487 ft'. GA intends to use these rooms in the future only for activities not involving radioactive materials.
in the past, only irradiated gemstones were handled in these rooms under a specific NRC license that allowed GA to irradiate and distribute gemstones to the public. The rest of the building previously housed various accelerators, and portions are currently being used to store radioactive material.
GA is requesting both the State of California and the Nuclear Regulatory Commission to release these rooms. This report documents the results of extensive and comprehensive measurements completed in the ' Building 30- Phase l' rooms to demonstrate that these rooms, meet the approved criteria for release to unrestricted use. Accordingly, GA is requesting that these rooms be released to unrestricted use.
SITE DESCRIPTION The location of Building 30 with respect to other facilities on the GA Site is shown in Figure 1. A layout of the Building 30/31 complex is shown in Figure 2. The rooms in Building 30 to be released in Phase I are rooms 115,124 (a hallway),125,126,127128 and 129; a layout of these rooms is shown in Figure 3.
A total of six (6) rooms and one hallway are included in ' Building 30 - Phase l'. The total area 8 as follows:
to be released to unrestricted use in the *Bullding 30-Phase l' rooms is - 1487 ft RQDm ft8 115 263 124 331 125 125 126 84 127 121 128 214 12g ME Total 1487 1
_-___-______m._____
..___-.-.-._m._
I CRITERIA FOR RELEASE TO UNRESTRICTED.USE Table 1 is taken from U.S. NRC's enteria for releasing facilities and equipment to unrestricted use. It has been incorporated into GA's SNM 696 license. The State of California's guidelines, "DHS Criteria for Release of Facilities and Equipment to Unrestricted Use," also known as "DECON 1", are summarized in Table 2.
I GA has conducted extensive and comprehensive surveys and sampling to demonstrate that the radiation levels in the rooms are below these guidelines.
EREylOUS ACTIVITIES (HISTORY OF USE)
GA's Work Authorization logs were searched in order to review the previous activities conducted in each lab and to identify the radionuclides of concern. Although an exhaustive g
search of the records was not completed, enough information was obtained to demonstrate that 3
detailed measurements in each room were needed. The only activity identified to have been performed in these rooms which involved radioactive materials was the counting of irradiated Demstones in the oJrly 1990's. Gemstones would be irradiated in GA's TRIGA* reactor facility and/or in the linear accelerator which was previously located in room 114 of Building 30 and counted in the Phase I rooms for radioactivity. GA had a specific NRC license which allowed the irradiation and distribution of irradiated gemstones. A survey of the rooms after the activity ended was completed in September and October 1993. No contamination was found. No g
other activities involving radioactive material have been identified.
B 1RSTRUMENTATION Table 3 is a list of instruments used during the radiological surveys. The table includes: (1) a description of the instrument, (2) the model and serial numbers of the rate meters and g
detectors, (3) instrument ranges, (4) calibration due dates, (5) typical efficiencies, and (6) 3 typical background count rates.
BACKGROUND MEASUREMENTS Four (4) different surfaces exist in the " Building 30 - Phase 1". These surfaces are made of cement block, tile over concrete, concrete, and drywall. Building 13 was selected for conducting background measurements because there has never been radioactive material used in this building, the age of the building, and because the various surfaces found in the Building 30 Phase I rooms could also be found in building 13. Background measurements were taken during July 1997.
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For background fixed measurements, shown in Table 4, the mean and standard deviation for each surface surveyed with the 100 cm' detector was calculated using equations 811 and 812 in NUREG/CR 5849 as shown below:
(8 11) p.g.,,,
a.
Average of 5 measurements (8 12)
U,GJ 8.*g Background measurements and minimum detectable activities (MDA's) for each type of surface and for various counting times are provided in Table 4. Minimum detectable activities (MDA's) for each type of surface, were calculated using equation (5 2) from NUREG/CR 5849 as shown below:
1 (5 2) 2,71 4.65/B,=t 3
l MDA=
(dpm/t00cm )
Where:
gon II, = background rate (cym)
I = count time (min)
E = effklency A = area of the detector (cm')
SURVEYS PERFORMEQ Bamoratoflimma_and Eaulomani in each room, allitems and equipment were surveyed prior to removal. No contaminated equipment was found during these surveys.
