October 31, 1996

Honorable Herbert Kohl
United States Senator
14 West Mifflin Street
Suite 312
Madison, Wisconsin 53703

Dear Senator Kohl:

Thank you for your October 14, 1996, letter requesting information on the air pollution control
permit issued to Minergy Corporation-Fox Valley Glass Aggregate Plant in Neenah, Wisconsin
(permit number 95-RV-066). On April 30, 1996, the Wisconsin Department of Natural
Resources (WDNR) issued a Prevention of Significant Deterioration (PSD) permit to the
facility, authorizing it to construct and initially operate a cyclone furnace capable of firing natural
gas and paper mill sludge, and a materials handling system for a glass aggregate
manufacturing facility.

The State of Wisconsin has been delegated the authority to implement the PSD permit
program to issue and enforce permits to sources within the State. WDNR follows the new
source review guidance which has been provided to the State, including the guidance with
respect to making best available control technology (BACT) determinations, known as the
"top-down method", when issuing a PSD permit to a facility to construct or modify. In brief, the
top-down process provides that all available control technologies are ranked in descending
order of control effectiveness. The PSD applicant first examines the most stringent alternative.
That alterative is established as BACT unless the applicant demonstrates, and the permitting
authority in its informed judgement agrees, that technical considerations, or energy,
environmental, or economic impacts justify a conclusion that the most stringent technology is
not "achievable" in that case. If the most stringent technology is eliminated through this
process, then the next most stringent alternative is considered, and so on. The United States

Environmental Protection Agency (USEPA) does not expect an applicant to necessarily
accept an emission limit or control technology solely because it was required previously of a
similar source type. The permitting authority performs a BACT analysis on a case-by-case
basis in determining the specific emission limitations and control technologies for each
individual source.

The WDNR analyzed and reviewed the information submitted in Minergy's application for its
sulfur dioxide (SO2) BACT analysis, and determined that the control technology specified in
your letter, scrubbers, would be economically and technically infeasible. WDNR determined
instead that BACT for SO2 would be that (1) the permittee may fire only paper mill sludge and
natural gas, and (2) SO2 emissions at the stack may not exceed 168.0 pounds per hour over
any 24 hour consecutive hours of operation and 50 tons per month as determined on a 12
month rolling average. The permittee must demonstrate compliance with the emissions limits
by the use of a continuous emission monitor. The hourly emission rate is set to protect the SO2
ambient air quality standards and PSD increments. In addition, the permittee must limit the
maximum sulfur content in the paper sludge on an "as fired" basis to 0.12 percent by weight,
and the hourly emission rate may not exceed 7.69 pounds per hour. In order to assure that the
permit conditions are being achieved, the facility is required by the permit to conduct a

compliance demonstration within 90 days after the start of initial operation.

If I can provide you with any other assistance in this matter, please do not hesitate to contact

Sincerely yours,


Valdas V. Adamkus
Regional Administrator

Donald F. Theiler, Director
Bureau of Air Management
Wisconsin Department of Natural Resources