Source: Alan Newman, Washington State Department of Ecology

 

Increment over consumption is intended to be remedied through a SIP change per 40 CFR 51.166(a)(3).

EPA in 1978 (Preamble to 1978 version of PSD regulation) would consider offsets to keep increment from being over-consumed in accordance with prior practices.  Preamble includes discussion about increment expansion when baseline and increment consuming sources cease operation or reduce emissions.

Minor, area, and mobile sources consume increment and can expand increment through their ceasing operation or reducing emissions.

 

Increment consumption and its relationship to minor, area and mobile sources

 

I.                   Legal history

A.     First proposed in July 1973[1] and finally enacted in December, 1975

1.      Enacted for SO2 and TSP

2.      Set at a fraction of the NAAQS

3.      Focus to implement the Act’s PSD provisions.

a.      Included Class 1, 2 and 3 areas, set all country at Class 2, mechanism for FLM’s and states to designate Class 1 areas.

b.      Most problems were with the Class 3 area designations and procedures

c.      Envisioned increment consumption compliance through dispersion modeling

d.      Envisioned that EPA and states would have a formalized procedure to track increment consumption

e.      Increment consumption would be calculated by sources required to get PSD permits

 

B.     Readjusted language in 1977 amendment to fCAAA

1.      Modified program in 1978 PSD rules

a.      Established a formalized class 3 area designation with increments

b.      Established the mandatory federal Class 1 areas and FLM responsibility to protect AQRV’s in those areas

c.      Made procedural changes to increment process

d.      Detailed discussion of Increments, increment tracking and determination in the rule preamble (Proposed rules, Nov. 3, 1977 and final rules June 19, 1978)

e.      Established list of actions exempt from increment consumption

2.      Required increment protection in SIPs

a.      Based on criteria in fCAAA section 163(b)

b.      Preamble (at FR Vol. 43, No. 118, Page 26380 - 26381, June 19, 1978) discusses increment consumption as occurring due to all sources and that the periodic assessment during major source reviews (new and modified sources) was adequate to protect increment.

c.      Reiterated list of activities exempt for increment consumption (40 CFR 51.166(f))

i.                     Concentrations attributable to the increase in emissions from stationary sources which have converted from oil or natural gas due to an order under section 2(a) and (b) of the Energy Supply and Environmental Coordination Act of 1974 for no more than 5 years after the order is issued.

ii.                    Concentrations attributable to the increase in emissions from stationary sources which have converted from natural gas by reason of natural gas curtailment plan in effect pursuant to the Federal Power Act over the emissions from such sources before the effective date of such plan

iii.                   Concentrations of particulate matter attributable to emissions form construction or other temporary emission-related activities of new or modified sources

iv.                 The increase in concentrations attributable to new sources outside of the United States above emissions included in the baseline concentrations

v.                  Concentrations attributable to the temporary increase in emissions of SO2 and NOx from stationary sources which are temporary in nature (less than 2 years duration) or a longer time approved by EPA and the temporary increase is not renewable 

 

C        Regulations issued Aug. 7, 1980 in response to Alabama Power suit dealt with many issues including increment consumption. (FR Vol. 45, No. 154, Aug. 7, 1980, Pages 52717 – 52722)

1.      Preamble gave guidance that increment consumption should be based on actual emissions for existing sources and allowable for new sources.

2.      Reiterated temporary emissions as being exempt from increment consumption

3.      Preamble discussion on potential increment violations, but no new discussion on solutions.

 

D       NOx addition in 1988

1.      Added NO2 to list of increments set 1988 for the NOx major source baseline date.

E        There is no equivalent concept in Washington law.  Ecology has incorporated the concept of increments into its regulations through adoption of 40 CFR 52.21.  This adoption has not included the concept of increment tracking beyond the discussions in the various rule preambles.

F        June 3, 1993 (58 FR 31636) EPA issued regulations that deleted listing of activities excluded from consuming increment, but only in EPA’s 52.21 PSD program.  The list still is included in the guidelines for state programs.