SMIY.ny P_lan After allitems and equipment were removed and a survey plan was developed based on the previous history of the rooms, the radionuclides of concem, the various types of surfaces and I
the potential for contamination. The physical characteristics of the rooms (vents, painted surfaces, unpainted surfaces, overhead structures, etc.) were inspected in determining the l
number of locations and types of surveys to be performed.
l Survey measurements for surface activity consisted of a combination of surface scans, direct l
measurements, and measurements of removable activity. The following is the survey plan which summarizes the surveys performed.
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Survey Plan for Building 30 - Phase ! Rooms (Tetal of-1487 ft ) Apnl28-29.1997 2
Room 115 Hallway 124 Room 125 Room 126 Room 127 Room 128 Room 129 263 ft 331 ft 125 n 84 a 121 n 214 n 2 349 ft 2
2 8
2 2
The onty hrstory of use invotsmg radcachve matenal was for 9% 6b c countmg amer irradiabon using a knear riccweis. The gen 6bws were actvated (only slight rernovable contauwWuva was ever detected on the geish es). No core ibon of the rooms occurred from thrs actnnty Floor 100% o scan No No No No No No No Floor 100% D scan Yes Yes Yes Yes Yes Yes Yes LowerWaDs (becom Yes Yes Yes Yes Yes Yes Yes 2m) 10% D scan Upper Walls -10%
No No No No No No No Dscan
- of Fixed 7
11 4
3 3
7 12 h
(2 rrun)
(2 mm)
(2 rrun)
(2 rnm)
G rmn)
(2 mm)
(2 rrun)
(see nso
- of Paint Samples 1
0 1
0 1
0 2
- 5
- 1
- 2 83 and #4
- of Smears 19 15 10 6
8 11
- 15
- iSee Uso 2
- of MK:roR Readngs Readrngs to be taken every 10 m (approximately every 3 m) at 1 m atmve the surface (total of at least 16 readegs).
Floor Drams?
None None None None None None None Floor Surface Tile Over Concrete Totai e or th 26 26 14 9
11 18*
27*
<r s u - a sw
- Revtsed from original plan.
4 M
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M M
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Detailed Locations of Fixed Measurements and Smears Room Fixed Measurements Smears Room 115 Fired Measurements (7)
Smears (19) 5 Floor 8
Floor i
Top of Shield Wall 4
Walls (1/ wall) 1 Wall 2
Top of Shield Wall
(
3 Top of Electncal Panels (1 each) 2 Bhnds Hollway 124 Ftxed Measurements (ii)
Smtirs (15) 7 Floor 8
Floor 4
Walls 4
Walls (1/ wall) i in Vent i
Out Vent 1
Top of Lights Room 125 Fixed Measurements (4)
Smears (10) 2 Floor 4
Floor 2
Wall 4
Walls (1/ wall) 1 in Vent i
Out Vent Room 126 Fixed Measurements (3)
Smears (6) 2 Floor 2
Floor 1
Wall 4
Walls (1/ wall)
Room 127 Fired Measurements (3)
Smears (8) 2 Floor 4
Floor 1
Wall 4
Walls (1/ wall)
Room 128 Ehed Measurements (7)
Smears (11)
- O Floor 6
Floor 1
Wall 4
Walls 1
Bhnds Room 129 Fixed M.casutemtats (12)
Smears (15)
- 9 Floor 9
Floor 3
Walls 4
Walls 1
Top of Electrical Panel 1
Bhnds
- Revised from original plan.
I RESULTS OF THE SURVEY MEASUREMENTS The rooms in Building 30 - Phase I were categorized as
- unaffected
- areas based on historical information and after no contamination was detected after scanning the floor.
Scannino Scanning was performed in each lab using floor monitors having a 425 cm' gas flow proportional detector. The floors received 100% coverage for beta contamination. The lower walls (~2 m up) received 10% coverage and upper walls were not surveyed. The results of the scans on the floors, upper walls and lower walls are provided in table 5. Readings were at or near background levels (see table 4 for background levels).
I Eixed Mea untmania Fixed measurements were performed using a beta gas flow proportional counter having a 1 E
cm ' detector, The counting time for fixed measurements was two (2) minutes in all rooms. For 3
fixed measurements, an appropriate background was determined for each type of surface and subtracted from the survey readings and the results converted to dpm/100 cm' using the efficiency of the detector (the detector size is 100 cm ').
The fixed measurements on the floor tile and other surfaces were taken in accordance with the survey plan and are provided in figure 11 and summarized in table 5. All results show that the levels were below the release criteria.
