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Proposed Revised Tech Specs Re Operation of Purge & Vent Valves
	ML20114B398
Person / Time
Site:	Vermont Yankee
Issue date:	01/15/1985
From:	; VERMONT YANKEE NUCLEAR POWER CORP.
To:	;
Shared Package
ML20114B397	List: ML20114B396; ML20114B398;
References
	NUDOCS 8501290138
	Download: ML20114B398 (7)
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VYNPS ,

3.6 LIMITING CONDITIONS FOR OPERATION 4.6 SURVEILLANCE REQUIREMENTS 3.6 REACTOR COOLANT SYSTEM 4.6 REACTOR COOLANT SYSTEM Specification:

A. Pressure and Temperature Limitations (cont.)

5. The reactor vessel irradiation surveillance specimens shall be removed and examined to determine changes in material properties in accordance with the following schedule:

CAPSULE REMOVAL YEAR 1 10 2 30 3 Standby The results shall be used to update Figures 3.6.2 and 3.6.3. The removal times shall be referenced to the refueling outage following the year

,- specified, referenced to the date of commercial operation.

B. Coolant Chemistry B. Coolant Chemistry

1. a. During reactor power operation, the 1. a. A sample of reactor coolant shall radioiodine concentration in the be taken at least every 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months reactor coolant shall not exceed and analyzed for radioactive 1.1 microcuries of I-131 dose iodines of I-131 through I-135 equivalent per gram of water, during power operation. In except as allowed in addition, when steam jet air Specification 3.6.B.1.b. ejector monitors indicate an increase in radioactive gaseous effluents of 25 percent or 5000 uCi/sec, whichever is greater.

8501:?90138 Gl!H)115 l Amendment No. 33 PDR ADOCK 05000271 P PDR 106

VYNPS 3.6 LIMITING CONDITIONS FOR OPERATION 4.6 SURVEILLANCE REQUIREMENTS a

3.6 REACTOR COOLANT SYSTEM 4.6 REACTOR COOLANT SYSTEM B. Coolant Chemistry (cont'd) B. Conlant Chemistry (cuat'd)

1. a. during steady state reactor operation a reactor coolant sample shall be taken and analyzed for radioactive iodines,

b. The radiolodit.e concer.tration in b. An isotopic analysis of a reactor the reactor coolant shall not coolant sample shall be made at exceed 1.1 microcuries of I-131 least once per month.

dose equivalent per gram of water, for greater than 24 consecutive hours,

c. The radiciodine concentration in c. Whenever the radioiodine the reactor coolant shall'not concentration of prior steady-state exceed 4.0 microcuries of I-131 reactor operation is greater than dose equivalent per gram of water. 0.011 uCi/gm but less than 0.11 juCi/gm, a sample of reactor coolant shall be taken within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of the next reactor startup and

.- analyzed for radioactive iodines of I-131 through I-135.

d. Whenever the radioiodine concentration of prior steady-state reactor operation is greater than 0.11 pCL/gm, a sample of reactor coolant shall be taken prior to the Amendment No. 33 106a l

P-~ z/. T VYNPS 3.6 LIMITING CONDITIONS FOR OPERATION 4.6 SURVEILLANCE REQUIREMENTS-3.6 REACTOR COOLANT SYSTEM 4.6 REACTOR COOLANT SYSTEM B. Coolant Chemistry (cont'd) B. Coolant Chemistry (cont'd)

1. d. next reactor startup and analyzed (cont'd) for radioactive iodines of I-131 through I-135, as well as within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months following a reactor startup. l

e. With the radiciodine concentration in the reactor coolant greater than 1.1 microcuries/ gram dose equivalent I-131, a sample of reactor coolant shall be taken every 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months and analyzed for radioactive iodines of I-131 through I-135, until the specific activity of the reactor coolant is restored below 1.1 microcuries/ gram dose equivalent I-131.

2. The reactor coolant water shall not 2. During startups and at steaming rates exceed the following limits with below 100,000 pounds per hour, a sample steaming rates less than 100,000 pounds of reactor coolant shall be taken every per hour except as specified in ~

four hours and analyzed for conductivity Specification 3.6.B.3: and chloride content.

