INFORMATION #3 10-10-1994
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!Ii{ River
INFO
RMAr/ON
MEMORANDUM
TO:
MAYOR AND CITY COUNCIL
FROM:
STEPHEN ROHLF, BUILDING
AND ZONING ADMINISTRATOR
5R
OCTOBER 5, 1994
DATE:
SUBJECT: UPA AND NSP
United Power Association (UPA)
Attached to this memo is a letter dated October 3, 1994, from UPA to Mr.
Todd Biewen from the Minnesota Pollution Control Agency. This letter is in
regards to an exceedance UPA had on carbon monoxide. Carbon monoxide is
an indicator of proper combustion. It is continuously monitored to show
whether or not the refuge derived fuel at UPA is being properly burned to
avoid the production of contaminants.
.
On September 29, 1994, UPA experienced an exceedance on the carbon
monoxide standard in two of their three boilers. This was due to not enough
air flow to these boilers for proper combustion. The reason for the restricted
air flow was that the bag house filters, which remove particulates from the
exhaust gasses, were plugged. Restricted air going out of the system caused
the air entering the system to be restricted also.
The exceedance is regrettable, but what is important with this issue is what
UPA will do to keep this situation from happening again. In the past, other
problems have caused UPA to change operational practices and/or
equipment. UPA has been diligent at keeping problems from reoccurring.
The corrective action for this exceedance can be found on the attached letter
to Mr. Biewen.
NSP
.
On October 4, 1994, at approximately 10:30 PM, a hot load of garbage (on
fire) was delivered to the NSP Refuse Derived Fuel Plant in Elk River. The
fire was contained by the Elk River Fire Department and the sprinkler
system within the building. No fire suppression water left the building,
therefore, the fire was of little consequence.
cc-SRlCouncil
P.O. Box 490 . 13065 Orono Parkway · Elk River, MN 55330 · (612) 441-7420 · Fax: (612) 441-7425
Page 2
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Fire Chief Bruce West, who was at the scene, was able to get a limited tour of
the NSP facility. Staff will try to arrange a complete tour of both the NSP
and UPA facilities for Mr. West, in the near future.
.
.
OCT-04-94 TUE 09:57 AM UNITED POWER ASSOCIATION 612 2412454
P. e..1.
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United Power Assooiatlon
P.O,eol800 . ElkRlver.MN55330-0800 . (612)441-3121
October 3, 1994 File: 8-30-4
---------
Mr. Todd Biewen
Minnesota Pollution Control Agency
520 Lafayette Road
St. Paul, Minnesota 55155
767' Oate fO
Phone.
Fad l-t42- c:..
-dod-O ~
ax'
Dear Mr. Biewan:
On September 29,1994 we experienced exceedances of the carbon monoxide (CO)
emission limitation in Boilers 11 1 and #2 of the Elk River Station. These exceedances
were reported on September 30 to MPCA (your voice mail and Jolm Morrill of your
staft) and to the City of Elk River (Steve Rohlf). Those telephone reports and this
. written report are made pursuant to permit #147-86-0T-I as amended and extended.
The attached report provided the specifics of the exceedances.
Please call us if you need additional infonnation.
Sincerely,
UNITED pQ"~rER A~IATION
4U-VI..~~
J sF. Eggen, ager
nvironmental S rvices
Power Generation
.
JFE:bjn
Attach.
c: City Council, City of Elk River
Steve Rohlf, City of Elk River
John Lichter, City of Elk River
Wayne Hanson, UPA
Carl Sulzer, UP A
Mark Zaban, Hennepin County
Julie Hendricks. MPCA-Brainerd
OCT-04-94 TUE 09:58 AM UNITED POWER ASSOCIATION 612 2~12~54
P.02
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United Power Association - Elk River Station
Notification of Exceed.nce
MPCA Permit No. 147A4600T.1
Average
Time Emission Corrective Unit
Date Period Unit Emission Rate Cause Action Status
29-Sep-Q4 0800-1400 Boiler 1 CO 433 See Below See Below 10.7
29-Sep-Q4 0800-1400 Boiler 2 CO 426 See Below See Below 10.7
U nit Status:
This is the average load in gross megawatts for the duration of the exceedance.
It only includes time the units are on line and burning RDF.
Cause:
During a capability test on the plant the Cleaning system in the fabric filter
failed to adequately clean the bags resulting in a flow restriction in this system.
This restriction limited the amount of combustion air available to the boilers
resulting in an increase in the generation of CO in the combustion process.
.C . -
errectlve Action:
The operators adjusted air and fuel flows and burned natural gas in an allempt to
get the CO below the 400 ppm limit. When the problem could not be corrected with
these operational adjustments these units were taken off RDF fuel and run at minimum
load on gas only. Air infiltration from leaks in the ductwork is believed to be a
contributing factor to the high fabric filter pressure drop during high load operation.
The ductwork will be inspected and repaired as necessary during the next
scheduled plant outage.
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