ML20215C215
| ML20215C215 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 09/30/1986 |
| From: | Withers B PORTLAND GENERAL ELECTRIC CO. |
| To: | Varga S Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-3.D.3.4, TASK-TM TAC-61289, TAC-63157, NUDOCS 8610100165 | |
| Download: ML20215C215 (29) | |
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Bart D Weers Vce Presdent September 30, 1986 Trojan Nuclear Plant Docket 50-344 License NPF-1 Director of Nuclear Reactor Regulation ATTN: Mr. Steven A. Varga Director, PWR-A Project Directorate No. 3 U.S. Nuclear Regulatory Commission Washington DC 20555
Dear Sir:
NUREG-0737. III.D.3.4. Control Room Habitability
REFERENCES:
- 1) NRC (Varga) to PGE (Withers) Letter Regarding Control Room Habitability Safety Evaluation Report, June 16, 1986
- 2) PGE (Withers) to NRC (Varga) Letter, Control Room Ventilation, June 4, 1986
- 3) PGE (Withers) to NRC (Varga) Letter, Updated FSAR Amendment 5, September 30, 1986
- 4) PCE (Withers) to NRC (Varga) Letter, License Change Application 142, September 30, 1986 In Reference 1, it was concluded that the revised III.D.3.4 analysis submitted by PGE in Reference 2 meets the acceptance criteria of General Design criteria 19 with regard to radiation doses to control room personnel.
Reference 1 also noted that the revised III.D.3.4 analysis, with regard to toxic gas, would be evaluated when submitted.
The revised toxic gas analysis has been completed and is provided in Attach-ments A and B. The analysis is summarized in revised FSAR Section 6.4 sub-g mitted with Reference 3. The analysis justifies deletl?n of the ammonia g
detectors and sulfur dioxide detectors. In place of the detectors, human detection, along with administrative controls and training of control room h
P h 3 I I a s w won stee. emm1 own 972ca ,
._ . . _ . _ _ _ _ _ i
t N Ger1rd MCorryxwiy Mr. Steven A. Varga September 30, 1986 Page 2 personnel, will be utilized to provide protection from these gases. Pro-posed Technical Specification changes are provided in Reference 4. In addition, the standard information requested in NUREG-0737, Item III.D.3.4, for control room habitability evaluations is included in Attachment C.
Furthermore, our current plan for implementing control room habitability design changes is provided in Attachment D. A schedule for completion of each proposed modification is also provided.
Sincerely, Bart D. Withers Vice President Nuclear Attachments
q Mr. Steven A. Varga September 30, 1986 s Attachment A 1 INTRODUCTION Page 1 of 10
( In the updated FSAR Section 6.4 (Amendment 3 dated July 1985),
Habitability Systems, chlorine is identified as a potential hazard to the control room operators if an accidental spill occurred. As stated in the FSAR, chlorine detectors have been installed in both the Chlorine Building and the control room for purposes of detection and subsequently isolation of the control room. The chlorine detector at the control room air intake will automatically isolate the control room ventilation system upon detection of chlorine concentrations at I ppm. The possible sources of these chemicals are: on-site storage and Burlington Northern railroad on the west side of the plant.
The criteria of Regulatory Guide 1.78 is used specifying that operators must have at least two minutes to put on self contained breathing apparatus.
In early 1981, NUREG/CR-1741 entitled "Models for the Estimation of Incapacitation Times Following Exposures to Toxic Gases or Vapors" was
( published. The report presents a methodology to predict operator incapacitation for one-time exposure to toxic chemicals. It consisted of using 5 models (A-E) covering significant physiological and toxicological effects to humans.
The Chlorine Analysis was then undertaken to insure that the present control room ventilation system and chlorine monitor adequately protect j the control room operators from an accidental chlorine spill. The concentration models were based on NUREG-0570, and the incapacitation models on NUREG/CR-1741.
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. g Mr. Steven A. Varga September 30, 1986 i 2 CONCENTRATION MODELS f,'**h"of10
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( The analytical models used to calculate the concentration of chlorine in the control room atmosphere in the event of a spill are consistent with those described in NUREG-0570 (Ref. 1).
These models include the following bases and assumptions:
- a. Consistent with the criteria of Regulatory Guide 1.78, one container of chlorine (tank car or cylinder) was assumed to fail, releasing all of its '
contents.
- b. That fraction of chlorine which would flash to a gas at atmospheric pressure is assumed to be released as a puff. The remaining chlorine is assumed to spread uniformly on the ground and evaporate over time. It is assumed conservatively that no losses of chlorine occur as a result of absorption into the ground, flow into the river, cleanup operations, or chemical reactions.
