Statutes, codes, and regulations
Delaware Administrative Code
Title 7 - Natural Resources and Environmental ControlAir Quality Management SectionDivision of Air Quality
Requirements for Preconstruction Review
Section 1125-3.0 - Prevention of Significant Deterioration of Air Quality

7 Del. Admin. Code § 1125-3.0

Download
PDF
Current through Register Vol. 28, No. 7, January 1, 2025
Section 1125-3.0 - Prevention of Significant Deterioration of Air Quality
3.1 Definitions - For the purposes of Section 3.0 of this regulation:

"Major Stationary Source" means:

* Any of the following stationary sources of air pollutants which emits or has the potential to emit, 100 tons per year or more of any pollutant subject to regulation under the CAA: Fossil fuel-fired steam electric plants of more than 250 million British thermal units per hour heat input, coal cleaning plants (with thermal dryers), kraft pulp mills, portland cement plants, primary zinc smelters, iron and steel mill plants, primary aluminum ore reduction plants, primary copper smelters, municipal incinerators capable of charging more than 250 tons of refuse per day, hydrofluoric, sulfuric, and nitric acid plants, petroleum refineries, lime plants, phosphate rock processing plants, coke oven batteries, sulfur recovery plants, carbon black plants (furnace process), primary lead smelters, fuel conversion plants, sintering plants, secondary metal production plants, chemical process plants, fossil fuel boilers (or combinations thereof) totaling more than 250 million British thermal units per hour heat input, petroleum storage and transfer units with a total storage capacity exceeding 300,000 barrels, taconite ore processing plants, glass fiber processing plants, and charcoal production plants;

* Notwithstanding the stationary source size specified in the above paragraph, any stationary source which emits, or has the potential to emit, 250 tons per year or more of any air pollutant subject to regulation under the CAA; or

* Any physical change that would occur at a stationary source not otherwise qualifying under the preceding paragraph as a major stationary source, if the change would constitute a major stationary source by itself.

A major stationary source that is major for volatile organic compounds or nitrogen oxides shall be considered major for ozone.

3.2 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 (Micrograms per cubic meter) Class I
Pollutant
Total suspended particulates:
Annual geometric mean 5
24-hour maximum 10
Sulfur dioxide:
Annual arithmetic mean 2
24-hour maximum 5
Three-hour maximum 25
PM2.5:
Annual arithmetic mean 1
24-hr maximum 2
PM10:
Annual arithmetic mean 4
24-hr maximum 8
Nitrogen dioxide
Annual arithmetic mean 2.5
Class II
Pollutant
Total suspended particulates:
Annual geometric mean 19
24-hour maximum 37
Sulfur dioxide:
Annual arithmetic mean 20
24-hour maximum 91
Three-hour maximum 512
PM2.5:
Annual arithmetic mean 4
24-hr maximum 9
PM10:
Annual arithmetic mean 17
24-hr maximum 30
Nitrogen dioxide
Annual arithmetic mean 25
Class III
Pollutant
Total suspended particulates:
Annual geometric mean 37
24-hour maximum 75
Sulfur dioxide:
Annual arithmetic mean 40
24-hour maximum 182
Three-hour maximum 700
PM2.5:
Annual arithmetic mean 8
24-hr maximum 18
PM10:
Annual arithmetic mean 34
24-hr maximum 60
Nitrogen dioxide
Annual arithmetic mean 50

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.

