ML063040190

Response to Request for Additional Information Regarding License Amendment Request: Removal of TSP from Palisades Containment

ML063040190
Person / Time
Site:	Palisades
Issue date:	10/30/2006
From:	Harden P Nuclear Management Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML063040190 (28)

Text

Palisades Nuclear Plant Operated by Nuclear Management Company, LLC October 30,2006 10 CFR 50.91 (a)(5)

U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Palisades Nuclear Plant Docket 50-255 License No. DPR-20 Response to Request for Additional Information Recrardinn License Amendment Request: Removal of TSP from Palisades Containment By letter dated March 20, 2006, pursuant to 10 CFR 50.91 (a)(5), Nuclear Management Company, LLC (NMC) requested Nuclear Regulatory Commission (NRC) review and approval of a proposed license amendment for the Palisades Nuclear Plant (PNP).

NMC is proposing to remove tri-sodium phosphate (TSP) from the containment building at PNP as an interim measure until the long term resolution of GSI-191 is implemented.

By electronic email dated August 11, 2006, the NRC sent a request for additional information (RAI) regarding the proposed license amendment request. Enclosure 1 provides the response to the RAI for PNP.

A copy of this RAI response has been provided to the designated representative of the State of Michigan.

Summaw of Commitments This letter contains no new commitments and no revisions to existing commitments.

I declare under penalty of perjury that the foregoing is true and correct. Executed on October 30, 2006.

Site Vice-President, Palisades Nuclear Plant Nuclear Management Company, LLC Enclosures (2) cc: Administrator, Region Ill, USNRC Project Manager, Palisades, USNRC Resident Inspector, Palisades, USNRC 27780 Blue Star Memorial Highway Covert, Michigan 49043-9530 Telephone: 269.764.2000

ENCLOSURE 1 RESPONSE TO RAI ON TSP AMENDMENT PALISADES NUCLEAR PLANT NRC Request

1. In your response to NRC Request 2 (contained on page 1 1 or 13 of your July 7, 2006 letter to the NRC), you describe your plans to manually connect the NaOH injection system to the containment spray flow pathway following a LOCA. 10 CFR 50.34(f)(Z)(vii) (and the criteria in Section 11.8.2 of NUREG-0737) states that, following an accident, the dose to a person accessing a vital area (an area which will or may require occupancy to aid in the mitigation or recovery from an accident) must not exceed the GDC 19 dose criterion of 5 rem whole body.

a. Provide plant layout drawings showing the path that an operator(s) would take to access the NaOH injection system, make the required hookups, initiate the injection of NaOH into the containment spray headers, and leave the area.

b. Provide the mission doses (including doses accrued during access and egress from the vital area) to the operator(s) who will manually connect and initiate the NaOH injection system following an accident. Verify that the operator(s) can perform this vital function without exceeding the 5 rem whole body dose limit at any of the various times (from 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> following loss of a fuel cladding barrier to seven days post-LOCA) that this operation may be performed following a LOCA.

c. If the manual connection of the NaOH injection system following an accident cannot be accomplished within the dose guidelines of GDC 19, then describe what measures you will take (such as use of additional shielding, use of multiple operators to break up the task of manually connecting the NaOH injection system, etc.) to ensure that the GDC 19 dose guidelines are not exceeded during performance of this action.

(8/11/2006)

NMC Response

1.

a. A time motion analysis of the NaOH addition mission has been performed.

The analysis, EA-EC976-01, "NaOH Addition Mission Dose," is provided as Enclosure 2. Plant layout drawings are provided in Attachment 1 of. The paths are indicated on mark-ups of plant drawings M-2 and M-3.

b. The mission dose to the operator has been determined in Enclosure 2.

The analysis concludes that a reasonable and conservative estimate of the maximum radiological dose received by a single individual performing the NaOH addition mission is less than the 5 rem TEDE limit. Therefore, measures such as the use of additional shielding or the use of multiple Page, 1 of 2

operators for various tasks do not need to be explicitly developed to ensure acceptable mission doses for all required personnel. Such measures would be employed by the emergency response organization as appropriate in keeping with the principles of ALARA and the protection of the health and safety of the public.