( c. The initial puff due to flashing, as well as the continuous plume due to evaporation, is transported (and diluted) by the wind to the control room air intake.
- d. Atmospheric dispersion factors are calculated using the methodology of Regulatory Guide 1.78 and NUREG-0570. Dilution due to building wake effects from the plant structures using Meteorology and Atomic Energy (Reference 9) methodology (Section 3.142 page 112) is conservatively considered. The building cross-sectional area orthogonal to the wind speed is applied to account for the building wake correction factor in the atmospheric dispersion factors calculation.
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q Mr. Steven A. Varga September 30, 1986 o Attachment A.
Page 3 of 10
- e. Concentrations in the control room as a function of time were calculated
( for both normal control room ventilation without automatic isolation and control room normal ventilation with automatic isolation. Subsequently, the latter case assumed inleakage from the adjacent areas following isolation.
3 NUREG/CR-1741 MODELS Human exposure to airborne toxic materials produces a wide range of physiological and toxicological effects. For incapacitation effects there is a threshold concentration below which the body can eliminate, transform or otherwise act on the chemical to negate its effects. Above this threshold, there are two principal physiological modes which dominate: concentration dependence and dose dependence. For concentration dependent chemicals, the total dose received is not as important as the concentration of the chemical during exposure. Dose dependent chemicals produce an effect that is directly related to the
( total exposure regardless of the concentration at any given time.
NUREG/CR-1741 presents 5 models to describe incapacitation. However Chlorine at the Trojan Nuclear Plant belongs in the first or "A" model which is described below:
Model A. Concentration Dependent - Immediate Sensory Irritants:
This model describes a procedure for predicting the time to l incapacitation for immediate sensory irritants (e.g. Ammonia, l Chlorine, and Sulfur Dioxide). The effects are concentration and not j dose dependent.
Chemicals classified as immediate sensory irritants are corrosive or desiccant in their action. They inflame skin or mucous membrane especially when moist. They stimulate nerve ending in the eyes, nose, and oral cavity and inhibit respiration. They have essentially I the same effect on animals as on humans and the exposure
- , Mr. Steven A. Varga
- September 30, 1986 Attachment A Page 4 of 10 4 concentration is of greater significance than the duration of the
. exposure.
4 CHEMICAL DESCRIPTION FOR CHLORINE, C12 Presented below is a descriptive summary for chlorine . The information is taken from literature on the subject. The summary focuses on the effects chlorine has on human beings.
Chlorine in its gaseous form is greenish-yellow in color. It has a disagreeable, suffocating and irritating odor which is readily detectable at 3-5 ppm. Irritant effects to eyes, nose, throat and/or face were noted at low concentrations. Effects on the upper and lower respiratory tracts and pulmonary edema were reported at high concentrations. Chlorine becomes highly dangerous for exposures of 30 minutes at 40-60 ppm; it becomes fatal for exposures of 30-60 minutes at 800 ppm and fatal in a few breaths at 1000 ppm (Reference 2).
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5 ANALYSIS PERFORMED The Bechtel standard computer code T0XGAS (NE314) was used to calculate the concentrations of chlorine and the resulting incapacitation times in the control room. Two types of analyses were performed:
I. No control room isolation. This analysi.s was performed to determine the need for chlorine detection and automatic isolation.
- 2. Control room isolation. This analysis was performed to insure that the chlorine detectors and control room ventilation systems adequately protect the operators.
~ . . , - _ . _ _ _ . _ _ . _ . . _ . . . _ ~ _ - . . . _ .,_ ,.
Mr. Steven A. Varga g
September 30, 1986 Attachment A Control Room Isolation Not Considered
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An analysis of a control room without isolation was performed to determine which of the following sources of chlorine pose a hazard to the l control room operators if accidentally spilled:
- 2. 90 ton railroad tank car transported on the Burlington Northern railroad on the west side of the plant.
Results of this analysis indicate that both onsite and offsite chlorine require further investigation.
Control Room Isolation Considered 1
Further analysis was performed for onsite and offsite chlorine assuming automatic isolation of the control room. A monitor setpoint of 1 ppm was
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assumed (present detection level for the monitor). A total of 6 seconds delay time prior to isolation was used; 3 seconds for the monitor to actuate after the concentration at the intake reached the setpoint level and 3 seconds for the damper to close. Conservatively, no travel time from the control room intake to the control room was assumed. Utilizing Standard Review Plan 6.4, this analysis conservatively assumed that the inleakage rate into the control room following isolation consisted of one half of the pressurization make-up flow plus 10 cfm of leakage from control room ingress and egress.