3.3 Ambient Air Ceilings. No concentration of a pollutant shall exceed:
3.3.1 The concentration permitted under the national secondary ambient air quality standard, or
3.3.2 The concentration permitted under the national primary ambient air quality standard, whichever concentration is lowest for the pollutant for a period of exposure.
3.4 Restrictions on Area Classification.
3.4.1 All Areas in the State of Delaware are designated Class II, but may be redesignated as provided in 40 CFR 52.51(g).
3.4.2 The following areas may be redesignated only as Class I:
3.4.2.1 Bombay Hook National Wildlife Refuge; and
3.4.2.2 A national park or national wilderness area established after August 7, 1977 which exceeds 10,000 acres in size.
3.5 Exclusions from Increment Consumption
3.5.1 Upon written request of the governor, made after notice and opportunity for at least one public hearing to be held in accordance with procedures established by the State of Delaware, the Department shall exclude the following concentrations in determining compliance with a maximum allowable increase:
3.5.1.1 Concentrations attributable to the increase in emissions from stationary sources which have converted from the use of petroleum products, natural gas, or both by reason of an order in effect under sections 2(a) and 2(b) of the Energy Supply and Environmental Coordination Act of 1974 (or any superseding legislation) over the emissions from such sources before the effective date of such an order;
3.5.1.2 Concentrations attributable to the increase in emissions from sources which have converted from using natural gas by reason of a 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;
3.5.1.3 Concentrations of particulate matter attributable to the increase in emissions from construction or other temporary emission-related activities of new or modified sources;
3.5.2 No exclusion of such concentrations shall apply more than five years after the effective date of the order to which subsection 3.5.1.1 of this regulation refers or the plan to which subsection 3.5.1.2 of this regulation refers, whichever is applicable. If both such order and plan are applicable, no such exclusion shall apply more than five years after the later of such effective dates.
3.6 Stack Heights

The provisions of 7 DE Admin. Code 1127 - STACK HEIGHTS, are applicable to subsection 3.6 of this regulation.

3.7 Review of Major Stationary Sources and Major Modifications - Source Applicability and Exemptions.
3.7.1 No stationary source or modification to which the requirements of subsection 3.8 through subsection 3.15 of this regulation apply shall begin actual construction without a permit which states that the stationary source or modification would meet those requirements. The Department has authority to issue any such permit.
3.7.2 The requirements of subsection 3.8 through subsection 3.15 of this regulation shall apply to any major stationary source and any major modification with respect to each pollutant subject to regulation under the CAA that it would emit, except as Section 3.0 of this regulation otherwise provides.
3.7.3 The requirements of subsection 3.8 through subsection 3.15 of this regulation apply only to any major stationary source or major modification that would be constructed in an area designated as attainment or unclassifiable.
3.7.4 The requirements of subsection 3.8 through subsection 3.15 of this regulation shall not apply to a particular major stationary source or major modification, if:
3.7.4.1 The source or modification would be a nonprofit health or nonprofit educational institution, or a major modification would occur at such an institution, and the governor requests that it be exempt from those requirements; or
3.7.4.2 The source or modification would be a major stationary source or major modification only if fugitive emissions, to the extent quantifiable, are considered in calculating the potential to emit of the stationary source or modification and the source does not belong to any of the following categories:
3.7.4.2.1 Coal cleaning plants (with thermal dryers);
3.7.4.2.2 Kraft pulp mills;
3.7.4.2.3 Portland cement plants;
3.7.4.2.4 Primary zinc smelters;
3.7.4.2.5 Iron and steel mills;
3.7.4.2.6 Primary aluminum ore reduction plants;
3.7.4.2.7 Primary copper smelters;
3.7.4.2.8 Municipal incinerators capable of charging more than 250 tons of refuse per day;
3.7.4.2.9 Hydrofluoric, sulfuric, or nitric acid plants;
3.7.4.2.10 Petroleum refineries;
3.7.4.2.11 Lime plants;
3.7.4.2.12 Phosphate rock processing plants;
3.7.4.2.13 Coke oven batteries;
3.7.4.2.14 Sulfur recovery plants;
3.7.4.2.15 Carbon black plants (furnace process);
3.7.4.2.16 Primary lead smelters;
3.7.4.2.17 Fuel conversion plants;
3.7.4.2.18 Sintering plants;
3.7.4.2.19 Secondary metal production plants;
3.7.4.2.20 Chemical process plants;
3.7.4.2.21 Fossil-fuel boilers (or combination thereof) totaling more than 250 million British thermal units per hour heat input:
3.7.4.2.22 Petroleum storage and transfer units with a total storage capacity exceeding 300,000 barrels;
3.7.4.2.23 Taconite ore processing plants;
3.7.4.2.24 Glass fiber processing plants;
3.7.4.2.25 Charcoal production plants;
3.7.4.2.26 Fossil fuel-fired steam electric plants of more than 250 million British thermal units per hour heat input;
3.7.4.2.27 Any other stationary source category which, as of August 7, 1980, is being regulated under section 111 or 112 of the CAA; or
3.7.4.3 The source is a portable stationary source which has previously received a permit under Section 3.0 of this regulation, and,
3.7.4.3.1 The owner or operator proposal to relocate the source and emissions of the source at the new location would be temporary; and
3.7.4.3.2 The emissions from the source would not exceed its allowable emissions; and
3.7.4.3.3 The emissions from the source would impact no Class I area and no area where an applicable increment is known to be violated; and
3.7.4.3.4 Reasonable notice is given to the Department prior to the relocation identifying the proposed new location and the probable duration of operation at the new location. Such notice shall be given to the Department not less than 10 days in advance of the proposed relocation unless a different time duration is previously approved by the Department.
3.7.5 The requirements of subsection 3.8 through subsection 3.15 of this regulation shall not apply to a major stationary source or major modification with respect to a particular pollutant if the owner or operator demonstrates that, as to that pollutant, the source or modification is located in an area designated as non-attainment.
3.7.6 The requirements of subsection 3.9, subsection 3.11, and subsection 3.13 of this regulation shall not apply to a major stationary source or major modification with respect to a particular pollutant, if the allowable emissions of that pollutant from the source, or the net emissions increase of that pollutant from the modification:
3.7.6.1 Would impact no Class I area and no area where an applicable increment is known to be violated, and
3.7.6.2 Would be temporary.
3.7.7 The Department may exempt a stationary source or modification from the requirements of subsection 3.11 of this regulation with respect to monitoring for a particular pollutant if:
3.7.7.1 The emissions increase of the pollutant from the new source or the net emissions increase of the pollutant from the modification would cause, in any area, air quality impacts less than the following amounts:

