### EPA’s RESPONSE to Summary of Interagency Working Co mments on Draft

Language under EO12866/13563 Interagency Review. S ubject to Further Policy Review.

1 Environmental Protection Agency (EPA): Proposed Rul e

Protection of Visibility: Amendments to Requirement s for State Plans

RIN 2060-AS55

EPA’s Response #1: The EPA proposes to make the following changes in s ection IV.G, Changes to Reasonably Attributable Visibility Impai rment Provisions, on pages 88-91 (changes against existing version in red):

Regarding the time schedule for state response to a n FLM certification of reasonably attributable visibility impairment, we are consider ing a number of possible approaches for the final rule, but with proposed rule text is provided only for the most complicated of these three
alternative approaches. This approach will be explained first.

The first alternative proposed rule text at §51.302 (d) would retain the existing requirement for a state to respond to a reasonably attributable visibility impairment certification with a SIP revision within 3 years regardless of wh en the certification is made in the cycle of periodic comprehensive SIP revisions.

The second alternative proposed rule text at §51.30 2(d) would require the state’s responsive SIP revision to be submitted on the due date of the next progress report (but not as part of the progress report, if the final rule does not require progress reports themselves to be submitted as SIP revisions) or the next periodic co mprehensive SIP revision, whichever is earlier, provided the earlier date is at least 2 ye ars after the RAVI certification.

The third alternative proposed rule text at §51.302(d) provides for diffe rent deadlines for the state response to the certification depending o n when in the cycle of periodic comprehensive SIP revisions the reasonably attributable visibilit y impairment certification is made. Table 2 provides specific examples of how application of th e third alternative approach in the proposed
rule text would determine due dates for the state r esponse to a certification.

• If the certification is made more than 2 years prio r to the due date for any periodic comprehensive regional haze SIP revision required u nder §51.308(f) (but, with respect to the SIP due for the just-prior period, not so early as to be within the 6-month window described next), then a state must respond to the c ertification in that upcoming SIP revision. Failure to respond adequately would preve nt full approval of that SIP revision. If the certification is made more than 2 years befo re the SIP due date, the state would have more than 2 years to respond, except as provid ed in the next bullet. 1

1 Under the third alternative proposed rule text, fF or a certification made between the 2021 and 2028 SIP due dates, the state might have up to 6.5 years to respond, assuming the next bullet does not apply. For a certification made between th e 2028 and 2038 due dates, the state might have up to 9.5 years to respond.

### EPA’s RESPONSE to Summary of Interagency Working Co mments on Draft

Language under EO12866/13563 Interagency Review. S ubject to Further Policy Review.

2 • If the certification is made less than 2 years prio r to the due date for any periodic comprehensive SIP revision (but no more than 6 mont hs subsequent to the submission date of that periodic comprehensive regional haze S IP revision or a SIP revision that amends a previous submission in a way that affects the emission limits applicable to the reasonably attributable visibility impairment-certi fied source 2 ), then the state must submit a revision to its regional haze SIP within 2 years from the date of certification. The EPA believes that in this second timing situati on, when the state’s analytical infrastructure has been recently used to prepare a SIP revision and thus would not be in
need of much

, if any

, refreshment, it is appropriate to require a respon ding SIP revision without waiting longer than 2 years for the next pe riodic comprehensive SIP revision. In this timing situation, the EPA would act on the sta te’s standard regional haze SIP without regard to the not-yet-due obligation for a reasonab ly attributable visibility impairmentresponse SIP revision.

Table 2 - Example FLM Reasonably Attributable Visib ility Impairment Certification Dates and Corresponding Due Dates for State Response Under the Third Alternative Proposed
Rule Text . All assume submission of a SIP revision by July 3 1, 2021, unless otherwise
noted.

Date of FLM certification Proposed due date for sta te response

July 30, 2019 July 31, 2021

August 1, 2019 August 1, 2021

January 30, 2022 January 30, 2024

February 1, 2022 July 31, 2028

April 1, 2022, after late submission of a SIP

on March 1, 2022 April 1, 2024

August 31, 2022, after revised SIP submission on July 31, 2021, affecting the source identified in the reasonably attributable visibility impairment

certification August 31, 2024

2 If a certification is made not too long after a SI P due date, this parenthetical provision contained in the third alternative proposed rule te xt would operate to require the SIP revision needed to respond to the reasonably attributable vi sibility impairment certification to be due sooner than the 6.5 or 9.5 year extreme noted in th e previous footnote.

### EPA’s RESPONSE to Summary of Interagency Working Co mments on Draft

Language under EO12866/13563 Interagency Review. S ubject to Further Policy Review.

