Clean Air Act Emission Limits

Transcription

1 1 Clean Air Act Emission Limits

2 CAA Emission Limits Authority for and Origin of Limits Federally promulgated regulations (e.g. NSPS, NESHAP, or MACT) SIP requirements PSD and N/A NSR permits 2

3 NSPS 3 New Source Performance Standards Authorized by section 111 of the Clean Air ACT in 1970 First NSPS subpart D for fossil fuel fired steam generating units promulgated in 1971 Industry specific technology based standards applicable to new, modified or reconstructed facilities Best Demonstrated Technology (BDT) BDT is the best system of continuous emissions reduction that has been demonstrated to work in a given industry, considering economic costs and other factors, such as energy use.

4 NESHAP and MACT 4 National Emission Standards for Hazardous Air Pollutants Section 112 of the 1970 CAA required EPA to identify and list all air pollutants (not already identified as criteria pollutants) that "may reasonably be anticipated to result in an increase in mortality or an increase in serious irreversible or incapacitating reversible illness. NESHAP standards were developed for certain pollutants that applied to certain existing sources Maximum Achievable Control Technology The 1990 CAA amendments renewed emphasis on controlling emissions of hazardous air pollutants (HAPs) from new and existing sources on the federal level by regulating a list of HAPs based on the maximum available control technology.

5 Form of limit for NSPS, NESHAP and MACT 5 The format of the standards varies by subpart numerical emission limit concentration process weight based an equipment or design standard or a work practice standard The format of the limit is defined by the rule and cannot be changed Some provision for source specific MACT but none in NSPS

6 SIPs Section 110 of the 1970 CAA required the adoption of State Implementation Plans that specify emissions controls needed for new and existing sources in an area to meet and maintain the NAAQS for the criteria pollutants: Ozone Particulate Matter Carbon Monoxide Nitrogen Oxides Sulfur Dioxide Lead Reasonably Available Control Technology (RACT) required for existing sources in nonattainment areas 6

7 Synthetic Minor Limits Synthetic minor limits are set to ensure that a source or a modification remains minor Major source threshold for PSD, N/A NSR or air toxics Major modification threshold in PSD or N/A NSR Units of measure should be mass rate based (lb/hr, tpy, etc.) 7

8 Prevention of Significant Deterioration BACT 8 Major new and modified sources in attainment areas are required to obtain a preconstruction permit and install Best Available Control Technology BACT is The maximum degree of reduction in the discharge of air pollutants (emissions) achievable through the currently available methods, systems, and techniques while taking economic, energy, environmental and other costs into consideration.

9 Non Attainment New Source Review LAER Major new and modified sources in nonattainment areas are required to install technology based on the Lowest Achievable Emission Rate LAER is the rate of emissions that reflects the more stringent of (1) the most stringent emission limitation in the implementation plan of any state for such source unless the owner or operator demonstrates such limitations are not achievable; or (2) the most stringent emissions limitation achieved in practice. 9

10 Types of Limits for BACT/LAER Numeric emissions limits (#/mmbtu, lbs/hr, tons/yr) Operational limits (hrs of operation, throughput limits, parametric limits) Work practice standards (O/M, good combustion practices) 10

11 BACT/LAER Limit Units of Measure BACT limits expressed on a concentration (ppm) or process weight (lb/ton) basis are more readily transferable than those expressed as mass rate (lb/hr and tpy) Draft 1990 NSR Workshop Manual BACT emission limits or conditions must be met on a continual basis at all levels of operation (e.g., limits written in pounds/mmbtu or percent reduction achieved), demonstrate protection of short term ambient standards (limits written in pounds/hour).. Best practice is to have both a concentation or process weight based limit and a mass rate limit. 11

12 1990 NSR Workshop Manual 12 The manual provides extensive guidance on determining BACT and LAER and covers such issues as: Calculating costs and comparing cost effectiveness Technical feasibility and technology transfer Comparing levels of performance amongst options Deciding on a level of control for technologies that have a range of control

13 RACT/BACT/LAER Information System (Clearinghouse) The RBLIS is a valuable tool that is useful in identifying control options for consideration as RACT, BACT or LAER Only as good as its inputs We should all update 13