Carbon monoxide: 575 ug/m3, eight-hour average;

Nitrogen dioxide: 14 ug/m3, annual average;

Total suspended particulate: 10 ug/m3, 24-hour average;

Sulfur dioxide: 13 ug/m3, 24-hour average;

Ozone: (See Note 1)

Lead: 0.1 ug/m3, 3-month average;

Mercury: 0.25 ug/m3, 24-hour average;

Beryllium: 0.0005 ug/m3, 24-hour average;

Fluorides: 0.25 ug/m3, 24-hour average;

Vinyl chloride: 15 ug/m3, 24-hour average;

Total reduced sulfur: 10 ug/m3, one-hour average;

Hydrogen sulfide: 0.04 ug/m3, one-hour average;

Reduced sulfur compounds: 10 ug/m3, one-hour average;

PM10 particulate: 10 ug/m3, 24-hour average

PM2.5: 4 µg/m3, 24-hour average

[Note 1: No de minimus air quality level is provided for ozone. However, any net increase of 100 tons per year or more of volatile organic compounds or nitrogen oxides subject to PSD would be required to perform an ambient impact analysis including the gathering of ambient air quality data.]

3.7.7.2 The concentrations of the pollutant in the area that the source or modification would affect are less than the concentrations listed in subsection 3.7.7.1 of this regulation, or the pollutant is not listed in subsection 3.7.7.1 of this regulation.
3.8 Control Technology Review
3.8.1 A major stationary source or major modification shall meet each applicable emissions limitation of the State of Delaware's Air Pollution Control Regulations.
3.8.2 A new major stationary source shall apply best available control technology for each pollutant subject to regulation under the CAA that it would have the potential to emit in significant amounts.
3.8.3 A major modification shall apply best available control technology for each pollutant subject to regulation under the CAA for which it would result in a significant net emissions increase at the source. This requirement applies to each proposed emissions unit at which a net emissions increase in the pollutant would occur as a result of a physical change or change in the method of operation in the unit.
3.8.4 For phase construction projects, the determination of best available control technology shall be reviewed and modified as appropriate at the latest reasonable time which occurs no later than 18 months prior to commencement of construction of each independent phase of the project. At such time, the owner or operator of the applicable stationary source may be required to demonstrate the adequacy of any previous determination of best available control technology for the source.
3.9 Source Impact Analysis.
3.9.1 The owner or operator of the proposed source or modification shall demonstrate that allowable emission increases from the proposed source or modification, in conjunction with all other applicable emissions increases or reductions (including secondary emissions), would not cause or contribute to air pollution in violation of:

* Any national ambient air quality standard in any air quality control region; or

* Any applicable maximum allowable increase over the baseline concentration in any area.