3 These timing provisions can be viewed as a compromi se between possibly requiring more than one major planning activity during each (appro ximately) 10-year SIP cycle and obtaining

the benefit of additional emission controls via a r esponse to an FLM certification of reasonably attributable visibility impairment within a reasona ble time period. These provisions in the proposed rule text also reflect the fact that an FL M may, in rare cases, wish to certify a reasonably attributable visibility impairment sourc e after reviewing (and having disagreements with) a SIP that a state has recently submitted to the EPA.

The EPA invites comment on this timing approach sho wn in Table 2 and the proposed rule text, but also on other, simpler approaches that w ould strike a compromise that leans more towards obtaining additional visibility improvement s sooner following a FLM certification of reasonably attributable impairment at a Class I are a. In particular, the EPA invites comment on (1) retaining the existing requirement for a state to respond to a reasonably attributable visibility impairment certification with a SIP revision within 3 years regardless of when the certification is made in the cycle of periodic comprehensive SIP rev isions and (2) requiring the state’s responsive SIP revision to be submitted on the due date of the next progress report (but not as part of the progress report, if the final rule does not require progress reports themselves to be submitted as SIP revisions) or the next periodic co mprehensive SIP revision whichever is earlier provided the earlier date is at least 2 years after the RAVI certification. The final rule may incorporate any one of these three proposals, or ma y combine features of these proposals.

It is important to note that regardless how the fin al rule sets the deadline for the state’s responsive SIP revision, if the reasonable progress goals in the periodic comprehensive regional haze SIP for a state with a Class I area (and thus required to have reasonable progress goals in its SIP for that area) have been approved prior to the approval of its own or a contributing state’s separate reasonably attributable visibility impairm ent-response SIP, the state would not be required to revisit and revise its reasonable progr ess goals to take into account any additional

emission reductions from the certified source until the next due date for a periodic comprehensive SIP revision.

EPA’s Response #2: The EPA also proposes to make the following three r ule text proposals in the alternative for 51.302(d). Note that the third alternative had previously been included as the only rule text proposal and is therefore not shown in red.

§51.302 Reasonably attributable visibility impairme nt.
First alternative for paragraph (d) for the final r ule:
(d) For any existing reasonably attributable visibi lity impairment the Federal Land Manager certifies to the State(s) under paragraph (a) of th is section, the State(s) shall submit a revision to its regional haze implementation plan that includes the elements described in paragraph (b) and (c) no later than 3 years after the date of the cer tification. The State(s) is not required at that ti me

### EPA’s RESPONSE to Summary of Interagency Working Co mments on Draft

Language under EO12866/13563 Interagency Review. S ubject to Further Policy Review.

4 to also revise its reasonable progress goals to ref lect the additional emission reductions required
from the source or sources.
Second alternative for paragraph (d) for the final rule:
(d) For any existing reasonably attributable visibi lity impairment the Federal Land Manager certifies to the State(s) under paragraph (a) of th is section more than 2 years prior to the due date for a regional haze implementation plan revision re quired under §51.308(f) or the due date for a regional haze progress report required under §51.30 8(g), the State(s) shall include the elements described in paragraphs (b) and (c) in a plan revis ion by the due date for that implementation plan revision as part of such revision or by the du e date for the progress report, whichever is due first, provided that the earlier date is at least 2 years after the certification. For plan revisions submitted by the due date for the progress report, the State(s) is not required at that time to also revise its reasonable progress goals to reflect the additional emission reductions required from
the source or sources.

Third alternative for paragraph (d) for the final r ule:
(d)(1) For any existing reasonably attributable vis ibility impairment the Federal Land Manager certifies to the State(s) under paragraph (a) of th is section more than 2 years prior to the due date for a regional haze implementation plan revision re quired under §51.308(f), the State(s) shall include the elements described in paragraphs (b) an d (c) in such revision and such elements shall be considered a required part of such revision.
(2) For any existing reasonably attributable visibi lity impairment the Federal Land Manager certifies to the State(s) under paragraph (a) of th is section less than 2 years prior to the due date for a regional haze implementation plan revision re quired under §51.308(f), but no more than 6 months subsequent to the submission date of that im plementation plan revision or no more than 6 months subsequent to a further plan revision that c hanges the emission limitation for the subject source, the State(s) shall submit a revision to its regional haze implementation plan that includes the elements described in paragraph (b) and (c) no later than 2 years after the date of the certification. The State(s) is not required at that time to also revise its reasonable progress goals to reflect the additional emission reductions requi red from the source or sources.