Conductivity Sumho/cm Chloride ion ,0.1 ppm

3. For reactor startups the maximum value 3. a. With steaming rates greater than or for conductivity shall not exceed 10 equal to 100,000 pounds per hour, a umho/cm and the maximum value for reactor coolant sample shall be chloride ion concentration shall not Amendment No. 107

.. __ s . . . _ _ . .

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VYMPS 3.6 LIMITING CONDITIONS FOR OPERATION 4.6- SURVEILLANCE REQUIREMENTS I

3.6 REACTOR COOLANT SYSTEM i 4.6 REACTOR COOLANT SYSTEM l

-B. Coolant Chemistry (cont'd) B. Coolant Chemistry (cont'd)

3. exceed 0.1 ppm, in the reactor coolant 3. a. taken at least every 96 hours0.00111 days 0.0267 hours 1.587302e-4 weeks 3.6528e-5 months and (cont'd) water for the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months after (cont'd) when the continuous conductivity placing the reactor in the power monitors indicate abnormal operating condition. conductivity (other than short-term spikes), and analyzed for conductivity and chloride ion content.

b. When the continuous conductivity monitor is inoperable, a reactor coolant sample shall be taken every four hours and analyzed for conductivity and chloride ion content.

4. Except'as specified in Specification 3.6.B.3'above, the reactor coolant water shall not exceed the following limits with steaming rates greater than or equal to 100,000 pounds per hours.

Conductivity 5 uhmo/cm

. Chloride ion 0.5 ppm

5. If Specification 3.6.B. is not met, an orderly shutdown shall be intitiated and the reactor shall be in the cold shutdown condition within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

Amendment No. 107a

_ ~

7-VYNPS 3.6 & 4.6 (cont'd) calculated on the basis of the radiciodine concentration limit of 1.1 uCi of I-131 dose equivalent per gram of water, atmospheric diffusion from an equivalent elevated release of 10 meters at the nearest cite boundary (190 m) for a X/Q = 3.9 x 10-3 sec/m3 (Pasquill D and.0.33 m/sec equivalent), and a steam line isolation valve closure time of five seconds with a steam / water mass release of 30,000 pounds.

The iodine spike limit of four (4) microcuries of I-131 dose equivalent per gram of water provides an iodine peak or spike limit for the reactor coolant concentration to assure that the radiological consequences of a postulate LOCA are within 10CFR part 100 dose guidelines.

The reactor coolant sample will be used to assure that the limit of Specification 3.6.B.1 is not exceeded. The radioiodine concentration would not be expected to change rapidly during steady-state operation over a period of 96 hours0.00111 days 0.0267 hours 1.587302e-4 weeks 3.6528e-5 months . In addition, the trend of the radioactive gaseous effluents, which is continuously monitored, is a good indicator of the trend of the radiolodine concentration in the reactor coolant. When a significant increase in radioactive gaseous effluents is indicated, as specified, an additional reactor coolant sample shall be taken and analyzed for radioactive iodine.

Whenever an isotopic analysis is performed, a reasonable effort will be made to determine a significant percentage of those contributors representing the total radioactivity in the reactor coolant sample. Usually at least 80 percent of the total gamma radioactivity can be identified by the isotopic analysis.

It has been observed that radioiodine concentration can change rapidly in the reactor coolant during transient reactor operations, such as reactor shutdown, reactor power changes, and reactor startup if failed fuel is present. As specified, additional reactor coolant samples shall be taken and analyzed for reactor operations in which steady-state radioiodine concentrations in the reactor coolant indicate various levels of iodine releases

'from the fuel. Since the radiciodine concentration in the reactor coolant is not continuously measured, reactor coolant sampling would be ineffective as a means to rapidly detect gross fuel element failures. Itowever, some capability to detect gross fuel element failures is inherent in the radiation monitors in the off-gas system on the main steam line.

Materials in the primary system are primarily 304 stainless steel and Zircaloy. The reactor water chemistry limits are established to prevent damage to these materials. The limit placed on chloride concentration is to prevent stress corrosion cracking of the stainless steel.

