September 4, 2008

I recently became aware that the NRC is soliciting Public Comments on
Documents Under Consideration To Establish the Technical Basis for New
Performance-Based Emergency Core Cooling System Requirements and that
Comments on these documents should be submitted by September 5, 2008.
The NRC announced the availability of Research Information Letter (RIL)
0801, ''Technical Basis for Revision of Embrittlement Criteria in 10CFR
50.46'' and NUREG/CR--6967, ''Cladding Embrittlement During Postulated
Loss-of-Coolant Accidents,'' and that it is seeking public comment on
these documents.

It is interesting that the NRC solicits Public Comments related to crud
deposition as follows:

*II. Performance-Based Testing Requirements*

*3. Crud deposits on the fuel cladding surface may affect fuel stored
energy, fuel rod heat transfer, and cladding corrosion.*

*a. What role does plant chemistry and crud deposits play on these
items?*

*b. How should normal and abnormal levels of crud deposits be addressed
from a regulatory perspective?*

### This is interesting because the word *crud* is not in RIL 0801 and it appears only once in NUREG/CR--6967. Each document has no discussion that focuses on crud.

### Regarding item a, crud deposits play a very significant role in increasing fuel stored energy, in degrading fuel heat transfer and in accelerating cladding corrosion. NRC should apply its expertise including its tools such as TRACE and RELAP in determining the impact of crud in these areas. 

### Regarding item b, crud deposits must be recognized as a very significant item from a regulatory perspective. For example, several nuclear power reactors have deployed ultrasonic fuel cleaning without any oversight by experts within the NRC headquarters. Ultrasonic fuel cleaning has never received an evaluation by the ACRS. Ultrasonic fuel cleaning is basically unregulated. And, returning to TRACE and RELAP, those codes must be applied in determining the impact of crud on LOCAs or RIAs.

### Regulations should require informing the public of the hazards to which they have been potentially exposed when crud is found. For example, the fact that a LOCA or RIA has not occurred does not mean that the public should not be told that the consequences of an accident could have been significantly different than licensing documents reveal.

### Fouling of Nuclear Fuel Elements is Ubiquitous 

### Fouling of nuclear fuel elements is ubiquitous among the worldwide fleet of light water reactors. The NRC has generally been oblivious to the impact of fouling on fuel element performance. The NRC has never performed analyses of the impact of fouling on the ongoing performance of LWR fuel; TRACE, RELAP, and other codes have never been applied. 

### Following are a very few of the records that reveal the development, the marketing and the field applications of Ultrasonic Fuel Cleaning. It is significant to note that the widespread applications of Ultrasonic Fuel Cleaning have only had in-house approvals via 10 CFR 50.59 schemes; there have been no evaluations by NRC technology groups and there has been no detailed evaluation of the technology by the ACRS. 

### [Ultrasonic Fuel Cleaning: AREVA, EPRI, Westinghouse, Dominion and more](http://nuclearpowerblog.blogspot.com/2008/09/ultrasonic-fuel-cleaning-by-areva.html) 

Go to GOOGLE and enter Ultrasonic Fuel Cleaning. Hunt a bit and you will
find a lot: Areva, EPRI, 50.59 game,

