POWER June 2015 - 53

PLANT MOTHBALLING
5. They didn't have those in the 1970s! Justin Gallagher,
senior reactor operator, completes a training scenario in the Watts Bar
Unit 2 control room. Courtesy: TVA
confirmed that installed commercially dedicated equipment and/or
components would have been able to perform their intended safety
functions. In total, tests and inspections were conducted on 1,342
commercial-grade items. The TVA continues to test items that have
already been purchased or installed.
Although detractors have emphasized that the plant has been
cobbled together with retrofits and that completion costs are high-
estimated at $4.5 billion-Unit 2 has already accomplished several
significant milestones, including these:
■ Completed hydrostatic pressure testing of the reactor coolant system,
steam generators, and steam supply system.
■ Assembled the nuclear reactor vessel.
■ Conducted open vessel testing verifying that safety-related systems
inject water into the reactor vessel as designed.
■ Finished all environmental impacts from construction.
■ Constructed and outfitted its FLEX storage building in response to
the Fukushima requirements.
In February 2015, the Advisory Committee on Reactor Safeguards,
and verified in accordance with American Society of Mechanical Engineers
(ASME) codes.
Turbine/Generator. A significant amount of work was done, totaling
more than 40,000 individual replacement parts, including one
new high-pressure (HP) turbine; three new low-pressure (LP) turbines;
complete modernization of the generator (Figure 4), including
a RIGI-FLEX rewind of the stator and new retaining rings; exciter
rotor refurbishment; and six new moisture separator reheaters.
Main Control Room. The Unit 2 portion of the control room
(Figure 5) was ergonomically redesigned. The annunciation system
was replaced, and panel indicators, recorders, and controllers were
upgraded.
Cleanliness. Particulate contaminants, such as sand, sawdust,
metal chips, rust, weld splatter, and tape, were removed from accessible
interior surfaces by vacuuming, rinsing, or flushing until particulate
requirements were met.
Warehouse Storage. For equipment kept in warehouses, all
openings were sealed with manufacturer-approved shields to minimize
the introduction of foreign material, and then the equipment
was stored in its appropriate orientation-horizontally or vertically.
Fluids were analyzed for water content and particulates, and internal
heaters were energized to prevent condensation. Motors were
covered with a tarpaulin for dust protection, and vents were kept
open for ventilation.
Overcoming Bumps in the Road
The TVA was fined $70,000 by the NRC in 2013 related to its commercial-grade
dedication (CGD) program, a process used to ensure that
components purchased from a commercial supplier are equivalent to
nuclear-grade items. The intent of the program is to confirm that critical
characteristics of an item, for example material strength or input/output
voltage, are acceptable. The purchaser or an independent third party
verifies acceptability through inspections, tests, or analyses.
The NRC found that the TVA had not properly verified critical
characteristics for an unknown number of safety-related items. It was
determined that cancelation of a Bechtel CGD procedure early in the
project and lack of training on CGD package preparation for the procurement
engineering group contributed to the problem.
Of the 12 packages with potential deficiencies, eight were found
to be acceptable. The remaining four packages required additional
testing and inspection prior to use. The TVA decided to conduct an
independent review of the CGD packages. The NRC noted that tests
June 2015 | POWER
www.powermag.com
an independent review body within the NRC, sent a letter to the NRC
chairman recommending approval of the Watts Bar Unit 2 OL once
remaining work and NRC inspections are complete.
Skaggs concluded, " Even though the construction was started a
long time ago, what we have here is essentially a newly designed
plant, an existing footprint with new equipment or refurbished equipment
that meets original design specifications. " ■
-James M. Hylko (JHylko1@msn.com), MPH, CQA specializes
in safety, quality, and emergency management issues and is a
frequent contributor to POWER.
てず³と がぐざる ずわゆぎ ゆ らわるらゑ ぞゆゎぞる000
IT'S A CHECK-ALL®
̋ Ykfg tcpig qh urtkpi
ugvvkpiu ( ugcv ocvgtkcnu
̋ Cuugodngf vq {qwt gzcev
pggfu
̋ Vjg{ yqtm cu vjg{
ujqwnf kp cp{ qtkgpvcvkqp
̋ Oquv ngcf vkogu ctg nguu
vjcp qpg yggm
̋ VjcvÓu yjcv ocmgu
Ejgem/Cnn®
ejqkeg0
vjg qpn{
UKPEG 3;7:
GET ME A CHECK-ALL®
Manufactured in
West Des Moines, Iowa, USA
′ 737/446/4523 ′ とゆゎるとBらわるらゑゆゎゎ0らぐが ′ だだだ0らわるらゑゆゎゎ0らぐが
CIRCLE 20 ON READER SERVICE CARD
53
!

http://www.powermag.com

POWER June 2015

Table of Contents for the Digital Edition of POWER June 2015