---
kind: "section"
citation: "40 C.F.R. § 97.187"
title: "40"
number: "97.187"
heading: "Change in regulatory status."
url: "https://uscodex.org/cfr/40/97.187"
---

# §97.187. Change in regulatory status.

- (a) **Notification.** If a CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md), then the CAIR designated representative shall notify in writing the permitting authority and the Administrator of such change in the CAIR NOX opt-in unit's regulatory status, within 30 days of such change.
- (b) **Permitting authority's and Administrator's actions.**
  - (1) If a CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md), the permitting authority will revise the CAIR NOX opt-in unit's CAIR opt-in permit to meet the requirements of a CAIR permit under [§ 97.123](/cfr/40/97.123.md), and remove the CAIR opt-in permit provisions, as of the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md).
  - (2)
    - (i) The Administrator will deduct from the compliance account of the source that includes the CAIR NOX opt-in unit that becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md), CAIR NOX allowances equal in amount to and allocated for the same or a prior control period as:
      - (A) Any CAIR NOX allowances allocated to the CAIR NOX opt-in unit under [§ 97.188](/cfr/40/97.188.md) for any control period after the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md); and
      - (B) If the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md) is not December 31, the CAIR NOX allowances allocated to the CAIR NOX opt-in unit under [§ 97.188](/cfr/40/97.188.md) for the control period that includes the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md), multiplied by the ratio of the number of days, in the control period, starting with the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md) divided by the total number of days in the control period and rounded to the nearest whole allowance as appropriate.
    - (ii) The CAIR designated representative shall ensure that the compliance account of the source that includes the CAIR NOX opt-in unit that becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md) contains the CAIR NOX allowances necessary for completion of the deduction under [paragraph (b)(2)(i)](#b-2-i) of this section.
  - (3)
    - (i) For every control period after the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md), the CAIR NOX opt-in unit will be allocated CAIR NOX allowances under [§ 97.142](/cfr/40/97.142.md).
    - (ii) If the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md) is not December 31, the following amount of CAIR NOX allowances will be allocated to the CAIR NOX opt-in unit (as a CAIR NOX unit) under (97.142 for the control period that includes the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md):
      - (A) The amount of CAIR NOX allowances otherwise allocated to the CAIR NOX opt-in unit (as a CAIR NOX unit) under [§ 97.142](/cfr/40/97.142.md) for the control period multiplied by;
      - (B) The ratio of the number of days, in the control period, starting with the date on which the CAIR NOX opt-in unit becomes a CAIR NOX unit under [§ 97.104](/cfr/40/97.104.md), divided by the total number of days in the control period; and
      - (C) **Rounded to the nearest whole allowance as appropriate.**

## Notes

### Amendments

[65 FR 2727, Jan. 18, 2000, as amended at 71 FR 74795, Dec. 13, 2006]

### Authority

Authority: 42 U.S.C. 7401, 7403, 7410, 7426, 7491, 7601, and 7651, et seq.

### Source

Source: 65 FR 2727, Jan. 18, 2000, unless otherwise noted. 71 FR 25396, 25422, and 25443, Apr. 28, 2006

### Amendments

[65 FR 2727, Jan. 18, 2000, as amended at 71 FR 74795, Dec. 13, 2006]