Removable Contamination Suryny.a l
Removable contamination measurements (smears) were performed on all surfaces including the floors, walls, and overhead structures including ducts, lights and I beams in accordance with the survey plan. An area of - 100 cm' was wiped with a filter paper and counted in GA's g
Health Physics Laboratory using low level alpha / beta gas flow proportional counting system.
5 The locations where smears were collected on the floors and walls of the labs are shown in figures 410. The results of all removable contamination surveys are provided in Table 7. All levels were below the release criteria (alpha and beta results were < 10 dpm/100 cm'.)
I Paln1Earnale7.andAdditional Fixed Measurements on the Walls Paint samples were collected about 1 m up from the floor at each of five (5) locations (shown in figure 12) on the original concrete block walls. Paint samples were not collected from walls made of drywall (allinner walls of the rooms) which were installed after the basic construction of this portion of the building. There is no history of use of radioactive materials which would have contaminated the drywall. The paint was collected in an area - 100 cm'.
The paint samples were analyzed using a low-level alpha / beta gas flow proportional counting I
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system; the results are provided in Table 8. All gross alpha and gross beta results were < 10
)
dpm/100 cm',
In every location where paint samples were collected, two (2) minute fixed measurements were 8
taken before and after removal of the paint. The results were converted to dpm/100 cm and are provided in Table 9. The highest result was < 178 dpm/100 cm'(tne MDA).
Exposure Rata.Measurementt Direct radiation exposure rate measurements using a microR meter were taken in every room one meter above the floor surface at approximately evenly spaced intervals throughout the lab.
The radiation levels were at or close to normal background radiation levels (see table 6 for results).
ADDITIONAL SURVEYS Additional surveys were performed by GA Health Physics Technicians independently of those technician (s) who performed the final surveys to verify that the radiation levels on the floors, walls and other structures in the Building 30. Phase I rooms were below the release criteria.
Esana
(
Scans along the corners of the floors and walls and up the center of the floor in each room (room 115,124,125,126,127,128, and 129 were conducted. The results of the scans showed only normal background levels.
Fixed Measurements A total of six, two minute fixed measurements were taken (at random locat!ons) as follows: One measurement in room 115,1 measurement in room 125,2 meesurements in room 127,1 measurement in room 128, and 1 measurement in room 129. E.ach result was < 178 dpm/100 cm').
Removable contamination survevs A smear survey was performed in the Building 30 - Phase I rooms. A total of 15 smears were taken as follows: Four (4) smears were taken in room 115, 5 smears were taken in room 124,1
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smear was taken in room 125,2 smears were taken in room 128 and 3 smears were taken in room 129. Each smear area was 100 cm', All smears showed activity levels < 10 dpm/100 cm' alpha and < 10 dpm/100 cm' beta.
Exposure Rate Measurements A microR survey was performed in all of the rooms using a Ludlum MicroR meter taken at 1 m from the surface of the floor or wall. The results ranged from 15 21 microR/hr, 7
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CONCLUSION 5'
einal contamination and radiation surveys provided in this report for these rooms designated as E
"Bullding 30 Phase 1" demonstrate that these rooms meet the approved guidelines for l
release to unrestricted use.
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i Figure 4: Removable Contamination Survey (Locations) in Building 30 - Phase I Room 115 14*8"
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-12' Numbers at the approximate locations of smears taken in Room 115 On floor (unless otherwise noted).
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Figure 5: Removable Contamination Survey (Locations) in Building 30 - Phase i Halfway 124 i
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Smears taken on the floor (unless otherwise noted).
13
Figure 6: Removable Contamination Survey (Locations) in Building 30 - Phase I Room 125 Room 125
- [
- 14'8"
-97"
-147"
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4'on waII 5(
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Smear taken on the foor (unicss otherwise noted) 14 W
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rw w w Figure 7: Removable Contamination Survey (Locations) in Building 30 - Phase i Room 126 Room 126 I
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-12' Numbers are the approximate locations of smears taken in Room 126 On Floor (unless otherwise noted) 15
Figure 8: Removable Contamination Survey (Locations) in Building 30 - Phase i Room 127
- 14*8"
-97
~147 s (on+ watt) 2 e
Room 127 Room 126 Room 125 8'
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4 Room 129 Room 128 Room 115 irr
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-12' Numbers are the approximate locations of smears taken in Room 127 Smears were taken on the floor (unless otherwise noted) 16 l[M M
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U t__J t__J Figure 9: Removable Contamination Survey (Locations) in Building 30 - Phase i Room 128
- 14'8" 0
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~12* - W Numbers are the approximate locations of smears taken in Room 128 Smears were taken on the floor (unless otherwise noted) 17
Figure 10: Removable Contamination Survey (Locations)in Building 30 - Phase 1 Room 129 4
- 14'8"
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~14'7"
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~12' Numbers are the approximate locations of smears taken in Room 129.