Page 2 of 2

ENCLOSURE 2 EA-EC976-01, "NaOH Addition Mission Dose" 24 Pages Follow

Obiective "KC>

Commitfed to Nuclear ~xce//ence This calculation provides a reasonable and conservative estimate of the radiological dose to a single individual performing the NaOH addition mission. The mission is to add the required quantity of NaOH to the containment spray system following a loss of coolant accident (LOCA) that progresses to the recirculation mode of emergency core cooling system (ECCS) operation in the event that no buffering agent (e.g., TSP) exists in containment. The calculation consists of a time-motion analysis of all required tasks that comprise the mission.

The estimate of total mission dose is compared to an acceptance criterion derived from Title 10 of the Code of Federal Regulations and Item ll.B.2 of the Clarification of TMI Action Plan Requirements, and is used to determine whether measures such as the use of additional shielding or the use of multiple operators for various tasks need to be developed to ensure acceptable mission doses for all required personnel.

Title:

NaOH Addition Mission Dose Approval:

See signature page EA-EC976-10 This calculation supports engineering change EC-976, which is being implemented to remove tri-sodium phosphate (TSP) from containment in order to address the potential for sump blockage due to chemical reaction products in post-accident sump water containing TSP and calcium-silicate (Cal-Sil) insulation. EC-976 contains provisions for the addition of an alternate buffer within 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> post-LOCA with recirculation, which requires entry into Room 121.

Revision: 0 Conclusions Date: 10/24/2006 Total Number of Pages: 24 A reasonable and conservative estimate of the maximum radiological dose received by single individual performing the NaOH addition mission is 4.1 13 rem TEDE. The estimate of total mission dose is less than the 5 rem TEDE limit. Therefore, measures such as the use of.additional shielding or the use of multiple operators for various tasks do not need to be explicitly developed a priori to ensure acceptable mission doses for all required personnel. Such measures will be employed by the emergency response organization as appropriate in keeping with the principles of ALARA and the protection of the health and safety of the public.

Table of Contents N

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Gmmmw bNuo*uEr-w 1.0 PURPOSE............................................................................................................................ 3 2.0 METHODOLOGY 3

2.1 Background.......................................................................................................................

3 2.2 Post-Accident Radiation Field Analysis 4

2.3 NaOH Addition Mission Time-Motion Analysis..................................................................

4 2.4 Software Codes................................................................................................................. 5 3.0 ACCEPTANCE CRITERIA 5

4.0 INPUTS.................................................................................................................................

6

5.0 REFERENCES

7 6.0 ASSUMPTIONS.................................................................................................................... 8 6.1 Verified Assumptions........................................................................................................

8 6.2 Unverified Assumptions..................................................................................................

11 7.0 ANALYSIS 11 7.1 Post-Accident Radiation Field Analysis...........................................................................

12 7.2 NaOH Addition Mission Time-Motion Analysis................................................................ 16 7.3 Results 17

8.0 CONCLUSION

S.................................................................................................................

17 9.0 ATTACHMENTS 17 EA-EC976-10 Revision 0 Page2of 17

1.0 PURPOSE NM?

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This calculation provides a reasonable and conservative estimate of the radiological dose to a single individual performing the NaOH addition mission. The mission is to add the required quantity of NaOH to the containment spray system following a loss of coolant accident (LOCA) that progresses to the recirculation mode of emergency core cooling system (ECCS) operation in the event that no buffering agent (e.g., TSP) exists in containment. The calculation consists of a time-motion analysis of all required tasks that comprise the mission.

EA-EC976-10 Revision 0 Page 3 of 17 The estimate of total mission dose is compared to an acceptance criterion derived from Title 10 of the Code of Federal Regulations (Ref. [I]) and Item ll.B.2 of the Clarification of TMI Action Plan Requirements (Ref. [18]), and is used to determine whether measures such as the use of additional shielding or the use of multiple operators for various tasks need to be developed to ensure acceptable mission doses for all required personnel.

This calculation supports engineering change EC-976 (Ref. [2]), which is being implemented to remove tri-sodium phosphate (TSP) from containment in order to address the potential for sump blockage due to chemical reaction products in post-accident sump water containing TSP and calcium-silicate (Cal-Sil) insulation. EC-976 contains provisions for the addition of an alternate buffer within 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> post-LOCA with recirculation, which requires entry into Room 121.