Evaluation showed that chlorine transported through the Burlington Northern Railroad on the west side of the plant still poses a threat to the control room operators if all of the control inleakage rate is
! assumed to come directly from the outside air, i.e. the control building envelope is not considered. In reality, following control room i isolation, the leakage into the control room will be primarily from i
' Mr. Steven A. Varga
, September 30, 1986 Attachment A Page 6 of 10
, adjacent building areas, and not directly from the outside air.
Therefore, the analysis was modified conservatively to take into account
'( leakage from adjacent areas to the control room.
If chlorine concentrations at the air intake exceed the monitor setpoint, the outside air dampers are closed and the normal ventilation system (CB-2) intake fan is shut off automatically and the system operates in full recirculation mode. The procedures are then to manually shut off i the normal ventilation system to the control room and to initiate the emergency ventilation system (CB-1) in a full recirculation mode through the charcoal filters. The ventilation systems for the other areas in the control building are also automatically secured, thus no direct outside air eters the control building and, consequently, the control room.
Since the control room is isolated, inleakage into the control room can
! only be from the adjacent areas. A detailed description of the adjacent areas is shown below:
North: The north wall of the control room is the outside wall of the control building. This is a concrete block wall 2' 10" thick with no penetrations to the outside.
East: The east wall is adjacent to the auxiliary building. This is also a concrete block wall 2' 10" thick with no significant air leakage between the buildings.
West: The west wall is adjacent to the turbine building (2' 10" thick concrete block). One leaktight door leads from the turbine building to the viewing gallery.
t l South: The south wall is adjacent to the remainder of the control building. There are two leaktight doors and one security door. The l upper portion of the control room is adjacent to the mechanical equipment room. Sealed HVAC penetrations and one leaktight door l connect the mechanical equipment room to the control room.
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.,-,.__~-__-_4 ,_ _ - _ . -- __,. .. . - - - . ~ , _ , _ - - - .
. . Mr. Steven A. Varga
- i. s September 30, 1986 Attachment A Page 7 of 10 ceilina: The ceiling of the control room is also the roof of the
( control building. This roof is a concrete structure with sealed pentrations for the roof drains.
Floor: The cable spreading room is directly below the control room. A large number of sealed penetrations exist between these rooms.
Since the outside wall, the wall to the auxiliary building, and the ceiling of the control room are thick concrete structures with no penetrations, no leakage from the outside air is expected to occur.
Leakage is expected to occur from the outside to the mechanical equipment room through the air intake louvers. Since the normal ventilation system for the control building is not drawing air, no driving force exists, therefore this leakage is expected to be small. However, to bound uncertainties in the analysis, one half of the total control room inleakage was conservatively assumed to come through these sources and assumed to be at outside air concentrations.
il Most of the leakage into the control room will occur through the doors and penetrations to the control building. Since the control building ventilation system is secured, the only mechanism available for the I
chlorine to enter the control room is first to leak into the control building, mix slowly in the free air space available, then leak into the control room at a lowered concentration. Some leakage can occur through the door leading from the turbine building to the viewing gallery. The
- ventilation system of the turbine building is not secured and will be no more than 10 air changes per hour. This air change rate was conservatively used to represent the leakage into the areas adjacent to the control room. One half of the total control room inleakage was then j assumed to come from these areas.
Time between detection and incapacitation for both onsite and offsite chlorine were calculated to determine if the R.G.1.78 limit of 2 minutes was met, i I
Mr. Steven A. Varga September 30, 1986 Attachment A l . Page 8 of 10 6 RESU1.TS
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The study showed that in order to meet the two minute requirement, chlorine detection and automatic isolation of the ventilation sytem is required. Further, credit for inleakage from the building areas surrounding the control room is assumed.
- a. Onsite chlorine Results showed that the incapacitation times for all the cases considered are over 10 minutes, thus above the required 2 minute limit. The cases analyzed used different control room inleakages (150,190, 235, and 450 cfm) and monitor setpoints of 1 ppm and 5 ppm. These cases bounded the actual leakage rate into the control room.
- b. Offsite chlorine (B.N.R.R.)
Figure I shows the concentration as a function of time for each of the I control room inleakage sources and the resultant total control room concentration. Also shown on Figure 1 is the incapacitation function for the incapacitation model A. With this model, incapacitation is defined as the time that the function reaches unity. As shown on Figure 1, a total of 130 seconds is available between monitor alarm and incapacitation onset.