 

II.                Program requirements

A.     Increment values

               ────────────────────────────────────────────────

 

 

                          MAXIMUM ALLOWABLE INCREASE

                                                             Maximum allow‑

                                                             able increase

                         Pollutant                            (micrograms

                                                               per cubic

                                                                 meter)

                                  Class I

Particulate matter:

 PM‑10, annual arithmetic mean.............................               4

 PM‑10, 24‑hr maximum......................................               8

Sulfur dioxide:

 Annual arithmetic mean....................................               2

 24‑hr maximum.............................................               5

 3‑hr maximum..............................................              25

Nitrogen dioxide:

 Annual arithmetic mean....................................             2.5

                                 Class II

Particulate matter:

 PM‑10, annual arithmetic mean.............................              17

 PM‑10, 24‑hr maximum......................................              30

Sulfur dioxide:

 Annual arithmetic mean....................................              20

 24‑hr maximum.............................................              91

 3‑hr maximum..............................................             512

Nitrogen dioxide:

 Annual arithmetic mean....................................              25

                                 Class III

Particulate matter

 PM‑10, annual arithmetic mean.............................              34

 PM‑10, 24‑hr maximum......................................              60

 Sulfur dioxide:

 Annual arithmetic mean....................................              40

 24‑hr maximum.............................................             182

 3‑hr maximum..............................................             700

Nitrogen dioxide:

 Annual arithmetic mean....................................              50

 

 

               ────────────────────────────────────────────────

 

[52.21(c) table revised at 58 FR 31636, June 3, 1993]

 

          B. What sources consume Increment

1. All sources after baseline dates have been set (See table of baseline dates in Washington)

2. Major sources, new and modifications to existing major sources after the major source baseline date.

3. Minor sources that have come into existence since the minor source baseline has been set

4. Area sources that have come into existence since the minor source baseline has been set

5. Mobile source emission increases that have come into existence since the minor source baseline has been set

 

          C. When is increment consumption calculated?

 

1. Expectation in fed regulations

 

The regulations do not proscribe any particular methodology to calculate increment consumption or tracking.  The general program requirements in 40 CFR 51.166 contain language that requires the states to protect increment from being over-consumed.  The Regulation does require the states to develop regulatory requirements (submit a SIP amendment) when a location with over-consumed increment has been found.  The SIP amendment is to address specific actions that the state will take to eliminate the increment over-consumption.

The various preambles to the regulations go over the expectations for determining increment consumption.  While the mid 70’s regulations envision the possibility to use ambient monitoring to determine both the baseline concentrations, EPA’s 1978 and 1979 recommendations were to use dispersion modeling and actual emissions on the baseline date to analyze increment consumption.   The 1978 and 1979 PSD program preambles[2] (to the EPA PSD program and the EPA’s requirements for SIP PSD programs) anticipate that the states would routinely evaluate increment consumption as part of their SIP new source review programs, but did not stipulate the time between periodic reviews as a requirement of the regulation.

 

For their own PSD program, EPA considered that the calculation of increment consumption would be adequately evaluated (calculated) by the major source permits in an area.  In fact, during the late 1970’s and early 1980’s EPA seems to have been more concerned about a single source consuming all available increment rather than the long-term need to track it’s consumption. 

 

There is additional discussion on protection of increment, though minimal discussion of remedies beyond requiring emission reductions at existing facilities and the generation of emission offsets by major source project applicants.

 

2. Expectation in 1990 Draft NSR manual

 

The 1990 NSR manual also anticipates, just like the prior regulatory preambles, that increment consumption would only be calculated by major source project applicants.

 

3. Current practice in Washington

a. During PSD air quality impact modeling (This is a required element of the permit application process). 

          b. Other occasions when desired /requested by the local authority

          c. Indirectly when doing NAAQS compliance modeling for minor NSR

 

          D. Increment generation

PSD increment can be generated by major sources and by other sources that consume increment.  The EPA guidance contained in the regulation preambles note that federally enforceable, actual emissions reductions from major sources that are part of the baseline emissions for the area generate increment (45 FR No. 154, August 7, 1980, page 52721, col. 1 and (FR Vol. 43, #118, Monday June 19, 1978, Pages 26400 – 26402).  The emission reductions from the major sources can come from installation of emissions controls, or the shutdown of sources or emission units.