2.0 METHODOLOGY

2.1 Background

The purpose of TSP in containment is to control post-accident sump fluid pH to within the range 7-8. Ensuring post-accident sump pH between 7 and 8 assures that hydrogen generation, corrosion, insulation and debris dissolution, and radio-iodine retention are all acceptable and consistent with licensing basis assumptions. TSP removal is being pursued to mitigate the potential for containment sump screen blockage during the post-accident recirculation mode. By removing the TSP, reaction with dissolved calcium-silicate (Cal-Sil) insulation in the post-accident environment and subsequent precipitation is precluded. With the elimination of TSPICal-Sil precipitate, the predicted magnitude of sump screen blockage is reduced. This alleviates a specific NRC concern resulting from the integrated chemical effects testing performed in September 2005 (Ref. [3]).

However, the removal of TSP has the potential to impact post-accident sump pH which subsequently impacts iodine retention in sump water and can impact on-site and off-site doses. The impact on the radiological design basis due to the removal of TSP is evaluated in EA-EC-976-01 (Ref. [4]). This new calculation, EA-EC976-10, reasonably and conservatively determines the radiological dose to single individual performing the NaOH addition mission.

2.2 Post-Accident Radiation Field Analysis NM?

cam,,,imd bNuoLwuGnhnn A design review of post-accident operator actions was performed in response to NUREG-0737, Item ll.B.2 (Ref. [5]).

As part of this analysis, maximum post-accident dose rates for all areas that require access for the NaOH addition mission were determined. The analysis relies on source terms based on Regulatory Guide 1.4 (Ref. [6]) that can be characterized as TID-14844 (Ref. [7]) source terms.

EA-EC976-10 Revision 0 Page 4 of 17 Since these source terms credit iodine spray removal and do not consider the possibility of an un-buffered containment sump with subsequent re-volatilization and evolution of iodine, the radiation fields determined in these calculations are adjusted to conservatively account for the condition of complete loss of sump pH control.

First, an examination of the details of the source terms used for the NUREG-0737 response is performed. Then, the impact of the loss of sump pH control is determined and adjustments made to the radiation fields such that they are applicable to the un-buffered sump configuration.

The NUREG-0737 response considered dose from the following sources:

Shine from ECCS piping outside containment Shine from airborne activity inside containment through the containment wall Shine from airborne activity inside containment through penetrations Sources not considered are:

Immersion and inhalation doses due to entering room containing containment atmosphere leakage or ECCS recirculation water leakage Based on the expected conservative design of the modification, there is a low potential for the NaOH injection process (after multiple failures) to lead to filling the sensing line with ECCS recirculation water and/or potentially leaking, therefore the sensing line and sensing line leakage dose is excluded. Liquid or airborne leakage into rooms requiring access for the NaOH addition mission are not considered since leakage into these rooms is not expected, based on the barriers between the rooms and other ECCS recirculation piping and containment penetrations.

The radiation fields are combined with mission task information (see Section 2.3) and used to determine mission doses relative to the acceptance criterion (see Section 3.0).

2.3 NaOH Addition Mission Time-Motion Analysis The addition of NaOH to the primary coolant system to ultimately buffer the pH of the re-circulating sump fluid is controlled by Palisades emergency operations procedure EOP Supplement 42 (Ref. [8]), which defines pre-and post-RAS actions.

Each required task from this procedure is identified and associated with a specific plant location. Estimates of the time required for each task have been obtained from an operations crew (Ref. [9]). These estimates were derived from an in-plant walk-

down of the procedure with simulations of task performance where possible.

NM-Commmlted

%.-Ern-2.4 Software Codes EA-EC976-10 Revision 0 Page 5 of 17 No shielding calculations are performed for this analysis. Adjustments to the results from previous analyses are calculated with spreadsheets. The previous analyses relied upon QAD P-52 code for shielding calculations.

2.4.1 MicrosoftTM Excel The commercial spreadsheet application is used for source term computations and to compute the final integrated dose.

