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Q139. Would a boiler (or other combustion unit) that is mounted on a trailer or movable platform, that is used to provide temporary services while facility equipment is serviced, upgraded, or replaced, and where such equipment remains at the facility for > 12 months, still be considered portable and not subject to the reporting rule under §98.30(b)(1)?

A125. No. You are only subject to Subpart AA if you have emissions units listed in 98.270(b) and meet the applicability criteria for pulp and paper manufacturing.

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