Therefore, the control room operators are adequately protected against a chlorine tank accident.
7 CONCLUSION As discussed above, the control room operators are adequately protected with the prese.nt chlorine detectors and control room ventilation system
! design. Chlorine detectors need to be set at a monitor setpoint of 1 ppm.
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. Mr. Steven A. Varga
. 's September 30, 1986 l Attachment A
- Page 9 of 10 8 REFERENCES
(
- 1. NUREG-0570 " Toxic Vapor Concentrations in the Control Room Following a Postulated Accidental Release", James Wing,USNRC-ONRR, dated June 1979 )
- 2. Effects of Exoosure to Toxic Gases - First Aid and Medical Treatment by Braker, Mossman and Siegel, Second Edition
- 3. Patty's Industrial Hvaiene and Toxicoloav by George D. and Florence E. Clayton, Volumes 2A & 2B, Third Edition.
- 4. Dept. of Transportation, " Coast Guard CHRIS Hazardous Chemical Data",
Oct. 1978.
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- 5. " Documentation of the Threshold Limit Value", Fourth Edition,1980, American Conference of Government Industrial Hygienists Inc.
- 6. " User Manual for Bechtel S.C.P. T0XGAS NE314 Release 2", Bechtel I'ower Corporation, May 1982. (Bechtel Proprietary)
- 7. NUREG/CR-1741 "Models for the Estimation of Incapacitation Times Following Exposure to Toxic Gases and Vapors", Gordon J. Smith, David E. Bennet, Sandia National Laboratories, Dec - 1980.
l
- 8. FSAR Section 6.4 (Amendment 3, July 1985)
- 9. Meteorology and Atomic Energy 1968 by David Slade U.S. Atomic Energy Commission, published July 1968 t.
Mr. Steven A. Var'ga September 30, 1986 ,,
Attachment A Page 10 of 10 FIGURE 1 Concentration (ppm)
Off-Site Chlorine Concentrations
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Monitor Alarm Incapacitation me %in) l
, Mr. Steven A. Varga
- September 30, 1986
- Attachment B 1 INTRODUCTION
(
In the updated FSAR Section 6.4 (Amendment 3 dated July 1985),
Habitability Systems, sulfur dioxide and anhydrous ammonia were identified as potential hazards to the control room operators if an accidental spill occurred. The possible source of these chemicals is the railroad on the east side of the Columbia River used by Burlington Northern Inc. and Union Pacific Railroad.
4 The criteria of Regulatory Guide 1.78 was used specifying that operators must have at least two minutes to put on self contained breathing apparatus.
In early 1981, NUREG/CR-1741 entitled "Models for the Estimation of Incapacitation Times Following Exposures to Toxic Gases or Vapors" was published. The report presents a methodology to predict operator incapacitation for one-time exposure to toxic chemicals. It consisted of using 5 models (A-E) covering significant physiological and toxicological
[ effects to humans.
This study was then undertaken to determine the possibility of eliminating the detectors for these chemicals by applying the techniques of NUREG/CR-1741. The analysis was done based on the present control room ventilation system for the Trojan Nuclear Plant.
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J Mr. Steven A. Varga
.- September 30, 1986
- Attachment B Page 2 of 10 2 CCNCENTRATION MODELS
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The analytical models used to calculate the concentratica of a toxic chemical in the control room atmosphere in the event of.a spill are consistent with those described in NUREG-0570 (Ref. 1).
These models include the following bases and assumptions:
- a. Consistent with the criteria of Regulatory Guide 1.78, one container of a
. toxic chemical (tank car or cylinder) was assumed to fail, releasing all of its contents.
- b. That fraction of the chemical which would flash to a gas at atmospheric pressure is assumed to be released as a puff. The remaining chemical is assumed to spread uniformly on the ground and evaporate over time. It is assumed conservatively that no losses of chemicals occur as a result of absorption into the ground, flow into the river, cleanup operations, or chemical reactions.
(
! c. The initial puff due to flashing, as well as the continuous plume due to evaporation, is transported (and diluted) by the wind to the control room air intake.
1 i d. Atmospheric dispersion factors are calculated using the methodology of Regulatory Guide 1.78 and NUREG-0570. Dilution due to building wake effects from the plant structures using Meteorology and Atomic Energy (Reference 9) methodology (Section 3.142 page 112) is conservatively considered. The building cross-sectional area orthogonal to the wind speed is applied to account for the building wake correction factor in the atmospheric dispersion factors calculation.