 

Of necessity, EPA focuses on major sources, but in the 1990 Draft NSR Workshop Manual, in Chapter C.IV.C.2  and D.4. notes increment can be generated by means of:

                   1. Shutdown of plants

                             a. In the baseline emissions

                             b. Increment consuming plants permitted since baseline dates,

                   2. Reduction of actual emissions by sources in baseline

                   3. Reduction in allowable emissions by increment consuming sources

 

          E. Increment Protection required

                   1. Required by regulations (cite)

                   2. Once per year exceedence allowance

 

III.           Increment overconsumption, issues and remedies

 

A.     How is increment over consumption found?

1.      From dispersion modeling done either by major sources for their PSD permitting exercises

2.      By a local agency or the state when performing dispersion modeling for other purposes (such as determination of NAAQS compliance by a minor source)

3.      From ambient monitoring if ambient monitoring is adequate to determine if a change has occurred.  EPA does not consider ambient monitoring to be the best way to track increment consumption due to year to year variability in ambient concentrations at any given monitor (see FR Vol. 39 No. 167, August 27, 1974, pages 31004 – 31005, preamble discussion on usage of ambient measurements and dispersion modeling for increment consumption deterioration; see also, FR Vol. 43, No. 118, June 19, 1978, pages 26400 - 26402).

 

B.     Once over consumption of increment is found, EPA’s PSD regulations require the state (or EPA where it is the PSD permitting agency) to remedy the over consumption of increment.  There are a few opportunities to reduce increment consumption available depending on the cause of the over consumption.   The fixes identified in various EPA documents and would be allowed under Ecology regulations are:

1.      Further emission reductions by a proposed project’s applicant to reduce its consumption of available increment.  These would be emission reductions that may go well beyond BACT requirements or control currently uncontrolled or under-controlled emission units within the applicant’s own facility.

2.      The applicant can acquire emission reductions (offsets) from other facilities that emit the same pollutant.  These emission reductions would have to be real emission reductions (not reductions in current allowable emissions) and the reductions would have to be backed up by permit requirements.  The permit requirements might have to be included in orders issued to both the source providing the offsets and the one needing the offsets to assure that the offsetting emission reductions occur and are maintained.

3.      If the over consumption of increment is found by dispersion modeling done for non-permitting purposes, the state or local agency could initiate RACT actions requiring all contributing sources to evaluate the ability to install controls and to install those controls.

4.      If the state or local agency does not do any of the above actions, EPA could issue a SIP Call to force action by the state or local agency to do one or more of the above actions.


52.21(c) Ambient air increments. In areas designated as Class I, II or III, increases in pollutant concentration over the baseline concentration shall be limited to the following:

 

               ────────────────────────────────────────────────

 

 

                          MAXIMUM ALLOWABLE INCREASE

                                                             Maximum allow‑

                                                             able increase

                         Pollutant                            (micrograms

                                                               per cubic

                                                                 meter)

                                  Class I

Particulate matter:

 PM‑10, annual arithmetic mean.............................               4

 PM‑10, 24‑hr maximum......................................               8

Sulfur dioxide:

 Annual arithmetic mean....................................               2

 24‑hr maximum.............................................               5

 3‑hr maximum..............................................              25

Nitrogen dioxide:

 Annual arithmetic mean....................................             2.5

                                 Class II

Particulate matter:

 PM‑10, annual arithmetic mean.............................              17

 PM‑10, 24‑hr maximum......................................              30

Sulfur dioxide:

 Annual arithmetic mean....................................              20

 24‑hr maximum.............................................              91

 3‑hr maximum..............................................             512

Nitrogen dioxide:

 Annual arithmetic mean....................................              25

                                 Class III

Particulate matter

 PM‑10, annual arithmetic mean.............................              34

 PM‑10, 24‑hr maximum......................................              60

 Sulfur dioxide:

 Annual arithmetic mean....................................              40

 24‑hr maximum.............................................             182

 3‑hr maximum..............................................             700

Nitrogen dioxide:

 Annual arithmetic mean....................................              50

 

 

               ────────────────────────────────────────────────

 

[52.21(c) table revised at 58 FR 31636, June 3, 1993]

 

   For any period other than an annual period, the applicable maximum allowable increase may be exceeded during one such period per year at any one location.

 

52.21(d) Ambient air ceilings. No concentration of a pollutant shall exceed:

 

          (1) The concentration permitted under the national secondary ambient air quality standard, or

 

          (2) The concentration permitted under the national primary ambient air quality standard, whichever concentration is lowest for the pollutant for a period of exposure.

 

52.21(e) Restrictions on area classifications.