Smear taken on the floor (unless otherwise noted).
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a Figure 11: Fixed Measurement Results in Building 30 - Phase I Rooms
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-12' Notes.
2
- 1. Fixed measurement results are provided in dpna*100 cm.
- 2. The wall measurements were taken about 1 m up.
- 3. Each measurement was 2 minutes long.
4 No contamination was detected.
- 5. Scan results and the fixed measurement results are provded in Table S.
19
Figure 12 : Paint Sample Locations in Building 30 - Phase 1
-14'8*
Oc
-97
-14 7
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Room 127 Room 126 Room 125
,r Shield Halfway 124
-34' 5",
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-12' Q Paint Sample Locations and ID Number 20 M
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Table 1: USNRC'S ACCEPTABLE SURFACE CONTAMINATION LEVELS '
Nuclides' Average * *d Maximum 83 Removable 'd 6
6 (dpm/100cm')
(dpm/100cm'l (dpm/100cm')
U-nat. *U, *O, & associated decay products 5.000 a 15.000 a 1,000 a Transuranics, *Ra,22 era,2"Th,2Th 22'Pa, 100 300 20 mAc, '24, *l Th-nt(. 2Qh, "Sr, mRa, *Ra, "O, Si, "31, *l 1,000 3.000 200 Beta / gamma emitters (nuclides with decay modes other than alpha emission or 5,000 15,000 1,000 I
spontaneous fission) except "Sr and other noted above.
I a Where surface contamination by both alpha-and beta / gamma-emrtting nuchdes exists, the Irnita established for alpha, and beta / gamma emitting nuclides should apply independently, b As used in this table dpm (distntegrations per minute) means the rate of emission by radcactive matenal as determined by correcting the counts per minute observed by an appropnate detector for background, efbency, an geometnc factors associated with the instrumentation.
c Measurements of average contaminant should not be averaged over more than 1 square ineter For objects of less surface area, the average should be dertved for each such object.
a d The maximum contamination level applies to an area of not more than 100 cm,
a e The amount of removable radioactive matenal per 100 cm of surface area snould be determined by wiping that area with dry filter or soft absorbent paper. applying moderate pressure, and assessing the amount of radioactive material on the wipe with an appropnate instrument of known efriciency. When removable contamination on objects of less surface area is determined, then pertinent levels should be reduced proportionally and the entire surface should be wiped.
f The aserege and maximum radiation levels associated with surface contamination resulting from beta-gamma emitters should not exceed 0 2 mrad /hr at i cm and 1.0 mrad /hr at 1 cm, respechvely, measured through not more than 7 milligrams per square centimeter of total absorber.
Guidelines For Decontamination of Facilities and Equipment Prior to Release for Unrestricted Use or Termination of Ucensee For byproduct, Source, or Special Nuclear Material, USNRC, July 1982, incorporated into GA's SNM 696 hcense.
2,
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Table 2: STATE OF CA ACCEPTABLE SURFACE CONTAMINATION LEVELS '
Nuclides' Average *"
Maximum
- C Removable * "
2 2
(dpm/100cm )
(dpm/100cm
(dom /100cm '
U-nat,2"U, *"U, & associated decay 5,000 15,000 1,000 products Transuranics, 8"R a, 22 era, "Th, 22eTh, 100 300 20 28'Pa,23'Ac,12sg, tag Th-nat,2"Th "Sr, r:3Ra, 82'Ra, 222U, '3*l, 1,000 3,000 200 W
ing, isig Beta / gamma emitters (nuclides with decay modes other inan alpha emission or 5,000 15,000 1,000 spontaneous fission) except "Sr and other noted above I
Where surf ace contamination by both alpha and beta / gamma-emitting nuclides exists, the limits a
=
established for alpha. and betalgamma-emitting nuclides should apply independently.
b As used in this table dpm (disintegrations per minute) means the rate of emission by radioactive matenal as determined by correcting the counts per minute observed by an appropriate detector for background, efficiency, an geometric factors associated with the insteumentation.
c Measurements of average contaminant should not be averaged over more than i square meter. For objects of less surf ace ares;, the average should be derrved for each such object.
