All ERCs not used within ten (10) years of generation will be retired as a benefit to the environment.
Safeguards built into 45CSR28 (such as for data collection and accuracy, recordkeeping, etc.) protect
sources using ERCs while adding operational flexibilty. All ERCs must be held in advance of actual use and
all appropritate notifications required by rule must be met.
A key use of ERCs in WV in the near-term is likely to be for meeting state reasonably available control
technology (RACT) and SIP requirements such as in 45CSR6, 45CSR7, 45CSR10 and 45CSR21. Emission offsets
resulting from permanent shutdowns as required by lowest achievable emission rate (LAER) standards may be
used in conjunction with data in the registry to the extent allowed by 45CSR19.
In addition to using ERCs to meet state RACT and SIP requirements, another potential use of ERCs that can
provide the regulated community with enhanced facility operating flexibility is as a compliance margin. Such
ERCs may be used as a contingency to counterbalance "unplanned" emission excursions over permitted limits.
Examples of such "unplanned" emission exceedances can result from unexpected changes in process operations,
steam or electrical output requirements or malfunction of pollution control devices, or inconsistencies in
raw material or fuel content. While persistent exceedances would be dealt with via the enforcement route,
occassional excursions from permitting limits may be eligible for using ERCs. Although holding ERCs to
provide a compliance margin for "unplanned" emission excursions is a potential use, as with all ERCs, such
credits must be held in advance of use. Therefore, the source must be able to anticipate the proposed ERC
use with enough specificity to demonstrate that any uses would neet the rule requirements.
Air quality analyses employing procedures approved by the Director must be supplied by the applicant if a
proposed ERC use will result in actual emissions or overages equivalent to the amounts set forth in
45CSR§28-4.1. If such air quality analyses involves air dispersion modeling, the standards and procedures
set forth in EPA's Guidance on Air Quality Models (GAQM) found at 40CFR51, Appendix W, are to be used. Air
dispersion modeling submittals are to be based on a protocol previously approved by DAQ.
ERCs used in an attainment area must not cause a violation of a NAAQS, a prevention of significant
deterioration (PSD) increment, or an applicable attainment area maintenance plan. The use of ERCs in a
nonattainment area must result in emissions reductions consistent with the requirements for reasonable
further progress (RFP) for the nonattainment area and the attainment demonstration specified in the SIP.