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VYNPS

TABLE 4.7.2.a PRIMARY CONTAINMENT ISOLATION VALVES VALVES SUBJECT TO TYPE C LEAKACK TESTS Number of Power Maximum Action on Icolation Operated valves Operating Normal Initiating Group Valve Identification Inboard Outboard Time (sec) Position Signal 1 Main Steam Line Isolation (2-80A, D & 2-86A, D) 4 4 5(Note 2) Open GC 1 Main Steam Line Drain (2-74, 2-77) 1 2 35 Closed SC 1 Recirculation Loop Sample Line (2-39, 2-40) 1 1 5 Closed SC 2 RMR Discharge to Radwaste (10-57, 10-66) 2 25 Closed SC 2 Drywell Floor Drain (20-82, 20-83) 2 20 Open GC 2 Drywell Equipment Drain (20-94, 20-95) 2 20 Open CC 3 Drywell Air Purge Inlet (16-19-9) 1 10 Closed SC 3 Drywell Air Purge Inlet (16-19-8) 1 10 Open GC 3 Drywell Purge & Vent Outlet (16-19-7A) .

I 10 Closed

SC l 3 Drywell Purge & Vent Outlet Bypass (16-19-6A) 1 10 Closed SC 3 Drywell & Suppression Chamber Main Exhaust (16-19-7) 1 10 Closed

SC l 3 Suppression Chamber Purge Supply (16-19-10) 1 10 Closed SC 3 Suppression Chamber Purge & Vent Outlec (16-19-7B) 1 10 Closed SC 3 Suppression Chamber Purge & Vent Outlet Bypass (16-19-6B) 1 10 Open CC 3 Exhaust to Standby Cas Treatment System (16-19-6) 1 10 Open GC 3 Containment Purge Supply (16-19-23) 1 10 Open CC 3 Containment Purge Makeup (16-20-20, 16-20-22A, 16-20-22B) 3 NA Closed SC I 5 Reactor Cleanup System (12-15,12-18) 1 1 25 Open GC 5 Reactor Cleanup System (12-68) ,- 1 45 Open GC 6 HPCI (23-15, 23-16) 1 1 55 Open CC 6 RCIC (13-15, 13-16) 1 1 20 Open GC Primary / Secondary Vacuum Relief (16-19-11A, 16-19-11B) 2 NA Closed SC Primary / Secondary Vacuum Relief (16-19-12A, 16-19-12B) 2 NA Closed Process Control Rod Hydraulic Return Check Valve (3-181) NA Open Process 3- Containment Air Sampling (VG 23, VG 26, 109-76A&B) 4 5 Open CC e Velves 16-19-7 and 16-19-7A shall have stops installed to limit valve opening to 50 0 or less.

l AmendmerL No. 58, 61, 74 135

VYNPS Primary Containment Isolation Valves Those large pipes comprising a portion of the reactor coolant system whose failure could result in uncovering the reactor core are supplied with automatic isolation valves (except those lines needed for emergency core cooling system cperation or containment cooling). The closure times specified herein are adequate to prevent loss of more cooling from the circumferential rupture of any of these lines outside the containment than from a steam line rupture. There, this isolation valve closure time is sufficient to prevent uncovering the core.

Purge and vent valve testing performed by Allis-Chalmers has demonstrated that all butterfly purge and vent valves installed at Vermont Yankee can close from full open conditions at design basis containment pressure. However, as an cdditional conservative measure, limit stops have been added to valves 16-19-7/7A, limiting the opening of these valves to 500 open while operating, as requested by NRC in their letter of May 22, 1984. (NVY 84-108)

In order to assure that the doses that may result from a steam line break do not exceed the 10CFR100 guidelines, it is necessary that no fuel rod perforation resulting from the accident occur prior to closure of the main steam line isolation valves. Analyses indicate the fuel rod cladding perforations would be avoided for the main steam valve closure times, including instrument delay, as long as 10.5 seconds. The test closure time limit of five seconds for i

these main steam isolation valves provides sufficient margin to assure that cladding perforations are avoided and 10CFR100 limits are not exceeded. Redundant valves in each line insure that isolation will be effected applying the oingle failure criteria.

The main steam line isolation valves are functionally tested on a more frequent interval to establish a high degree of reliability.

The containment is penetrated by a large number of small diameter instrument lines. A program for periodic testing and examination of the flow check valves in these lines is performed _similar to that described in Amendment No. 23, Millstone Unit 1 Docket 50-245.

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ML20114B398

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