Following is the text of Areva\'s advertisement, minus the photographs.\
\
Ultrasonic Fuel Cleaning\
\
Effective fuel cleaning technology to help assure performance and
improve safety. AREVA NP offers patented Electric Power Research
Institute (EPRI) Ultrasonic Fuel Cleaning (UFC) to prevent uneven crud
deposits that can negatively affect fuel performance. With proven
performance in applications at several domestic U.S. utilities, UFC can
also reduce dose rates on primary components contaminated by the
migration of activation products from core surfaces. Plus, we are an
official EPRI licensee authorized to supply UFC equipment and services
to nuclear stations worldwide. We can provide UFC for your next outage.\
\
UFC was developed by EPRI to eliminate in-core flux depression by
effectively removing deposits from fuel assemblies during refueling
outages. Ultrasonic waves cause small particles of crud to release from
the fuel assembly. Fuel pool water cools the fuel and transports
particles to the filter banks where they are collected for final
disposal. The system employs disposable filters to remove radioactive
corrosion and activation products. Customers can store the filters in
their fuel pool or process them for immediate shipping.\
\
Cleaning Chamber Ensures Even Distribution A special cleaning chamber,
similar to a fuel rack, holds ultrasonic transducers positioned on each
face of the fuel assembly in an overlapping pattern. This configuration
ensures even distribution of the ultrasonic energy into the fuel
assembly. Reliable Console Controls the Process An operating console,
located on the refuel floor near the edge of the spent fuel pool or
reactor vessel, controls the process. The operator can easily observe
the cleaning parameters and performance of the filtration unit.
Underwater Filters Capture Removed Deposits. The underwater filters
contain removed deposits while maintaining radiation to acceptable
levels. A variety of filtration system designs are available to provide
custom optimization.\
\
BENEFITS\
BWR or PWR application\
Effectively removes crud\
Improves fuel flux distribution\
Improves fuel utilization\
Reduces radiation source term\
Reduces primary system dose rate\
\
And here is the notice of EPRI\'s R&D award, also on GOOGLE:\
[October 05, 2005 09:00 AM Eastern Daylight
Time](http://www.businesswire.com/news/google/20051005005383/en)\
EPRI\'s Patented Nuclear Fuel Cleaning Technology Receives R&D 100
Award; Award Reception Slated for Oct. 20\
PALO ALTO, Calif.\--([BUSINESS
WIRE](http://www.businesswire.com/))\--Oct. 5, 2005\--The Electric Power
Research Institute (EPRI), three member companies, AmerenUE, Exelon
Corp., and South Texas Project Nuclear Operating Co., and Dominion
Engineering, Inc. (DEI) have earned a prestigious 2005 R&D 100 Award for
ultrasonic cleaning of nuclear fuel, a promising new technology that
safely removes deposits from irradiated fuel assemblies in nuclear power
plants.\
The annual awards are given by R&D Magazine for the most outstanding
technology developments with commercial potential. The award reception
will take place Thursday, Oct. 20 in Chicago; EPRI Senior Vice President
and Chief Technology Officer Ted Marston is scheduled to attend.\
\"The future of the energy industry relies on pursuing innovative
technologies that advance efficient, reliable and environmentally
sensitive power generation and transmission,\" said EPRI CEO Steven R.
Specker. \"I applaud our team and member companies for their
contribution towards this end.\"\
The technology awarded delivers a patented process for removing
corrosion products deposited on irradiated nuclear fuel pins using a
unique form of ultrasonic technology. The technology was first applied
at their nuclear power plants by the three EPRI member companies noted
above, using equipment supplied by DEI.\
\"We were pleased to hear that our technology received an R&D Award,\"
said Christopher J. Wood, a technical manager in EPRI\'s Nuclear Sector.
\"This breakthrough technology allows the full potential of current
nuclear fuel designs to be achieved while maintaining excellent fuel
reliability. Availability of a safe, reliable cleaning technology will
also now allow utilities to further optimize fuel performance, core
design, and reduce radiation fields and electricity generating costs.\"\
This unique technology, developed in EPRI\'s Fuel Reliability Program,
solves a significant emerging problem by removing deposits from nuclear
fuel assemblies in nuclear power plants. Enhancing the performance of
nuclear fuel is crucial to continue the improvement in electricity
production from nuclear units. Over the past decade, nuclear power
production has increased by over 20 percent, but this has placed
additional demands on the fuel, as fuel temperatures have increased.\
Some of the potential problems with fuel reliability result from the
buildup of deposits on the surfaces of the fuel elements, which produces
an insulating layer that could result in corrosion of the fuel cladding
material at increased fuel pin temperatures. Until EPRI\'s developed
technology, there was no effective way of removing these deposits during
the working life of the fuel. Including early development
demonstrations, this ultrasonic fuel cleaning technology has been used
successfully eight times at nuclear power plants in the USA through
2004, and has been licensed worldwide. Seven additional commercial
applications have taken place in 2005, including one in Spain. The
technology used cleans all the fuel elements in every fuel assembly
without any adverse effects. The cleaning process does not extend the
schedule of routine refueling outages and is very cost-effective in
pressurized water reactors. It is expected to result in a major
reduction in radiation fields in boiling water reactors.\
About the Electric Power Research Institute\
The Electric Power Research Institute (EPRI), with major locations in
Palo Alto, California, and Charlotte, North Carolina, was established in
1973 as an independent, nonprofit center for public interest energy and
environmental research. EPRI brings together member organizations, the
Institute\'s scientists and engineers, and other leading experts to work
collaboratively on solutions to the challenges of electric power. These
solutions span nearly every area of power generation, delivery, and use,
including health, safety, and environment. EPRI\'s members represent
over 90% of the electricity generated in the United States.
International participation represents nearly 15% of EPRI\'s total R&D
program.\
\
And here is how NRC accepted Ultrasonic Fuel Cleaning under 50.59!