- e. Concentrations in the control room as a function of time were calculated assuming normal control room ventilation for anhydrous ammonia and sulfur dioxide.
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' Mr. Steven A. Varga September 30, 1986 Attachment B l Page 3 of 10
- - 3 NUREG/CR-1741IWDELS
(
Human exposure to airborne toxic materials produces a wide range of ,
physiological and toxicological effects. For incapacitation effects )
there is a threshold concentration below which the body can eliminate, transform or otherwise act on the chemical to negate its effects. Above this threshold, there are two principal physiological modes which dominate: concentration dependence and dose dependence. For concentration dependent chemicals, the total dose received is not as 4 important as the concentration of the chemical during exposure. Dose dependent chemicals produce an effect that is directly related to the total exposure regardless of the concentration at any given time.
NUREG/CR-1741 presents 5 models to describe incapacitation. However anhydrous ammonia and sulfur dioxide at Trojan Nuclear Plant fall into the range of the first or "A" model which is described below:
Model A. Concentration Dependent - Immediate Sensory Irritants:
I This model describes a procedure for predicting the time to
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incapacitation for immediate sensory irritants (e.g. Ammonia, Chlorine, and Sulfur Dioxide). The effects are concentration and not dose dependent.
Chemicals classified as immediate sensory irritants are corrosive or desiccant in their action. They inflame skin or mucous membrane especially when moist. They stimulate nerve endings in the eyes, nose, and oral cavity and inhibit respiration. They have essentially the same effect on animals as on humans and the exposure concentration is of greater significance than the duration of the exposure.
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f Mr. Steven A. Varga September 30, 1986
- Attachment B Page 4 of 10 4 CHEMICAL DESCRIPTION 4
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l Presented below is a descriptive summary of the two toxic chemicals that are in question at the Trojan Nuclear Plant. The information is taken from literature on the subject. The summaries focus on the effects these chemicals have on human beings. When such data was not available results on animals were presented.
t Anhydrous Ammonia, NH3 Ammonia is a colorless gas with a sharp, intensely irritating odor. It has an odor threshold of 46.8 ppm for humans (Reference 4). Complaint levels of 20-25 ppm were first observed. Human effects such as eye irritat, ion sometimes with lacrimation, nose, throat, and chest irritation (coughing, edema of lungs) were found at concentrations up to 700 ppm, depending on exposure time (Reference 2,3,5). The chemical then becomes lethal starting at 2000 ppm concentration even for exposures of a very
( short duration (Reference 2).
1 Sulfur Dioxide S02 Sulfur Dioxide is a colorless, irritating gas with a suffocating odor as
! sharp and pungent as burning sulfur (Reference 2,4). It is readily detectable in concentrations of 3-5 ppm by humans. Low concentrations
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create a taste sensation even before the odor becomes detectable. It causes throat irritation, coughing, constriction of the chest and l lacrimation and smarting of the eyes if concentrations of 8-12 ppm vapor in air is inhaled. A 150 ppm of concentrations can be endured only a few minutes due to eye irritation and effect on membranes of the nose, throat and lungs. Sulfur dioxide becomes highly dangerous at exposures of 30-60 minutes at 500 ppm and may be fatal for continued exposure to amounts greater than 1000-2000 ppm (Reference 2).
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Mr. Steven A. Varga September 30, 1986
- Attachment B Page 5 of 10 5 ANALYSIS PERFORMED
(. The Bechtel standard computer code T0XGAS (NE314) was used to perform the analysis. Using the results of the analysis a determination was made as to which toxic chemicals still required monitoring. It is assumed that the control room HVAC system is in normal operation during the postulated accident (i.e. that there is no control room isolation), and that chemical monitoring is achieved just by the operators' ability to detect the chemical. Using these assumptions the times to first detection of the chemical and the times to incapacitation were calculated. Chemicals that have at least 2 minutes between detection and incapacitation will not need to be monitored for operator protection.
An analysis of the control room without isolation was performed for sulfur dioxide and anhydrous ammonia which pose hazard to the control room operators.if accidentally spilled while being transported through the railroad on the east side of the Columbia River.
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. Mr. Steven A. Varga September' 30, 1986 Attachment B 6 RESULTS
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Anhydrous ammonia and sulfur dioxide allowed ample time from detection levels to incapacitation levels and a discussion of the results for each of these chemicals are presented below:
Anhydrous Amonia, NH3 Figure 1 presents the concentration of amonia at the air intake and inside the control room versus time. Results showed that without control room isolation and without operator action, it will take 4 minutes and 3 seconds for the operators to be incapacitated from the 25 ppm toxicity limit. Since amonia has a sharp and intensely irritating odor, incapacitation time can be measured from the time the odor threshold concentration of 46.8 ppm is reached. There are 3 minutes and 48 seconds available from the odor threshold level where the operators can decect amonia by smell and don breathing apparatus before incapacitation is reached.