3.0 ACCEPTANCE CRITERIA The calculation of post-accident mission doses was required to respond to NUREG-0737 ll.B.2 concerning post-accident operator doses. Given the large degree of uncertainty associated with severe accident magnitude and progression, and uncertainty with the timing and duration of the alternate buffer addition mission activities, the specific acceptance criteria cited below are meant to provide confidence that mission activities can be completed safely with regard to personnel dose.

Sound radiation protection principles and the principle of "As Low As is Reasonably Achievable" are applicable to the NaOH mission irrespective of the demonstration of an acceptable single individual dose as per the criterion below. In any actual event, measures such as the use of additional shielding or the use of multiple operators for various tasks are available to emergency response organization personnel. However, the demonstration of an acceptable single individual dose obviates the need to formally develop such measures prior to the occurrence of the event.

Limits for personnel performing the alternate buffer addition mission are derived from 10-CFR-20, Subpart C (20.1 201 (a)(l)(i)), 10-CFR-50, Section 50.34(f)(2)(vii) and NUREG-0737 Item ll.B.2.

All doses considered in this calculation are external whole body gamma doses. As such, the deep dose equivalent (DDE) typically calculated in shielding codes is equivalent to the TEDE.

The acceptance criterion is as follows:

A reasonable and conservative estimate of the radiological dose to a single individual performing the NaOH addition mission following a LOCA with recirculation shall be less than 5 rem TEDE.

It is noted that this acceptance criterion is only '/i of the EPA-400 guidance of 10 rem for workers performing emergency services to protect valuable property (Ref. [ I 71).

Therefore, the acceptance criterion above ensures that the EPA-400 limit can be met for an individual performing the mission whose cumulative annual dose is at the 5 rem TEDE limit at the time of the event.

4.0 INPUTS N

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Comm,l*d a Nus*erErb 4.1 NUREG-0737 response dose rates calculated for points inside the iso-dose-rate lines should be added to the dose rate from containment shine within the iso-dose-rate lines.

EA-EC976-10 Revision 0 Page 6 of 17 Source: NUREG-0373 response (Ref. [5]), Figure 19, Note 1 4.2 NUREG-0737 response dose rates from different source locations at the same dose point should be added to determine the total dose rate.

Source: NUREG-0373 response (Ref. [5]), Figure 19, Note 1 4.3 Dose rates and source term type from the following NUREG-0737 response calculations are:

Source: NUREG-0373 response (Ref. [5]), Table 6, Figures 19 and 22.

Calculation 570-13 570-15 570-23 590-4 602-5 602-9 602-1 0 602-1 1 602-1 3 602-1 4 Dose Rate (mremlhr)

Source Type Liquid 5.0 x 1 o2 2.2 x 1 o4 1. 3 ~

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7 for time periods on the order of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in the absence of pH control additives such as TSP (Ref. [ I 01). Additionally, regardless of the initial pH or the presence of TSP, the pH of the sump water is expected to rise to about 7, primarily because Cal-Sil contains sodium silicate as an impurity (Ref. [ I I]). The sodium silicate is very soluble and as it dissolves the dissolved sodium (Na) causes the pH of the initial boric acid/LiOH solution to increase. Moreover, Palisades specific testing indicates that post-accident sump water pH would be increased by the dissolved Cal-Sil (Ref. [12]). In addition, the NaOH mission itself is designed to restore sump pH control prior to 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> after a LOCA with recirculation. The partial control of sump pH during the injection mission would be beneficial with regard to

' mission dose. However, no credit for these phenomena will be taken in determining NaOH mission dose.

The assumed complete loss of sump pH control impacts the containment atmosphere halogen chemical form distribution, since re-evolved iodine is

preferentially elemental. However, since the spray removal process modeled in Reference [5] does not differentiate between chemical forms, this phenomenon has no impact on calculated dose rates.

NM-cammaw loNudwEr&&+za The assumed loss of sump pH control impacts iodine scrubbing of the containment atmosphere. Re-evolution of iodine limits the effectiveness of the containment sprays since long-term retention of halogens cannot be assured.

Therefore, the assumed loss of sump pH control is assumed to result in no removal of halogens from the containment atmosphere. This results in the initial 50% halogen release to containment remaining in the containment atmosphere.

