Document: NUREG-0800
Document ID: 3b207b59-015a-4145-be01-1f474ceec289
Document Type: srp
Title: MAIN CONDENSER EVACUATION SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070590.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.4.2
CFR Part: 
CFR Title: 

Content:
al discharge path for radioactivity in BWRs during normal operation, including anticipated operational occurrences. For PWRs, radioactivity detected in this system is usually the first indication of a primary-to-secondary steam generator tube leak. Postulated accidents can result in fuel damage or failure, and the detectors installed in this system would serve to monitor such radioactivity in order to control and limit its release. Meeting the requirements of GDC 64 provides a level of assurance that effluents from the main condenser evacuation system are suitably monitored and controlled. 21 III. REVIEW PROCEDURES The ETSBSPLB reviewer will select and emphasize material from this SRP section as may be appropriate for a particular case. 1. In the ETSBSPLB review of the MCES, the P&IDs are reviewed to determine the flow paths of gases through the system, including all bypasses, and the points of release of gaseous wastes to the environment or other systems. This information is used in SRP Section 11.3 to calculate the quantity of radioactive material released annually in gaseous effluents during normal operations, including anticipated operational occurrences. ETSBSPLB verifies that water from the mechanical vacuum pumps and condensate from the steam jet air ejectors are classified as radioactive liquids and treated accordingly. 2. ETSBSPLB reviews the equipment quality group classifications to meet the guidelines of Regulatory Guide 1.26 (Ref. 3) . Exceptions are transmitted to MEBEMEB , which has 22 23 primary review responsibility underfor SRP Section 3.2.2. 24 25 3. If there is a potential that explosive mixtures may exist, ETSBSPLB determines whether the applicant has designed the MCES to withstand the effects of such an explosion and has provided instrumentation to detect and annunciate or has provided dual instrumentation on redundant MCES trains to detect, annunciate, and effect control measures to prevent the buildup of potentially explosive mixtures. This