CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER C—AIR PROGRAMS (Parts 50–99) > PART 66—ASSESSMENT AND COLLECTION OF NONCOMPLIANCE PENALTIES BY EPA > SUBPART E—Decisions on Exemption Requests and Challenges to Notices of Noncompliance (§66.41 to §66.43)