EA-EC976-10 Revision 0 Page 13 of 17 Loss of sump pH control impacts retention of iodine in the sump. Re-evolution will occur in containment and could occur after transport outside of containment. Re-evolution in containment will reduce the iodine in the liquid source term. However, no credit is taken for a reduction in liquid halogen source term that would result if complete re-evolution were to occur. For conservatism, the liquid source term is assumed to be unaffected by the loss of sump pH control.

Therefore, the impact of the assumed complete loss of sump pH control on the Reference [5] source terms is a reduction in halogen inventory for liquid source terms (conservatively not credited) and an increase from 25% to 50% of core halogen inventory for gaseous source terms.

7.1.3 Impact of TSP Removal on NUREG-0737 R ~ S D O ~ S ~

Radiation Fields No adjustment to the radiation fields from liquid source terms is needed since the liquid source terms bound the condition of TSP removal and are not altered as discussed above. To account for the impact of the altered gaseous source term on the dose rates calculated in Reference [5], the gaseous source term dose rates are increased by 50%. The component of the dose rate due to halogens is estimated by determining the ratio of the total activity-energy of the halogens to the total halogen and non-halogen source term. This calculation is performed in and it is seen that the halogens contribute an estimated 44.3% to the total dose rate. For conservatism, this estimate is rounded up to 50%.

Therefore, the gaseous source term dose rates from Reference [5] are increased by 50% to conservatively account for the additional halogens present in the containment atmosphere when complete loss of sump pH control is assumed.

7.1.4 Mission Area Doses N

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Mission Area 1 EA-EC976-10 Revision 0 Page 14 of 17 From Figure 22 of Reference [5], a representative dose rate for mission area 1 is 26 rnremlhr, based on dose point 61 1-1 2. Point 61 1-1 2 is near coordinate line 26 in the El. 61 1 ' corridor. This point is closer to containment than the caustic tanklchemistry lab area and represents a conservative shine geometry through the personnel air lock penetration. This dose point can be used as a conservative surrogate for the dose in mission area 1. Since there is only a single calculation for this point and it is outside the iso-dose-rate lines the contribution of containment shine and other dose calculations should not be separately added.

Since the dose is due to a gaseous source term, the dose rate is increased by 50% to 39 mremlhr to account for TSP removal.

Mission Area 2 From Figure 22 of Reference [5], a representative dose rate for mission area 2 is 50 mremlhr, based on dose points 61 1-1 1 and 61 1-1 2. These points are closer to containment than the most of the corridor area and represent a conservative shine geometry through the personnel air lock penetration. The maximum of these dose points can be used as a conservative surrogate for the dose in mission area 2. Since there are only single calculations for these points and both are outside the iso-dose-rate lines the contribution of containment shine and other dose calculations should not be separately added. Points 61 1-7 and 570-1 5 are in the stairwell and are included in mission area 3. Point 61 1-8 is significantly higher than 50 mremlhr (770 mremlhr) but represents a small area of the corridor in which only a very small fraction of the time is estimated to be spent relative to the time in other parts of mission area 2. Since the dose is due to a gaseous source term, the dose rate is increased by 50% to 75 mremlhr to account for TSP removal.

Mission Area 3 From Figure 22 of Reference [5], a representative dose rate for mission area 3 is 10,000 mremlhr, based on dose points 570-1 5, 61 1-5, 61 1-6 and 61 1-7. Doses for these points range from 500 mremlhr to 90,000 rnremlhr. 10,000 mremlhr is chosen as representative even though dose rates as high as 90,000 mremlhr may exist in localized areas due to containment shine through the personnel air lock. The 10,000 mremlhr value can be used as a reasonable surrogate for the average dose considering: (1) doses in the stairwell behind the shield wall would be orders of magnitude lower, (2) once descended lower than the 61 1 ' elevation, the flooring provides significant additional shielding, and (3) the overall mission time in area 3 (2 minutes) is very conservative (an actual traverse would only take a few tens of seconds). Since there are only single calculations for these points and both are outside the iso-dose-rate lines the contribution of containment shine and other dose calculations should not be separately added. Since the limiting doses are due to a gaseous source term, the dose rate is increased by 50% to 15,000 mremlhr to account for TSP removal.