3 d
The maximum contamination level applies to an area of not more than 100 cm.
e The amount of removable radioactive material per 100 cm of surface area should be determined by 3
wiping that area with dry filter or soft absorbent paper, applying moderate pressure, and assessing the amount of radioactive material on the wipe with an appropriate instrument of known efficiency. When removable contamination on objects of less surface area is determined, then pertinent levels should be reduced proportionally and the entire surface should be wiped.
f The average and maximum radiation levels associated with surface contamination resulting from beta-gamma emitters should not exceed 0.2 mrad /hr at 1 cm and 1.0 mrad /hr at 1 cm, respectively, measured through not mom than 7 milligrams per square centimeter of total absorber, Guidelines For Decontartunation of F acilities and Equiprnent Pnor to Release for Unrestncted Use or Termination of Licenses For byproduct. Source, or Special Nuclear Matenal, also known as "Decon-1" incorporated into GA's State of CA Radioactive Matenals License.
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-- uman t
r t_; -- _t i
TABLE 3: LIST OF INSTRUMENTS RATEMETER DETECTOR RANGE (CPM)
CAllBRATION EFFICIENCY BACMGROUND DESCRIPTION DUE DATE (cpm) 8 Ludium Model 4347 gas Four Unear Ranges 7-9-97 a = 2015%
Vanes accorJeg Actrve Probe Area = 434crn The detector and ratemeter are Modet 2221 propor*aonal t434 cm')
0 - 500 000 & One Th-230 to surface bemg comtmed and mounted on a rou around cart The instru wnt teatures a S/N 97287 Alpha detector Log 50 - 500.000 scanned.
s'atoflow system. quck connects a portable gas bottle and a mear's to S/N 086238 See Table 4 adjust the height of the detector from the floor for optanum 6. Li s Ludium Ludlum Model 43-37 Four Unear Ranges 7-9-97 p = 21.0%
Vanes accordeg Actnre Probe Area = 434cm. The detector and ratemeter are comtmed z
Model 2221 gas 5, Wee (434 0 - 500.000 & One St-90 to surface bemg and mounted on a rot around cart The instrument features a state-flow S/N 73701 cm ) Beta detector Log 50 - 500 000 scanned system, quck connects, a portable gas bottle and a means to adpust the r
S/N 083265 See Table 4 beght of the detedor from the floor for optanum wb. s Ludlum Ludium Model 43-68 Four isnear ranges 9-1-97 p = 34 98%
Vanes accordeg 100 cm' gas flowr wi~.6 counter.
Model 2221 100 cm' propMenal 0 - 500.000 & one St-90 to surface bemg S/N 88423 counter S/N 119444 log 50-500.000 scanned See Table 4 Ludium Medes RCA 6199 coupled to Five PJnges 1 inch x 1 inch Nat (TT) scintiltator is mourWed intemaRy 19 M<:roR Meter a Nat (TI) Semt fia^or 0 - 5 mRN S/N 87120 9-24-97 N/A 10-18 pR/hr 7-28-97 Canberra Gas Flow N/A Count smears 26-30 %
a < 0.5 Low Levet al 9 gasrww..at counteg system Low Level Proportional for rerweable p<20 al D Counter Detector al D surface Model 2404 contamination
)
l 23
I TABLE 4: Background Measurements 100 cm' beta detector (2 Minute Counts) 0)
Background Material Average of 5 measurements MDA (dpm/100 cm')
(2 minutes each) total counts i 2 SD i
Drywall 472110 148 Concrete Block wall 689 1 14 178 Concrete 752128 186 Linoleum over Concrete 6031 14 167 d
Floor Monitor Background Scan Results '
g Beta / gamma Scan Range (counts per minute) m Surface Drywall 754 1133 Concrete block wall 1242-1503 Concrete 973-1346 Linoleum over Concrete 873-1373 "8 Measurements taken July 17-18,1997.
