ML20210P288
| ML20210P288 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 05/07/1986 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20210P296 | List: |
| References | |
| TAC-59902, NUDOCS 8605130165 | |
| Download: ML20210P288 (2) | |
Text
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REACTOR COOLANT SYSTEM BASES Reducing T va to less than 500*F prevents the release of activity should a steam a
generator tu6e rupture since the saturation pressure of the primary coolant is The below the lift pressure of the atmospheric steam relief valves.
surveillance requirements provide adequate assurance that excessive specific activity levels in the primary coolant will be detected in sufficient ti.me to take corrective action.
Information obtained on iodine spiking will be used to
~ assess the parameters associated with spiking phenomena. A reduction in frequency of isotopic analyses following power changes may be permissible if justified by the data obtained.
3/4.4.10 PRESSURE / TEMPERATURE LIMITS The temperature and pressure changes during heatup and cooldown are limited to be consistent with the requirements given in the ASME Boiler and Pressure Vessel Code,Section III, Appendix G as required per 10CFR Part 50 Appendix G.
1)
The reactor coolant temperature and pressure and system heatup and cooldown rates (with the exception of the pressurizer) shall be limited in accordance with Figures 3.4-2 and 3.4-3 for the first full-power service period.
a) Allowable conbinations of pressure and temperature for specific tegerature change rates are below and to the right of the limit lines shown. Limit lines for cooldown rates between those presented may be obtained by interpolation.
b) Figures 3.4-2 and 3.4-3 define limits to assure prevention of nonductile f ailure only. For normal operation, other inherent plant characteristics, e.g., puq heat addition and pressurizer heater i
capacity, ney limit the heatup and cooldown rates that can be achieved over certain pressure-temperature ranges.
2)
These limit lines shall be calculated periodically using methods provided below.
3)
The secondary side of the steam generator must not be pressurized above 200 psig if the tegerature of the steam generator is below 70*F.
8605130165 860507 PDR ADOCK 05000364 P
PDR FARLEY-UNIT 2 B 3/4 4-6 AMENDMENT NO. 55
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{
BASES j
3/4.4.8 CHEMISTRY
}
i The limitations on Reactor Coolant System chemistry ensure that corrosion t
of the Reactor Coolant System is minimized and reduces the potential for Reactor i
Coolant System leakage or failure due to stress corrosion. Maintaining the
{
i chemistry within the Steady State Limits provides adequate corrosion protection l
~to_ ensure the structural integrity of the Reactor Coolant System over the life j
of the plant. The associated effects of exceeding the oxygen, chloride and l
6 fluoride limits are time and temperature dependent. Corrosion studies show that operation may be continued with contaminant concentration levels in excess of the Steady State Limits, up to the Transient Limits, for the specified limited time intervals without having a significant effect on the structural integrity, i
of the Reactor Coolant System. The time interval permitting continued operation
(
within the-restrictions of the Transient Limits provides time for taking i
corrective actions to restore the contaminant concentrations to within the Steady State Limits.
The surveillance requirements provide adequate assurance that concentrations in excess of the limits will be detected in sufficient time to take corrective action.
3/4.4.9 SPECIFIC ACTIVITY The limitations on the specific activity of the primary coolant ensure that the resulting 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> doses at the site boundary will not exceed an appropriately small fraction of Part 100 limits following a steam generator tube rupture accident in conjunction with an assumed steady state primary-to-secondary steam l
generator leakage rate of 1.0 GPM. The values for the limits on specific activity represent limits based upon a parametric evaluation by the NRC of typical site locations. These values are conservative in that specific site parameters of the Farley site, such as site boundary location and meteorological ccnditions, were not considered in this evaluation.
The ACTION statement permitting POWER OPERATION to continue for limited time periods with the primary coolant's specific activity greater than 1.0 microcuries/ gram DOSE EQUIVALENT I-131, but within the allowable limit shown on Figure 3.4-1, accommodates possible iodine spiking phenomenon which may occur following changes in THERMAL POWER.
1 FARLEY-UNIT 2 B 3/4 4-5 AMENDMENT NO. 54
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