Mission Area 4 Comm,m k7 NudwiEmXM From Figure 19 of Reference [5], a representative dose rate for mission area 4 is 3,300 rnremlhr, based on dose points 570-1 3, 602-1 1, 602-1 3, and 602-1 4.

Doses for these points range from c1 mremlhr to 3,300 rnremlhr. The maximum value can be used as a conservative surrogate for the dose in mission area 4.

Since there are only single calculations for these points and both are outside the iso-dose-rate lines the contribution of containment shine and other dose calculations should not be separately added. Since the limiting doses are due to a liquid source term, the dose rate bounds TSP removal and is not increased.

EA-EC976-10 Revision 0 Page 15 of 17 Mission Area 5 From Figure 19 of Reference [5], a representative dose rate for mission area 5 is 10 rnremlhr, based on dose points 602-9 and 602-1 0. Doses for these points are all c1 mremlhr. The 10 mremlhr value can be used as a conservative surrogate for the dose in mission area 5. Since there are only single calculations for these points and both are outside the iso-dose-rate lines the contribution of containment shine and other dose calculations should not be separately added. Since the dose is due to a gaseous source term, the dose rate is increased by 50% to 15 mremlhr to account for TSP removal.

Mission Area 6 From Figure 19 of Reference [5], a representative dose rate for mission area 6 is 10,000 rnremlhr, based on dose points from mission areas 5 and 7. There are no dose rates available for this mission area but rates can be expected to be between those of mission areas 5 and 7. The 10,000 mremlhr value can be used as a conservative surrogate for the dose in mission area 6, given the shielding and distance differences from mission areas 5 and 7. Since the majority of the dose is due to a liquid source term (as estimated from mission area 7), the dose rate bounds TSP removal and is not increased.

Mission Area 7 From Figure 19 of Reference [5], a representative dose rate for mission area 7 is 35,000 rnremlhr, based on dose points 570-23, 590-4, and 602-5. Doses for these points sum to 35,000 mremlhr and the value can be used as a conservative surrogate for the dose in mission area 7. Since there are multiple calculations for these points the doses are added. Since the points are outside the iso-dose-rate lines the contribution of containment shine should not be separately added. Note that this value is consistent with the value quoted for this area in item b) on page 12 of Reference [5]. Since the limiting doses are due to a liquid source term, the dose rate bounds TSP removal and is not increased.

Adjusted post-accident dose rates for mission areas are summarized in.

7.2 NaOH Addition Mission Time-Motion Analysis N

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Commrlrsd rn N u d r u r E r w The addition of NaOH to the primary coolant system to ultimately buffer the pH of the re-circulating sump fluid is controlled by Palisades emergency operations procedure EOP Supplement 42 (Ref. [8]), which defines pre-and post-RAS actions. Section 5 of EOP Supplement 42 contains the steps required to perform the NaOH addition:

EA-EC976-10 Revision 0 Page 16 of 17 Step 5.1 does not contain actions but lists required equipment and locations.

Step 5.2 is to fill caustic addition tank M-66 with 25% NaOH solution. Both the tank and NaOH are in mission area 1 and the task is estimated to take 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.

Step 5.3 is to notify the control room that various fire doors will be blocked open and can be performed from mission area 1 by companion phone in 2 minutes.

Step 5.4 is to place the portable injection pump near tank M-66 and is performed in mission area 1 in 2 minutes.

Step 5.5 is to connect the hose to the suction of portable injection suction and is performed in mission area 1 in 5 minutes.

Step 5.6 is to route the suction hose to the caustic tank and is performed in mission area 1 in 2 minutes.

Step 5.7 is to assemble the discharge hose segments and is performed in mission area 1 in 10 minutes, mission area 2 in 15 minutes, and in mission areas 3, 4, 5, and 6 in a total of 11 minutes.

Step 5.8 is to identify the in-service containment spray header and can be performed in a low dose pre-job brief area. It is therefore not included in the mission dose.

Step 5.9 or 5.10 is to prepare either flow transmitter FT-0301 or FT-0302 for injection by closing the isolation valves, opening the bypass valve, removing the check valve plug, and installing the discharge hose onto the check valve.

