Continuous Emissions Monitoring Systems (CEMS)
CEMS are comprised of several components used to retrieve continuous data on pollutants emitted from a specific emissions source. EPA requires industrial facilities to install and maintain CEMS to ensure compliance with certain air quality standards set by EPA, such as New Source Performance Standards (NSPS) and National Emission Standards for Hazardous Air Pollutants (NESHAP). Cornerstone currently uses CEMS to monitor sulfur dioxide, nitrogen oxides, carbon monoxide and oxygen from designated emissions sources.
A performance test, also known as a stack test, is a method used to determine if a source is complying with an air quality standard or permit limit. Performance tests involve measuring the amount of a pollutant emitted by a specific piece of equipment or process over a designated period of time to verify compliance. EPA prescribed test methods are used to provide consistency and uniformity in assessing the effectiveness of emissions controls and measure the amount of a pollutant emitted from a source. Cornerstone conducts performance tests for criteria pollutants for various emissions sources as required by applicable standards and air permits.
Performance Tests
Parametric monitoring and other process data are also used to ensure compliance with air standards and permit limits. Parametric monitoring evaluates parameters related to the proper operation of equipment or processes rather than directly measuring emissions. Monitored parameters include temperature, pressure and flow rate of a process or emissions source and visible emissions readings. Other process data is also frequently evaluated at Cornerstone to ensure the proper operation of equipment and compliance with permitted emissions limits.