[
Ammonia detector is no longer necessary since the operators have ample time to detect this chemical and don their breathing apparatus. However, l
the control room operators should be trained to detect the presence of amonia.
Sulfur Dioxide S02 Figure 2 presents the concentration of sulfur dioxide at the air intake and inside the control room versus time. Results showed that without control room isolation and without operator action, it will take 4 minutes and 16 seconds before the control room operators are incapacitated from the 5 ppm toxicity limit. Having a sharp and pungent odor like burning sulfur, incapacitation time can be measured from the 5
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Mr. Steven A. Varga September 30, 1986 Attachment B ppm odor threshold. There are also 4 minutes and 16 seconds #fE8manoNr
( threshold of 5 ppm where operators can detect sulfur dioxide by smell and don breathing apparatus until incapacitation is reached.
Sulfur dioxide detectors are, therefore, not necessary. However, the control room operators should be trained to detect the presence of this chemical.
Conclusion As discussed above, detectors are no longer required for anhydrous ammonia and sulfur dioxide. To insure that the control room operators are adequately protected, a training program to detect these chemicals by their distinctive odors and don their breathing apparatus will have to be instituted along with procedure changes to reflect the new protective measures required.
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. Mr. Steven A. Varga September 30, 1986
- Attachment B Page 8 of 10 7 REFERENCES
- 1. NUREG-0570 " Toxic Vapor Concentrations in the Control Room Following a Postulated Accidental Release", James Wing,USNRC-ONRR, dated June 1979
- 2. Effects of Exoosure to Toxic Gases - First Aid and Medical Treatment by Braker, Mossman and Siegel, Second Edition
- 3. Patty's Industrial Hvaiene and Toxicoloav by George D. and Florence 1 E. Clayton, Volumes 2A & 28, Third Edition.
- 4. Dept. of Transportation, " Coast Guard CHRIS Hazardous Chemical Data",
Oct. 1978.
(
- 5. " Documentation of the Threshold Limit Value", Fourth Edition,1980, American Conference of Government Industrial Hygienists Inc.
- 6. " User Manual for Bechtel S.C.P. T0XGAS NE314 Release 2", Bechtel Power Corporation, May 1982. (Bechtel Proprietary)
- 7. NUREG/CR-1741 "Models for the Estimation of Incapacitation Times Following Exposure to Toxic Gases and Vapors", Gordon J. Smith, David E. Bennet, Sandia National Laboratories, Dec - 1980.
- 8. FSAR Section 6.4 (Amendment 3, July 1985)
- 9. Meteorology and Atomic Energy 1968 by David Slade, U.S. Atomic Energy Commission, published July 1968
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l Mr. Steven A. Varg.a l
September 300 1985 ,,
Attachment B Page 9 of 10 FIGURE 1 l
I "O" " AnhydrousAmmoniaConcentration
,1 5_ . . .. . .. .. .. . .... ... . ..... . . . .. ..... . .. . . .... ... ... ..... . . ... . ......... ..... ..... .
yA. irIntaRe ,i :
1E4. . . . . . .. ... ... . ........
i - Control Roorn :
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1E2_ . .. .. .. . .. . ........ ... ... ..... .......
...... .OdorThreshold i : i i 1E1. . ... . ... . .. . . . . . . . .
- 1. ... . . . .. . . . . . . . . . . . . . .
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- 1E-2_ .. .. . . . . . . . . ... . . ...... .. .. ..
- .. ......
4 j : :
4 1E-3 I I I I i
0.1 0.5 1 5 10 l
i Time >'t hours;>
1 1
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Mr. Steven A. Varga
- I September 30,~1986 Attachment B Page 10 of 10 Sulfur Dioxide Concentration
. = = *..*.*.*.*. . ...... . . .. .. ........ .. .. ...e..e......... .
.. . . . . .... . . ....... . = = . .
m 1E3m . . . . ..... . . . . ... .... . . ..... . . . . . . -.. ..... .. ...
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, 1E2_ . . .. . .. .. . . ... . . .... ... . . . ...
1E1. .... . . ...... .. .. . . . .