 

          (1) All of the following areas which were in existence on August 7, 1977, shall be Class I areas and may not be redesignated:

 

                   (i) International parks,

 

                   (ii) National wilderness areas which exceed 5,000 acres in size,

 

                   (iii) National memorial parks which exceed 5,000 acres in size, and

 

                   (iv) National parks which exceed 6,000 acres in size.

 

          (2) Areas which were redesignated as Class I under regulations promulgated before August 7, 1977, shall remain Class I, but may be redesignated as provided in this section.

 

          (3) Any other area, unless otherwise specified in the legislation creating such an area, is initially designated Class II, but may be redesignated as provided in this section.

 

          (4) The following areas may be redesignated only as Class I or II:

 

                   (i) An area which as of August 7, 1977, exceeded 10,000 acres in size and was a national monument, a national primitive area, a national preserve, a national recreational area, a national wild and scenic river, a national wildlife refuge, a national lakeshore or seashore; and

 

                   (ii) A national park or national wilderness area established after August 7, 1977, which exceeds 10,000 acres in size.

 

52.21(f) [Removed]

[52.21(f) removed and reserved at 58 FR 31636, June 3, 1993]

 

 

52.21(g) Redesignation.

 

52.21(g)(1) All areas (except as otherwise provided under paragraph (e) of this section) are designated Class II as of December 5, 1974. Redesignation (except as otherwise precluded by paragraph (e) of this section) may be proposed by the respective States or Indian Governing Bodies, as provided below, subject to approval by the Administrator as a revision to the applicable State implementation plan.

 

52.21(g)(2) The State may submit to the Administrator a proposal to redesignate areas of the State Class I or Class II provided that:

 

          (i) At least one public hearing has been held in accordance with procedures established in 51.102 of this chapter;

 

          (ii) Other States, Indian Governing Bodies, and Federal Land Managers whose lands may be affected by the proposed redesignation were notified at least 30 days prior to the public hearing;

 

          (iii) A discussion of the reasons for the proposed redesignation, including a satisfactory description and analysis of the health, environmental, economic, social and energy effects of the proposed redesignation, was prepared and made available for public inspection at least 30 days prior to the hearing and the notice announcing the hearing contained appropriate notification of the availability of such discussion;

 

          (iv) Prior to the issuance of notice respecting the redesignation of an area that includes any Federal lands, the State has provided written notice to the appropriate Federal Land Manager and afforded adequate opportunity (not in excess of 60 days) to confer with the State respecting the redesignation and to submit written comments and recommendations. In redesignating any area with respect to which any Federal Land Manager had submitted written comments and recommendations, the State shall have published a list of any inconsistency between such redesignation and such comments and recommendations (together with the reasons for making such redesignation against the recommendation of the Federal Land Manager); and

 

          (v) The State has proposed the redesignation after consultation with the elected leadership of local and other substate general purpose governments in the area covered by the proposed redesignation.

 

52.21(g)(3) Any area other than an area to which paragraph (e) of this section refers may be redesignated as Class III if‑‑

 

          (i) The redesignation would meet the requirements of paragraph (g)(2) of this section;

 

          (ii) The redesignation, except any established by an Indian Governing Body, has been specifically approved by the Governor of the State, after consultation with the appropriate committees of the legislature, if it is in session, or with the leadership of the legislature, if it is not in session (unless State law provides that the redesignation must be specifically approved by State legislation) and if general purpose units of local government representing a majority of the residents of the area to be redesignated enact legislation or pass resolutions concurring in the redesignation:

 

          (iii) The redesignation would not cause, or contribute to, a concentration of any air pollutant which would exceed any maximum allowable increase permitted under the classification of any other area or any national ambient air quality standard; and

 

          (iv) Any permit application for any major stationary source or major modification, subject to review under paragraph (l) of this section, which could receive a permit under this section only if the area in question were redesignated as Class III, and any material submitted as part of that application, were available insofar as was practicable for public inspection prior to any public hearing on redesignation of the area as Class III.

 

52.21(g)(4) Lands within the exterior boundaries of Indian Reservations may be redesignated only by the appropriate Indian Governing Body. The appropriate Indian Governing Body may submit to the Administrator a proposal to redesignate areas Class I, Class II, or Class III: Provided, That:

 

          (i) The Indian Governing Body has followed procedures equivalent to those required of a State under paragraphs (g)(2), (g)(3)(iii), and (g)(3)(iv) of this section; and

 

          (ii) Such redesignation is proposed after consultation with the State(s) in which the Indian Reservation is located and which border the Indian Reservation.

