Date: May 12, 1998

SUBJECT: Halogenated Solvent Cleaning Machine NESHAP

FROM: Elliott J. Gilberg, Director

Chemical, Commercial Services and Municipal Branch

TO: Regional Halogenated Solvent Cleaner MACT Contacts

This letter provides an overview of two recently published Federal Register notices
regarding the halogenated solvent cleaning machine NESHAP and clarifies several
other issues regarding the implementation of the NESHAP.

On May 5, 1998, two Federal Register notices were published to amend the
halogenated solvent cleaning machine NESHAP. These notices: (1) announce an
immediate 3-month stay of the effectiveness of the NESHAP for continuous web
cleaning machines using HAP solvents; and (2) propose a temporary extension of the
applicable compliance date beyond the 3-months stay for up to one year. During the
stay, the Office of Air Quality Planning and Standards (OAQPS) will conduct an
evaluation of methods of control for all continuous web cleaning machines to
determine which emission control measures are equivalent to those provided in the
NESHAP. EPA decided to propose a stay on the NESHAP after becoming aware of
several sources with continuous web cleaning machines that were experiencing
difficulties in determining how to comply with the NESHAP. In each case, the
emission control requirements specified by the NESHAP was difficult or impossible to
implement due to the unique operating and emission characteristics of continuous web
cleaning machines. Unless the Agency receives adverse public comment on the
proposed temporary extension of the 3-month stay, the stay will go into effect at the
end of the immediate 3-month stay. We will keep you apprised of the regulatory status
of continuous web cleaning machines.

In response to several Regions, this letter also provides clarification regarding the
applicability of the halogenated solvent cleaning machine NESHAP to stripping
operations. The use of a halogenated HAP solvent to remove paint, maskant, or a
coating is not subject to this NESHAP. A separate MACT standard for paint
stripping operations is under development.

Finally, this letter provides corrections to the April 1995 Guidance Document for the
Halogenated Solvent Cleaner NESHAP (EPA-435/R-94-081) and question number
1 of the Control Device Specific Questions provided in Appendix A to Subpart T -
Test of Solvent Cleaning Procedures. On page C-14 of the guidance document,
AREA is incorrectly defined as "Amount of halogenated solvent removed from the
machine in solid waste". The correct definition of AREA is "The solvent-air interface
area of the machine in square meters (or square feet" (see page 2-35 definition of
AREA). Regarding question number 1 of the Control Device Specific Questions
provided in Appendix A, as drafted, none of the answers to this question are correct.
Answer D to this question should read: no greater than 30 percent of the solvent
boiling point rather than 30 percent of the solvent boiling point.

Please contact Tracy Back of my staff at (202) 564-7076 or E-mail at
back.tracy@epamail.epa.gov with any questions on the halogenated solvent cleaning
machine NESHAP.