OdotThreshold i
j :. :
- : ... i... . . . ..... ...,i 1E-1_ ..... ... ........ . ... . . .. . .. .,. .. . . . ... .. .....
4 1 E __2 _ .............. ... . . ... .. ... .... ..... ............. ..... :
J : :
1 1E-3 I I I I 0.1 0.5 1 5 10 Time l hours;> <
e Trojan Nuclear Plant Mr. Steven A. Varga
- Docket 50-344 September 30, 1986
. License NPF-1 Attachment C
< Page 1 of 4
! NUREG-0737, III.D.3.4 INFORMATION REOUIRED FOR CONTROL ROOM HABITABILITY 4
INFORMATION REQUIRED TROJAN DESIGN INFORMATION i
4 (1) Control room mode of operation, ie, pressuriza- (a) Radiological Accident i tion and filter recirculation for radiological l accident isolation or filter recirculation only The CB-1 system pressurizes the control room to j for chlorine release accident isolation 1/8" w.g. positive pressure with up to 525 cfm outside air. Recirculated air in addition to the makeup air will pass through a carbon adsorber filter for a total flowrate of 3000 cfm.
(FSAR 6.4.2.3 and 9.4.1.2.1) 1 q (b) Chlorine Release 4
- The CB-1 system recirculates the control room air through a carbon adsorber filter while the outside j isolation dampers are closed. (FSAR 9.4.1.2.1)
(2) Control room characteristics l (a) control room air volume Net Air Vol. = 81,300 ft3 (includes control room, supervisor / chart room and viewing gallery).
l (FSAR 6.4.2)
(b) control room emergency zone (control room The emergency zone includes control room, supervisor's I
critical files, kitchen washroom, computer room, chart room and viewing gallery,(FSAR Fig. 7.7-10).
! room, etc.)
i .' .
- ; Yr j (c) control room ventilation system schematic ' Refer'to FSAR Fig. 9.4-1. / ;
, with normal and emergency air-ficw'. rates -
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e Trojan Nuclear Plant Mr. Steven A. Varga Docket SC-344 September 30, 1986 License NPF-1 Attachment C Page 2 of 4 NUREG-0737, III.D.3.4 INFORMATION REQUIRED FOR CONTROL ROOM HABITABILITY INFORMATION REQUIRED TROJAN DESIGN INFORMATION (d) infiltration leakage rate 10 cfm unfiltered inleakage (for dose calculation) and 273 cfm (used in toxic gas analysis).
(e) high efficiency particulate air (HEPA) Refer to License Change Application 142, September 30, filter and charcoal adsorber efficiencies 1986.
(f) closest distance between containment and 145 ft to the CB-1 air intake.
control room ventilation air intake (g) layout of control room, air intakes, Con- Refer to FSAR 6.4.4.1, 6.4.4.2.1, and figures 7.7-10, tainment building, and chlorine, or other 12.3-1, and 12.3-33.
chemical storage facility with dimensions (h) control room shielding including radiation Refer to FSAR 12.3.2.4.
streaming from penetrations, doors, ducts, stairways, etc.
(1) automatic isolation capability-damper clos- Chlorine monitor response time 3 seconds ing time, damper leakage and area (FSAR 9.4.1).
Damper actuation time 3 seconds.
Damper flow area = 28.3 in2 (Dampers DM 10251A&B).
Damper leakage - No measurable leakage following refurbishment during testing in 1986 refueling outage.
The dampers are designed for < 11 cfm (FSAR 6.4.2.3).
(j) chlorine and/or toxic gas detectors (local At CB-2 intake and at the chlorine building or remote) (FSAR 9.4.1.2.1).
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e Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 September 30, 1986 License NPF-1 Attachment C Page 3 of 4 NUREG-0737, III.D.3.4 INFORMATION REOUIRED FOR CONTROL ROOM HABITABILITY INFORMATION REQUIRED TROJAN DESIGN INFORMATION (k) self-contained breathing apparatus avail- Five (FSAR 6.4.4.2.4).
ability (number)
(1) bottled air supply (hours supply) Eight bottles, 2.5 hrs for 5 men (FSAR 6.4.4.2.4).
(m) emergency food and potable water supply See FSAR Section 6.4.2.1.
(how many days and how many people)
(n) control room personnel capacity (normal See FSAR 6.4.4.2.4.
and emergency)
(o) potassium iodide drug supply 50 or more units of potassium iodide (FSAR 6.4.2.1).
(3) Onsite storage of chlorine and other hazard-ous chemicals i
(a) total amount and size of container 20 one ton cylinders (FSAR 9.3.6.2).