This is performed in mission area 7 in 5 minutes.

Step 5.1 1 is to connect suction hose to desired suction drain and is performed in mission area 1 in 10 minutes.

Step 5.12 is to provide power to the portable injection pump and is performed primarily in mission area 1 (or lower dose areas) in 20 minutes. Verification of breaker 52-855 is in mission area 7 and has been included in the 5 minutes of Steps 5.9 and 5.1 0. Note that access to the 590' elevation is needed to complete power cable connection and this has been included in the times for Step 5.7.

Steps 5.13, 5.14 and 5.15 are to ensure proper valve alignment and are performed in mission area 1 in 2 minutes.

Step 5.16 is to vent the injection pump and is performed in mission area 1 in 5 minutes.

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1. e Step 5.1 7 is to perform the NaOH injection and is performed in mission area 1 in 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />.

EA-EC976-10 Revision 0 Page 17 of 17 The remaining steps are for flushing and disassembling the injection system and are not required to achieve sump pH buffering. These activities are not time critical and can be performed by other personnel as needed.

The time estimates for each task above have been obtained from an operations crew and were derived from a procedure walk-down with simulations of task performance where possible. The time estimates are summarized in Attachment 5.

The radiation fields are combined with mission task information (time and location) to determine mission doses relative to the dose acceptance criterion in Attachment 5.

7.3 Results See Attachment 5.

8.0 CONCLUSION

S A reasonable and conservative estimate of the maximum radiological dose received by single individual performing the NaOH addition mission is 4.1 13 rem TEDE. The estimate of total mission dose is less than the 5 rem TEDE limit. Therefore, measures such as the use of additional shielding or the use of multiple operators for various tasks do not need to be explicitly developed a priori to ensure acceptable mission doses for all required personnel. Such measures will be employed by the emergency response organization as appropriate in keeping with the principles of ALARA and the protection of the health and safety of the public.

9.0 ATTACHMENTS : NaOH Mission Path (2 pages) : Core Inventory ( I page) : Liquid Source Terms (1 page) : Gaseous Source Terms (2 pages) : Results (1 page)

EA-EC976-10 Revision 0 Page 1 of 1 Nuclide

[ID-Mass#]

Br-84 Br-85 Kr-83m Kr-85m Kr-85 Kr-87 Kr-88 Rb-88 Sr-89 Sr-90 Sr-91 Sr-92 Y-90 Y-91 Mo-99 Ru-1 06 1-1 31 1-1 32 1-1 33 1-1 34 1-1 35 Xe-131 m Xe-l33m Xe-133 Xe-l35m Xe-135 Xe-138 Cs-134 CS-1 36 CS-1 37 CS-1 38 Ba-l37m Ba-140 La-1 40 Ce-144 Atomic No.

[Atomic#]

35 35 36 36 36 36 36 37 38 38 38 38 39 39 42 44 53 53 53 53 53 54 54 54 54 54 54 55 55 55 55 56 56 57 58 Mass No.

[Mass#]

84 85 83 85 85 87 88 88 89 90 9 1 92 90 9 1 99 106 131 132 133 134 135 131 133 133 135 135 138 1 34 136 137 138 137 140 1 40 1 44 NUREG-0737 Activity

[Cil 1.60E+07 2.23E+07 9.50E+06 2.23E+07 5.1 3E+05 4.07E+07 5.71 E+07 5.75E+07 7.56E+07 3.85E+06 9.89E+07 9.76E+07 3.83E+06 1.00E+08 1.33E+08 2.40E+07 7.69E+07 8.92E+07 1.31 E+08 1.66E+08 1.31 E+08 4.59E+05 3.15E+06 1.31 E+08 3.34E+07 1.96E+07 1.21 E+08 1.34E+06 8.79E+05 4.91 E+06 1.28E+08 4.60E+06 1.30E+08 1.31 E+08 7.43E+07

Nuclide

[ID-Mass#]

