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Air Emission Measurement Center (EMC)

Performance Specifications and Other Monitoring Information

This page includes information related to Performance Specifications and other monitoring information.

This other monitoring information includes:

Performance Specifications

Performance specifications are used for evaluating the acceptability of the CEMS at the time of or soon after installation and whenever specified in the regulations. Quality assurance procedures in 40 CFR Part 60 Appendix F are used to evaluate the effectiveness of quality control (QC) and quality assurance (QA) procedures and the quality of data produced by any CEMS that is used for determining compliance with the emission standards on a continuous basis as specified in the applicable regulation.

Performance Specifications are divided into:

Other Monitoring Information

Continuous Emission Monitoring

A continuous emission monitoring system (CEMS) is the total equipment necessary for the determination of a gas or particulate matter concentration or emission rate using pollutant analyzer measurements and a conversion equation, graph, or computer program to produce results in units of the applicable emission limitation or standard. CEMS are required under some of the EPA regulations for either continual compliance determination or determination of exceedances of the standards. The individual subparts of the EPA rules specify the reference methods that are used to substantiate the accuracy and precision of the CEMS. A predictive emission monitoring system (PEMS) is the total equipment necessary for the determination of a gas concentration or emission rate using processor control device operating parameter measurements and a conversion equation, a graph, or computer program to produce results in units of the applicable emission limitation or standard. A performance specification for PEMS, Performance Specification 16, was finalized in March of 2009.

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Compliance Assurance Monitoring

The Compliance Assurance Monitoring, or CAM, rule is designed to satisfy the requirements for monitoring and compliance certification in the Part 70 operating permits program and Title VII of the 1990 Clean Air Act Amendments. The CAM rule includes a new Part 64 and associated revisions to the Part 70 (permits program) monitoring and compliance certification requirements. The rule would establish criteria that define the monitoring, reporting, and record keeping that should be conducted by a source to provide a reasonable assurance of compliance with emission limitations and standards. These criteria address defining the applicable monitoring approach, obligation to complete corrective actions as indicated by the monitoring results, and how such data are used in the annual compliance certification. The applicable monitoring approach for any operation or facility depends on the control technology used to meet the applicable emission limit and includes monitoring of operational and control device parameters indicative of pollution control performance and record keeping of work practice and inspection procedures necessary to assure compliance operation. The final CAM Rule was published in the Federal Register on October 22, 1997.

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Metals and Mercury Emissions Monitoring

Metals Monitoring: In 1996 Performance Specification 10 (PDF) 11 pp, 43K, 1996) was proposed in conjunction with the original Hazardous Waste Combustor NESHAP, but because the measurement technology had not been fully developed and demonstrated, the specification was not promulgated. More recently, EPA has evaluated, at several facilities, a commercial version of an x-ray fluorescence metals CEMS capable of measuring most of the MACT hazardous metals in nearly real time (the instrument was built by a small business instrument developer, Cooper Environmental). Eli Lilly Company received approval from the EPA to use this instrument as a CEMS as an alternative in lieu of parameter monitoring on a hazardous waste incinerator. Lilly invested in much laboratory and field work to prove to the EPA that their CEMS is accurate, reliable, and verifiable. The US Army has successfully installed and evaluated one of these CEMS on a hazardous waste incinerator. These studies resulted in several monitoring methods and performance standards for the x-ray technology. These documents may be found under the Other Methods section of this web site.

The EMC is presently evaluating ambient fence line multimetals monitoring for compliance determination, ambient health exposure studies, and for locating and evaluating unknown sources of metals emissions. The knowledge gained from, and the success of, the Lilly study has provided support in the transition to a study of the fence line monitoring platform of this x-ray fluorescence technology. A stakeholder group has been formed to provide feedback to EMC on the project. A validation field study is underway in Missouri to compare the fence line monitor to existing PM-10 ambient monitors.

Mercury Monitoring: Like Performance Specification 10, Performance Specification 12 for mercury (Hg) CEMS was also proposed in conjunction with the original Hazardous Waste Combustor NESHAP, but because the measurement technology was not fully developed nor demonstrated at that time, it was never promulgated. Between 2003 and 2005, Performance Specification 12A for Hg CEMS was proposed and promulgated in conjunction with the Clean Air Mercury Rule (CAMR) after extensive demonstration of Hg CEMS and identification of appropriate performance parameters. In 2007, CAMR was vacated by the DC Circuit Court, which called into question the legality of using Performance Specification 12A. It has since been re-proposed in conjunction with amendments to the Portland Cement NESHAP.

In order to obtain high quality mercury monitoring data, it is necessary to have Hg calibration gas standards of known concentration and known uncertainty. EPA's Clean Air Markets Division, working with EPA's Office of Research and Development and EMC, have recently completed two interim EPA traceability protocols to establish procedures for the qualification and certification of elemental and oxidized Hg gas generators.

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