![](media/image1.jpeg){width="6.075in" height="4.694444444444445in"}And
here we have EPRI, way back in 1999, highlighting its Ultrasonic Fuel
Cleaning Process at Callaway as a 1999 payoff:

![](media/image2.jpeg){width="5.925in"
height="4.5777777777777775in"}And, during September 2003, Westinghouse
advertised its ultrasonic fuel cleaning service. \"As a result, the
plant safety review committee granted the application 10 CFR 50.59
approval.\"

**Ultrasonic cleaning means fast, safe removal of fuel-assembly crud
buildup**

Crud --- corrosion products that accumulate on fuel surfaces --- can
break loose and spread to other parts of the system, causing radioactive
buildup. Over time, crud that builds up on fuel surfaces becomes
activated by neutrons to form radioactive nuclides, making crud cleanup
a high priority.\
Ultrasonic fuel cleaning can break up crud deposits during normal
refueling, trapping particulates in filters for storage in the fuel
pool. Designed by Dominion Engineering, Inc. (DEI), and patented by
EPRI, the technique blasts crud with ultrasonic transducers.\
Ultrasonic cleaning reduces the risk of fuel damage and takes a fraction
of the time required by other methods. Controlling crud and other
particulate inventory reduces out-of-core radiation fields and lowers
radiation dosage levels.\
Eliminating crud also mitigates local in-core flux supression and
decreases the likelihood of axial offset anomaly (AOA) caused by lithium
and boron concentrations. Ultrasonic cleaning also helps prevent
crud-induced power shifts that can reduce output by as much as 20
percent.\
Ultrasonic fuel cleaning was first used and verified at the Callaway
plant in Missouri in 2001. After a year, no evidence of core-wide AOA
was found, and early ex-core dosage was reduced significantly with no
impact on critical path time. Measurements of assemblies before and
after cleaning, and of particulate discharge at the filters, showed that
ultrasound cuts crud deposits by about 80 percent. **As a result, the
plant safety review committee granted the application 10 CFR 50.59
approval.\
**Ultrasonic cleaning is fast, too. During routine refueling, an
assembly scheduled for reuse can be cleaned in as little as seven to ten
minutes. Westinghouse is the first vendor to use this technique
commercially. Our partnership with DEI gives utilities access to
ultrasonic cleaning with minimal incremental costs.

Dominion (DEI), the inventors of Ultrasonic Fuel Cleaning, may have
discussed Ultrasonic Fuel Cleaning Process/Success at a very recent
meeting of PWR operators.\
Sunday, July 20, 2008\
**PWR ALARA Association Board Meeting** - Board Room\
Wednesday, July 23, 2008\
General PWR Session -- Day 2\
10:00 Ultrasonic Fuel Cleaning Process/Success -- Dr. Robert Verrin
(Dominion Engineering) Tentative

Submitted by:

Robert H. Leyse

P. O. Box 2850

Sun Valley, ID 83353