3.9.2 The demonstration required in subsection 3.9.1 of this regulation will be deemed to have been made if the emissions increase from the new stationary source alone or the modification alone would cause, in all areas, air quality impacts less than the following significant impact levels:

Significant Impact Level
Pollutant Averaging Time Class I Class II Class III
PM2.5 Annual 0.06 0.3 0.3
24-hour 0.07 1.2 1.2

3.10 Air Quality Models.
3.10.1 All estimates of ambient concentrations required under Section 3.0 of this regulation shall be based on the applicable air quality models, databases, and other requirements specified in the "Guideline on Air Quality Models" ( 40 CFR Part 51, Appendix W (July 1, 2018 ed.). This document is incorporated by reference.
3.10.2 When an air quality impact model specified in the "Guideline on Air Quality Models" is inappropriate, the model may be modified or another model substituted. Such a change must be subject to the notice and opportunity for public comment under subsection 3.14 of this regulation. Written approval of the Department must be obtained for any modification or substitution. Changes are also subject to the requirements specified in 40 CFR Part 51, Appendix W for evaluation and approval of alternative models.
3.11 Air Quality Analysis
3.11.1 Preapplication Analysis.
3.11.1.1 Any application for a permit under Section 3.0 of this regulation shall contain an analysis of ambient air quality in the area that the major stationary source or major modification would affect for each of the following pollutants:
3.11.1.1.1 For the source, each pollutant that it would have the potential to emit in a significant amount;
3.11.1.1.2 For the modification, each pollutant for which it would result in a significant net emissions increase.
3.11.1.2 With respect to any such pollutant for which no National Ambient Air Quality Standard exists, the analysis shall contain such air quality monitoring data as the Department determines is necessary to assess ambient air quality for that pollutant in any area that the emissions of that pollutant would affect.
3.11.1.3 With respect to any such pollutant (other than non-methane hydrocarbons) for which such a standard does exist, the analysis shall contain continuous air quality monitoring data gathered for purposes of determining whether emissions of that pollutant would cause or contribute to a violation of the standard or any maximum allowable increase.
3.11.1.4 In general, the continuous air quality monitoring data that is required shall have been gathered over a period of at least one year and shall represent at least the year preceding receipt of the application, except that, if the Department determines that a complete and adequate analysis can be accomplished with monitoring data gathered over a period shorter than one year (but not to be less than four months), the data that is required shall have been gathered over at least that shorter period.
3.11.1.5 The owner or operator of a proposed stationary source or modification of volatile organic compounds or nitrogen oxides who satisfies all of the following conditions may provide post-approval monitoring data for ozone in lieu of providing preconstruction data as required under subsection 3.11.1 of this regulation.

Condition 1: The new source is required to meet an emission limitation which specifies the lowest achievable emission rate for such source.

Condition 2: The applicant must certify that all existing major sources owned or operated by the applicant (or any entity controlling, controlled by, or under common control with the applicant) in Delaware are in compliance with all applicable emission limitations and standards under the CAA (or are in compliance with an expeditious schedule approved by the Department).

Condition 3: Emission reductions ("offsets") from existing sources in the area of the proposed source (whether or not under the same ownership) are required such that there will be reasonable progress toward attainment of the applicable NAAQS. Only intrapollutant emission offsets will be acceptable (e.g., hydrocarbon increases may not be offset against SO2 (reductions)).

Condition 4: The emission offsets will provide a positive net air quality benefit in the affected area (see 40 CFR Part 51 App. S). Atmospheric simulation modeling is not necessary for volatile organic compounds and NOx. Fulfillment of Condition 3 will be considered adequate to meet this condition for volatile organic compounds and NOx.

