a) General Requirements

1. 1) Each PAL permit must contain enforceable requirements for the monitoring system that accurately determines plantwide emissions of the PAL pollutant in terms of mass per unit of time, or in CO₂e per unit of time for a GHG PAL. Any monitoring system authorized for use in the PAL permit must be based on sound science and meet generally acceptable scientific procedures for data quality and manipulation. Additionally, the information generated by such system must meet minimum legal requirements for admissibility in a judicial proceeding to enforce the PAL permit.
2. 2) The PAL monitoring system must employ one or more of the four general monitoring approaches meeting the minimum requirements set forth in subsection (b) and must be approved by the Agency.
3. 3) Notwithstanding subsection (a)(2), the owner or operator may also employ an alternative monitoring approach that meets subsection (a)(1) if approved by the Agency.
4. 4) Failure to use a monitoring system that meets the requirements of this Section renders the PAL invalid.

b) Minimum Performance Requirements for Approved Monitoring Approaches. The following are acceptable general monitoring approaches when conducted in accordance with the minimum requirements in subsections (c) through (i):

1. 1) Mass balance calculations for activities using coatings or solvents;
2. 2) CEMS;
3. 3) CPMS or PEMS; and
4. 4) Emission factors.

c) Mass Balance Calculations. An owner or operator using mass balance calculations to monitor PAL pollutant emissions from activities using coating or solvents shall meet the following requirements:

1. 1) Provide a demonstrated means of validating the published content of the PAL pollutant that is contained in or created by all materials used in or at the emissions unit;
2. 2) Assume that the emissions unit emits all of the PAL pollutant that is contained in or created by any raw material or fuel used in or at the emissions unit, if it cannot otherwise be accounted for in the process; and
3. 3) When the vendor of a material or fuel, that is used in or at the emissions unit, publishes a range of pollutant content from that material, the owner or operator must use the highest value of the range to calculate the PAL pollutant emissions unless the Agency determines there is site-specific data or a site-specific monitoring program to support another content within the range.

d) CEMS. An owner or operator using CEMS to monitor PAL pollutant emissions shall meet the following requirements:

1. 1) CEMS must comply with applicable Performance Specifications found in 40 CFR 60, appendix B (incorporated by reference in Section 204.100); and
2. 2) CEMS must sample, analyze and record data at least every 15 minutes while the emissions unit is operating.

e) CPMS or PEMS. An owner or operator using CPMS or PEMS to monitor PAL pollutant emissions shall meet the following requirements:

1. 1) The CPMS or the PEMS must be based on current site-specific data demonstrating a correlation between the monitored parameter or parameters and the PAL pollutant emissions across the range of operation of the emissions unit; and
2. 2) Each CPMS or PEMS must sample, analyze, and record data at least every 15 minutes, or at another less frequent interval approved by the Agency, while the emissions unit is operating.

f) Emission Factors. An owner or operator using emission factors to monitor PAL pollutant emissions shall meet the following requirements:

1. 1) All emission factors shall be adjusted, if appropriate, to account for the degree of uncertainty or limitations in the factors' development;
2. 2) The emissions unit shall operate within the designated range of use for the emission factor, if applicable; and
3. 3) If technically practicable, the owner or operator of a significant emissions unit that relies on an emission factor to calculate PAL pollutant emissions shall conduct validation testing to determine a site-specific emission factor within 6 months after PAL permit issuance, unless the Agency determines that testing is not required.

h) Notwithstanding the requirements of subsections (c) through (g), when an owner or operator of an emissions unit cannot demonstrate a correlation between the monitored parameter or parameters and the PAL pollutant emissions rate at all operating points of the emissions unit, the Agency shall, at the time of permit issuance:

1. 1) Establish a default value or values for determining compliance with the PAL based on the highest potential emissions reasonably estimated at the operating point or points; or
2. 2) Determine that operation of the emissions unit during operating conditions when there is no correlation between monitored parameter or parameters and the PAL pollutant emissions is a violation of the PAL.