 

52.21(g)(5) The Administrator shall disapprove, within 90 days of submission, a proposed redesignation of any area only if he finds, after notice and opportunity for public hearing, that such redesignation does not meet the procedural requirements of this paragraph or is inconsistent with paragraph (e) of this section. If any such disapproval occurs, the classification of the area shall be that which was in effect prior to the redesignation which was disapproved.

 

52.21(g)(6) If the Administrator disapproves any proposed redesignation, the State or Indian Governing Body, as appropriate, may resubmit the proposal after correcting the deficiencies noted by the Administrator.


§ 51.166 Prevention of significant deterioration of air quality.

(a)(1) Plan requirements. In accordance with the policy of section 101(b)(1) of the act and the purposes of section 160 of the Act, each applicable State implementation plan shall contain emission limitations and such other measures as may be necessary to prevent significant deterioration of air quality.

(2) Plan revisions. If a State Implementation Plan revision would result in increased air quality deterioration over any baseline concentration, the plan revision shall include a demonstration that it will not cause or contribute to a violation of the applicable increment(s). If a plan revision proposing less restrictive requirements was submitted after August 7, 1977 but on or before any applicable baseline date and was pending action by the Administrator on that date, no such demonstration is necessary with respect to the area for which a baseline date would be established before final action is taken on the plan revision. Instead, the assessment described in paragraph (a)(4) of this section shall review the expected impact to the applicable increment(s).

(3) Required plan revision. If the State or the Administrator determines that a plan is substantially inadequate to prevent significant deterioration or that an applicable increment is being violated, the plan shall be revised to correct the inadequacy or the violation. The plan shall be revised within 60 days of such a finding by a State or within 60 days following notification by the Administrator, or by such later date as prescribed by the Administrator after consultation with the State.

(4) Plan assessment. The State shall review the adequacy of a plan on a periodic basis and within 60 days of such time as information becomes available that an applicable increment is being violated.

(5) Public participation. Any State action taken under this paragraph shall be subject to the opportunity for public hearing in accordance with procedures equivalent to those established in § 51.102.

(6) Amendments. (i) Any State required to revise its implementation plan by reason of an amendment to this section, including any amendment adopted simultaneously with this paragraph, shall adopt and submit such plan revision to the Administrator for approval within 9 months after the effective date of the new amendments.

(ii) Any revision to an implementation plan that would amend the provisions for the prevention of significant air quality deterioration in the plan shall specify when and as to what sources and modifications the revision is to take effect.

(iii) Any revision to an implementation plan that an amendment to this section required shall take effect no later than the date of its approval and may operate prospectively.



PSD program Baseline Dates

 

Major Source Baseline Dates were set by rule by EPA in the past.

 

Pollutant

Date of Baseline

PM/PM10.

August 6, 1977

SO2

August 6, 1977

NOx

February 8, 1988

 

Minor Source Baseline dates are set for each Air Quality control region of the State, and for each pollutant.

 

TSP

AQCR

AQCR Name

PSD #

Applicant

City

Date

062

E. WA-Idaho

X79 – 03-M

Murphy Brothers, Inc.

Spokane

3-2-79

193

Portland-SW WA

92-03

Weyerhaeuser

Longview

4-28-92

227

N. WA

X79-07

Boise Cascade Lumber

Kettle Falls

3-20-79

228

Oly-NW WA

X80-02

Puget sound Power & Light

Pt. Whitehorn

8-23-79

229

Puget Sound

X79-9

U.S. Oil & Refining Co.

Tacoma

2-2-79

230

S. Central WA

X77-04

Boise Cascade

Wallula

12-14-77

 

SO2

AQCR

AQCR Name

PSD #

Applicant

City

Date

062

E. WA-Idaho

None

Washington State University

Pullman

8-31-79

193

Portland-SW WA

92-03

Weyerhaeuser

Longview

4-28-92

227

N. WA

X82-04

ALCOA

Wenatchee

6-28-81

228

Oly-NW WA

X80-02

Puget sound Power & Light

Pt. Whitehorn

8-23-79

229

Puget Sound

X79-9

U.S. Oil & Refining Co.

Tacoma

2-2-79

230

S. Central WA

X77-04

Boise Cascade

Wallula

12-14-77

 

NO2