3.11.2 Post-construction monitoring. The owner or operator of a major stationary source or major modification shall, after construction of the stationary source or modification conduct such ambient monitoring as the Department determines is necessary to determine the effect emissions from the stationary source or modification may have, or are having, on air quality in any area.
3.11.3 Operations of monitoring stations. The owner or operator of a major stationary source or major modification shall meet the Quality Assurance Requirements for PSD Air Monitoring as preapproved by the Department during the operation of monitoring stations for purposes of satisfying subsection 3.11 of this regulation.
3.12 Source Information. The owner or operator of proposed source or modification shall submit all information necessary to perform any analysis or make any determination required under Section 3.0 of this regulation.
3.12.1 With respect to a source or modification to which subsection 3.9, subsection 3.11, and subsection 3.13 of this regulation apply, such information shall include but not be limited to:
3.12.1.1 A description of the nature, location, design capacity and typical operating schedule of the source or modification, including specifications and drawings showing its design and plant layout;
3.12.1.2 A detailed schedule for construction of the source or modification;
3.12.1.3 A detailed description as to what system of continuous emission reduction is planned for the source or modification, emission estimates, and any other information necessary to determine that best available control technology would be applied.
3.12.2 Upon request of the Department, the owner or operator shall also provide information on:
3.12.2.1 The air quality impact of the source or modification, including meteorological and topographical data necessary to estimate such impact; and
3.12.2.2 The air quality impacts, and the nature and extent of any or all general commercial, residential, industrial, and other growth which has occurred since August 7, 1977 or the applicable baseline date or dates, in the area the source or modification would affect.
3.13 Additional Impact Analyses.
3.13.1 The owner or operator shall provide an analysis of the impairment to visibility, soils and vegetation that would occur as a result of the source or modification and general commercial, residential, industrial and other growth associated with the source or modification. The owner or operator need not provide an analysis of the impact on vegetation having no significant commercial or recreational value.
3.13.2 The owner or operator shall provide an analysis of the air quality impact projected for the area as a result of general commercial, residential, industrial and other growth associated with the source or modification.
3.14 Public Participation
3.14.1 Within 30 days after receipt of an application to construct, or any addition to such application, the Department shall advise the applicant of any deficiency in the application or in the information submitted. In the event of such a deficiency, the date of receipt of the application shall be, for the purpose of Section 3.0 of this regulation, the date on which the Department received all required information.
3.14.2 Within one year after receipt of a complete application, the Department shall make a final determination on the application. This involves performing the following actions in a timely manner:
3.14.2.1 Make a preliminary determination whether construction should be approved, approved with conditions, or disapproved.
3.14.2.2 Make available a copy of all materials the applicant submitted, a copy of the preliminary determination, and a copy or summary of other materials, if any, considered in making the preliminary determination.
3.14.2.3 Notify the public, by advertisement in a newspaper of general circulation in each region in which the proposed source or modification would be constructed, of the application, the preliminary determination, the degree of increment consumption that is expected from the source or modification, and the opportunity for comment at public hearing as well as written public comment.
3.14.2.4 Send a copy of the notice of public comment to the applicant and to officials and agencies having cognizance over the location where the proposed construction would occur as follows: the chief executives of the city and county where the source or modification would be located and any comprehensive regional land use planning agency whose lands may be affected by emissions from the source or modification. Additionally, if the proposed source would have significant interstate impact, the Governor of that impacted state would be notified.
3.14.2.5 Provide opportunity for a public hearing for interested persons to appear and submit written or oral comments on the air quality impact of the source or modification, alternatives to the source or modification, the control technology required, and other appropriate considerations.
3.14.2.6 Consider all written comments submitted within a time specified in the notice of public comment and all comments received at any public hearing or hearings in making a final decision on the approvability of the application. No later than 10 days after the close of the public comment period, the applicant may submit a written response to any comments submitted by the public. The Department shall consider the applicant's response in making a final decision. The Department shall make all comments available for public inspection in the same locations where the Department made available preconstruction information relating to the proposed source or modification.