(b) closest distance from control room air Approximately 330 feet horizontally & 75 feet intake vertically (FSAR 6.4.4.2.1).
(4) Offsite manufacturing, storage, or transpor-tation facilities of hazardous chemicals (a) identify facilities within a 5-mile radius Refer to FSAR Tables 2.2-1 through 2.2-5.
(b) distance from control room Refer to FSAR Tables 2.2-1 through 2.2-5.
(c) quantity of hazardous chemicals in one Refer to FSAR Tables 2.2-1 through 2.2-5.
container
o Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 September 30, 1986 License NPF-1 Attachment C Page 4 of 4 NUREG-0737, III.D.3.4 INFORMATION REOUIRED FOR CONTROL ROOM HABITABILITY INFORMATION REQUIRED TROJAN DESIGN INFORMATION (d) frequency of hazardous chemical trans- Refer to FSAR Table 2.2-5.
portation traffic (truck, rail and barge)
(5) Technical Specifications (refer to standard technical specifications)
(a) chlorine detection system See License Change Application 142, September 30, 1986.
(b) control room emergency filtration system See License Change Application 142, September 30, 1986.
including the capability to maintain the control room pressurization at 1/8 in.
water gauge, verification of isolation by test signals and daseer closure times, and filter testing requirements JWL/GAZ/BLK/ cab 1098W.886
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Trojan Nuclear Plant Mr. Steven A. Varga
- Docket 50-344 September 30, 1986 License NPF-1 Attachment D Page 1 of 3 PROPOSED CONTROL ROOM HABITABILITY DESIGN MODIFICATIONS MODIFICATIONS BASIS SCHEDULE COMMENTS A. CONTROL ROOM BOUNDARY
- 1) Add redundant dampers to This will ensure that the con- 1987 DM-10501, 10503, & 10504. trol room envelope meets single- Outage failure criteria.
- 2) Secure all portions of CB-2 With portions of CB-2 operating 1988 This design change would eliminate upon toxic gas detection. in recire, potential exists for Outage the need for operator action to large negative pressure on out- secure CB-2 as is presently done side air dampers. This can per ONI-54.
result in toxic gas leaking by these dampers into control room.
B. CB-1
- 1) Replace dampers DM-10251A&B. These dampers are classified as 1988 safety-related but do not meet Outage state-of-the-art for this type service.
- 2) Periodically clean entire This will ensure flow is not Routinely system. degraded.
- 3) Change DM-10251A&B switches Human factors. 1988 to pull-to-lock. Outage
- 4) Replace fan-duct flexible This will ensure leak tightness. 1988 connections and institute Outage periodic replacement program.
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9 Trojan Nuclear Plant Mr. Steven A. Varga
- Docket 50-344 September 30, 1986 License NPF-1 Attachment D Page 2 of 3 MODIFICATIONS BASIS SCHEDULE COMMENTS
- 5) Modify doors on filter units This will ensure leak tightness. 1988 (reinforce /regasket). Outage Replace all other access doors on CB-1.
- 6) Provide permanent fix for This will ensure leak tightness. End of cooler drains to eliminate 1986 i potential for unfiltered air inleakage.
- 7) Add instrumentation per SRP Improves system diagnostics. 1988 As a minimum, permanent flow 6.5.1, Table 1, as necessary. Outage instruments to measure outside makeup air flow and total system flow, both of which are Tech Spec related values, should be added.
C. LOGIC
- 1) Provide SIS "B" to CB-2,3, To meet single-failure criteria 1988 4,5,6,&l0; relogic CB-2,3, for control room envelope, improve Outage 4,5,6,&l0; provide damper system operation.
position indication.
D. TOKIC GAS
- 1) Upgrade C12 detection. Detectors do not completely con- 1988 Modifications to be considered form with NRC guidance. Outage include: (1) upgrade to Cat. 1, (2) provide separation, (3) pro-tect from tornados, (4) provide automatic isolation of CB-1, (5) add redundant detector to Chlorine Building.
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Trojan Nuclear Plant Mr. Steven A. Varga
- Docket 50-344 September 30, 1986 License NPF-1 Attachment D Page 3 of 3 MODIFICATIONS BASIS SCHEDULE COISENTS E. COOLING
- 1) Enhance emergency cooling Existing CB-1 cooling capability 1988 Details of cooling modifications capability (eg, add stand- is marginal. Outage such as seismic design, emergency alone room coolers, modify power availability, etc, are being selected cabinets to improve evaluated.
ventilation).
BLK/kal 0748P.986
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