Major change to monitoring
Major change to monitoring means a modification to federally required monitoring that uses unproven technology or procedures (not generally accepted by the scientific community) or is an entirely new method (sometimes necessary when the required monitoring is unsuitable). A major change to monitoring may be site-specific or may apply to one or more source categories and will almost always set a national precedent. Examples of major changes to monitoring include, but are not limited to:
(1) Use of a new monitoring approach developed to apply to a control technology not contemplated in the applicable regulation;
(2) Use of a predictive emission monitoring system (PEMS) in place of a required continuous emission monitoring system (CEMS);
(3) Use of alternative calibration procedures that do not involve calibration gases or test cells;
(4) Use of an analytical technology that differs from that specified by a performance specification;
(5) Decreased monitoring frequency for a continuous emission monitoring system, continuous opacity monitoring system, predictive emission monitoring system, or continuous parameter monitoring system;
(6) Decreased monitoring frequency for a leak detection and repair program; and
(7) Use of alternative averaging times for reporting purposes.
40 CFR § 63.90
The regulations in this subpart establish procedures consistent with section 112 of the Clean Air Act (Act) (42 U.S.C. 7401-7671q). This subpart establishes procedures for the approval of State rules, programs, or other requirements such as permit terms and conditions to be implemented and enforced in place of certain otherwise applicable section 112 Federal rules, emission standards, or requirements (including section 112 rules promulgated under the authority of the Act prior to the 1990 Amendments to the Act). The authority to implement and enforce section 112 Federal rules as promulgated without changes may be delegated under procedures established in this subpart. In this process, States may seek approval of a State mechanism for receiving delegation of existing and future unchanged Federal section 112 standards. This subpart clarifies which part 63, subpart A General Provisions authorities can be delegated to States. This subpart also establishes procedures for the review and withdrawal of section 112 implementation and enforcement authorities delegated through this subpart. This subpart also establishes procedures for the approval of State rules or programs to establish limitations on the potential to emit pollutants listed in or pursuant to section 112(b) of the Act.