3.14.2.7 Make a final determination whether construction should be approved, approved with conditions, or disapproved pursuant to Section 3.0 of this regulation.
3.14.2.8 Notify the applicant in writing of the final determination and make such notification available for public inspection at the same location where the Department made available preconstruction information and public comments relating to the source or modification.
3.15 Source Obligation.
3.15.1 Any owner or operator who constructs or operates a source or modification not in accordance with the application submitted pursuant to Section 3.0 of this regulation or with the terms of any approval to construct, or any owner or operator of a source or modification subject to Section 3.0 of this regulation who commences construction after the effective date of these regulations without applying for and receiving approval hereunder, shall be subject to appropriate enforcement action.
3.15.2 Approval to construct shall become invalid if construction is not commenced within 18 months after receipt of such approval, if construction is discontinued for a period of 18 months or more, or if construction is not completed within a reasonable time. The Department may extend the 18-month period upon a satisfactory showing that an extension is justified. This provision does not apply to the time period between constructions of the approved phases of a phased construction project; each phase must commence construction within 18 months of the projected and approved commencement date.
3.15.3 Approval to construct shall not relieve any owner or operator of the responsibility to comply fully with applicable provisions of any other requirements under local or Federal law.
3.15.4 At such time that a particular source or modification becomes a major stationary source or major modification solely by virtue of a relaxation in any enforceable limitation which was established after August 7, 1980 on the capacity of the source or modification otherwise to emit a pollutant, such as a restriction on hours of operation, then the requirements of subsection 3.8 through subsection 3.15 of this regulation shall apply to the source or modification as though construction had not yet commenced on the source or modification.
3.16 Innovative Control Technology.
3.16.1 An owner or operator of a proposed major stationary source or major modification may request the Department in writing no later than 30 days after the close of the public comment hearing to approve a system of innovative control technology.
3.16.2 The Department shall, with the consent of the Governor of Delaware, determine that the source or modification may employ a system of innovative control technology, if:
3.16.2.1 The proposed control system would not cause or contribute to an unreasonable risk to public health, welfare, or safety in its operation or function;
3.16.2.2 The owner or operator agrees to achieve a level of continuous emissions reduction equivalent to that which would have been required under subsection 3.8.2 of this regulation by a date specified by the Department. Such date shall not be later than four years from the time of startup or seven years from permit issuance;
3.16.2.3 The source or modification would meet the requirements of subsection 3.8 and subsection 3.9 of this regulation based on the emissions rate that the stationary source employing the system of innovative control technology would be required to meet on the date specified by the Department;
3.16.2.4 The source or modification would not be before the date specified by the Department:
3.16.2.4.1 Cause or contribute to a violation of an applicable national ambient air quality standard; or
3.16.2.4.2 Impact any Class I area; or
3.16.2.4.3 Impact any area where an applicable increment is known to be violated; and
3.16.2.5 All other applicable requirements including those for public participation have been met.
3.16.3 The Department shall withdraw any approval to employ a system of innovative control technology made under Section 3.0 of this regulation, if:
3.16.3.1 The proposed system fails before the specified date to achieve the required continuous emissions reduction rate; or
3.16.3.2 The proposed system fails before the specified date so as to contribute to an unreasonable risk to public health, welfare, or safety; or
3.16.3.3 The Department decides at any time that the proposed system is unlikely to achieve the required level of control or to protect the public health, welfare, or safety.
3.16.4 If a source or modification fails to meet the required level of continuous emission reduction within the specified time period or the approval is withdrawn in accordance with subsection 3.16.3 of this regulation, the Department may allow the source or modification up to an additional three years to meet the requirement for the application of best available control technology through use of a demonstrated system of control.

12/11/2016

7 Del. Admin. Code § 1125-3.0

13 DE Reg. 1345 (04/01/10)
15 DE Reg. 1169 (02/01/12)
16 DE Reg. 214 (08/01/12)
20 DE Reg. 461 (12/1/2016)
23 DE Reg. 579 (1/1/2020) (Final)