Primary and Secondary Sampling

Question 1

Why is LiOH added to the RCS?

Answer 1

pH Control

Question 2

Discuss Primary Sampling Locations.

Answer 2

RCS Hot Leg 1A [2A], Delay Line 150’ tygon, 90 sec, N16
* High pressure – O2, N2, H2, fission gases
* Low pressure – chloride, boron, other
* CIS override – CLOSE then OPEN in Control Room [local CLOSE, RTGB CLOSE then RESET, local OPEN]
PZR Steam Space – fission products and non-compressible gases
* High pressure
* Low pressure
PZR Surge Line - boron
SDC – boron
SI – boron following LOCA
SIT – boron
* 2 outside [4 inside, header valve outside] CTMT isolation valves close on CIS, local switches [also control switches in Control Room for close/reset only]. No CIS override.
CVCS – DF, particulate activity

Question 3

Discuss the Primary Sample Hood

Answer 3

Located in Sample Room 19.5’ RAB
* Powered by MCC 1A2 [2A2]
* Hot leg sample vessel
* PZR steam space sample vessel

Question 4

Discuss CIAS/CIS impact on sampling.

Answer 4

Isolates RCS sampling lines coming out of containment (all sampling lines coming out of containment including S/G B/D).

Question 5

Discuss Primary Sampling Tech Specs.

Answer 5

LCO 3.4.16
RCS DOSE EQUIVALENT I-131 and DOSE EQUIVALENT XE-133 specific activity shall be within limits.

APPLICABILITY: MODES 1, 2, 3, and 4.

IF DOSE EQUIVALENT I-131 not ≤ 1.0 μCi/gm, verify DOSE EQUIVALENT I-131 ≤ 60 μCi/gm once per 4 hours and restore DOSE EQUIVALENT I-131 to within limit within 48 hours.

IF DOSE EQUIVALENT XE-133 not ≤ 518.9 μCi/gm, restore DOSE EQUIVALENT XE-133 to within limit within 48 hours.

IF above Required Actions and associated Completion Times not met
OR
DOSE EQUIVALENT I-131 > 60 μCi/gm:

Be in MODE 3 in 6 hours
AND
Be in MODE 5 in 36 hours

Question 6

Discuss Secondary Sampling Locations.

Answer 6

Condensate (Hotwells) – cation conductivity, sodium, dissolved oxygen
* > 1 µmhos/cm high alarm
Feedwater – hydrazine (chemical injection sufficient), pH, iron, copper (causes sludge in SGs)
Main Steam – cation conductivity
SGBD – impurities cause scale/corrosion in SGs, keep solids <1ppm
* RTGB isolation switch

Question 7

Discuss Secondary Sampling Tech Specs.

Answer 7

LCO 3.7.16
Secondary Specific Activity

APPLICABILITY: MODES 1, 2, 3, and 4.

IF Specific activity of the secondary coolant is not ≤ 0.10 μCi/gm DOSE EQUIVALENT I-131, Be in MODE 3 in 6 hours and MODE 5 in 36 hours.

Question 8

Discuss Gas Decay Tank Sampling.

Answer 8

T.R. 13.11.1 (Explosive Gas) – The concentration of oxygen in the in-service waste gas decay tank shall be limited to ≤ 2% by volume whenever the hydrogen concentration exceeds 4% by volume.
AND
One explosive gas oxygen monitor shall be FUNCTIONAL with alarm/trip setpoint set to ≤ 2% by volume of oxygen. (During waste gas holdup system operation.)

T.R. 3.11.2 (Gas Storage Tanks) – The quantity of radioactivity contained in each gas storage tank shall be limited to ≤ 165,000 curies of noble gases (DOSE EQUIVALENT Xe-133). (At all times)