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24 I
3 m
m i
T U -l J
Table 5: Results of Radiation Scans and Fixed Measurements Fixed Measurements (100 cm' beta detector)
Range of Totat
Background
Maximum Figure Type of' Surface Count Beta Activity or g
Time
.damimum Activity MDA cpm Measurements (counts / time (dpm/100cm')
indicated)
%)
Room 115 Floor, tde (100%)
11 803-1198 5
2 591-645 603 1 14
<167 167 Walls (10 % 2m up) 11 517-1328 1
2 632 689114
<178 178 Top of Shield Wafi 11 1
2 565 689114
<178 178 Hallway 124 l
7 2
542-652 603 i 14
<167 167 Floor, tde (100%)
11 743-972 l
4 2
509-566 472i10
<148 148 Walls (10% 2m up) 11 741-936 Room 125 l
2 2
667-696 603 14
<167 167 Floor, tde (100%)
11 781-1008 l
2 2
707-720 689114
<178 178 Walls (10% 2m up) 11 803-1172 Room 126 Floor, tile (100%)
11 776-933 2
2 6254 55 603 1 14
<167 167 Walls (10% 2m up) 11 800-1147 1
2 649 689214
<178 178 Room 127 l
2 2
632-679 603 1 14
<167 167 Floor, tile (100%)
11 762-993 l
1 2
571 472 10
<148 148 Walls (10% 2m up) 11 749-1125 25
Tcble 5: Results of Radiation Secns cnd Fixed Measurements Fixed Measurements (100 cm' beta detector)
Floor monitors Figure Range of TW
Background
Maximum Type of Surface Count seta ActMer or 8
Beta
- of Readings Activity cpm Measurements (counts / time (dpml100cm')
indicated)
Room 128 Floor, ble (100%)
11 803-1032 6
2 568-671 603 1 14
<167 167 Wa!!s (10% 2m up) 11 727-1014 1
2 544 689114
<178 178 Room 129 Floor, tile (100%)
11 793-1049 9
2 624-667 603 1 14
<167 167 Watts (10% 2m up) 11 738-1002 3
2 540-645 689 114
<178 178 26 E
M M
M M
M M
M M
M M
M M
M
4 W
TABLE 6: EXPOSURE RATE MEASUREMENTS Building 30 Phase i Rooms Location Number of Range of Exposure Rates Measurements at 1 Meter (pR/hr)
Room 115 4
14 15 Hallway 124 5
13-14 Room 125 2
15 (both readings)
Room 126 1
15 Room 127 2
13-14 Room 128 4
12 (all 4 readings)
Room 129 4
12 (all 4 readings)
Background Measurements Location /
Number of Range of Exposure Rates Type of Surface Measurements at 1 Meter (pR/hr)
Breezeway and sidewalk outside 5
11 14 building by lab 534 Outside Building 13 (near 1
20-21 I
concrete floors and concrete block walls)
Outside Building 13 (near 5
14-19 stairwells) l I
I 27
_ _____o
I Table 7: Results of Removable Contamination Surveys Removable Activity Measurements Number of Figure Maximum Activity Smears on each Surface g
Total Number (dpm/100 cm')
of smears Alpha Beta Room 115 8
Floor 4
Walls (1/ wall) 2 Top of Shield Wall 4
39
<jo
<10 3
Top of Electncal Panels (1 each) 2 Blinds Hallway 124 8
Floor 4
Walls (1/ wall) 1 in Vent 5
15
<10
<10 1
Out Vent 1
Top of Lights Room 125 4
Floor 4
Walls (1/ wall) 6 10
<10
<10 1
in Vent 1
Out Vent Room 126 l
2 Floor 7
6
<10
<10 4
Walls (1/ wall) l Room 127 Smears (8) 4 Floor 8
8
<10
<10 4
Walls (1/ wall)
Room 128 6
Floor 4
Walls 9
11
<10
<10 g
i Blinds E
9 Floor 4
Walls 10 15
<10
<10 1
Top of Electrical Pano!
1 Blinds 28 I
a TABLE 8: Paint Sample Results Sample location Sample ID Figure Alpha (maximum)
Beta (maximum)
No.
dpm/100 em' dpm/100 cm' r
Room 125
- 1 12
<10
<10 l
Room 127
- 2 12
<10
<10 Room 129
- 3 12
<10
<10 Room 129
- 4 12
<10
<10 Room 115
- 5 12
<10
<10 1
1 I
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Table 9: Fixed Measurements on Wall Surfaces Before and After Removal of Paint Sample Before Paint Sample Removal After Paint Sample Removal
Background
"A Location Reading 2 minute 2 minute 8 " ** *
(dpmI100 cm')
(counts /2 minutes) reading (dpml100 cm')
reading (dpml100 cm')
Room 125 #1 concrete block 689 1 14 718
<178 774
<178 178 Room 127 #2 covete block 689114 604
<178 714
<178 178 Room 129 #3 concrete block 689 14 610
<178 637
<178 178 Room 129 #4 concrete block 689 t 14 580
<178 622
<178 178 Room 115 #5 concrete block 689 14 460
<178 476
<178 178 i
l l
l l
l 30 M
M M
M M
M M
M M
M M
.