Br-84 Br-85 Kr-83m Kr-85m Kr-85 Kr-87 Kr-88 Rb-88 Sr-89 Sr-90 Sr-91 Sr-92 Y-90 Y-91 Mo-99 Ru-1 06 1-1 31 1-1 32 1-1 33 1-1 34 1-1 35 Xe-131 m Xe-l33m Xe-133 Xe-l35m Xe-135 Xe-138 Cs-134 CS-1 36 Cs-137 CS-1 38 Ba-l37m Ba-140 La-1 40 Ce-144 Liquid Release Fraction

[unitless]

0.50 0.50 1.oo 1.oo 1.oo 1.oo 1.oo 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.50 0.50 0.50 0.50 0.50 1.oo 1.oo 1.oo 1.oo 1.oo 1.oo 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 (PCS Volume:

7,800 EA-EC976-10 Revision 0 Page 1 of 1

Nuclide

[I D-Mass#]

Br-84 Br-85 Kr-83m Kr-85m Kr-85 Kr-87 Kr-88 Rb-88 Sr-89 Sr-90 Sr-91 Sr-92 Y-90 Y-91 Mo-99 Ru-1 06 1-1 31 1-1 32 1-1 33 1-1 34 1-1 35 Xe-131 m Xe-l33m Xe-133 Xe-l35m Xe-135 Xe-138 Gaseous Release Fraction

[unitless]

0.25 0.25 1.oo 1.oo 1.oo 1.oo 1.oo 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.25 0.25 0.25 0.25 0.25 1.oo 1.oo 1.oo 1.oo 1.oo 1.oo NUREG-0737 Source Term

[pCi/cc]

8.61 E+01 1.20E+02 2.05E+02 4.80E+02 1.1 0E+01 8.76E+02 1.23E+03 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 4.14E+02 4.80E+02 7.05E+02 8.94E+02 7.05E+02 9.88E+00 6.78E+01 2.82E+03 7.1 9E+02 4.22E+02 2.61 E+03 EA-EC976-10 Revision 0 Page 1 of 2

Nuclide

[I D-Mass#]

Cs-134 CS-1 36 Cs-137 CS-1 38 Ba-l37m Ba-1 40 La-1 40 Ce-144 Gaseous Release Fraction

[unitless]

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 NUREG-0737 Source Term

[yCi/cc]

0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 (Containment Net Free Volume:

1,640,000 Total Activity-Energy:

1.1 9E+04 Halogen Activity-Energy:

5.29E+03 Halogen Fraction:

0.4430 EA-EC976-10 Revision 0 Page 2 of 2

Estimated Maximum NaOH Addition Mission Dose

@ 1 Hour Post-LOCA during Recirculation with 100% Fuel Melt and No Sump pH Control Task (description)

EOP Supplement 42 Location (step)

(description)

Time at Raw No Buffer Total Location Dose Rate Dose Rate Dose (min)

(Rlhr)

(Rlhr)

(rem TEDE)

Fill caustic tank, notify control room, place injection pump, connect suction hose to pump, route suction hose, assemble discharge hose, connect 5-2, 5-3, 5-4, 5-5, 5-6, 5-discharge hose to pump, connect 7, 5-1 1, 5-1 2, 5-13, 5-El. 61 1 - near caustic tank M-66 and chemistry hot lab suction hose to tank, align breakers, 358 0.026 0.039 0.233 route power cord, connect power 14, 5-1 5, 5-1 6, 5-1 7 cord, align breakers, perform line-up verification, vent pump suction, inject NaOH Assembly discharge hose, route discharge hose 5-7 Route discharge hose, route power cord*

5-7 Route discharge hose, route power cord*

5-7 Route discharge hose, route power cord*

5-7, 5-12 Route discharge hose 5-7 Route discharge hose, close isolation valves, open bypass valve, remove valve plug, connect discharge hose, 5-7, 5-9, 5-1 0 open isolation valves "power cord routing requires acess to El. 590' El. 61 1 -corridor to stairwell El. 61 1 -stairwell*

El. 590 - stairwell El. 590 -corridor to jib crane El. 590 -jib crane room El. 590 -west end of C-40 panel room Mission Time:

6.483 hours0.00559 days <br />0.134 hours <br />7.986111e-4 weeks <br />1.837815e-4 months <br /> Mission Dose:

4.113 rem TEDE EA-EC976-I 0 Revision 0 Page 1 of I