Most new sources that require a Permit to Operate (PTO) are required to install Best Available Control Technology, or BACT. BACT is a pollution control standard that determines what air pollution control technology will be used to control a specific pollutant within a specified limit. BACT is typically proposed by the project applicant during the permitting phase of the project, but is subject to determination and approval by the air quality permitting agency before issuance of the operating permit. Although BACT is always determined by the agency, the proposed project must identify all applicable emission standards during the CEQA impact review, including applicable control technology requirements. Therefore, it is critical that the project description accurately identify the equipment in terms of size, throughput, and emissions to determine the appropriate emission standards and control requirements.