; (2) major sources or area sources identified in the most recent National Emissions Inventory of the Environmental Protection Agency as emitting ethylene oxide, chloroprene, 1–3 butadiene, benzene, or formaldehyde; (3) chemical, petrochemical, or plastics manufacturing sources or marine vessel loading operations; and (4) any other major sources of fugitive hazardous air pollutant emissions for which the Environmental Protection Agency is subject to a court-ordered or statutory deadline, engaged in a reconsideration proceeding, or subject to a court remand to, not later than 2 years after the date of enactment of this Act, review and determine whether to revise the emissions standards that apply to such sources. (c) Determination of best available form of monitoring The Administrator, in consultation with the Office of Air Quality Planning and Standards, the Office of Enforcement and Compliance Assurance, and the Office of Environmental Justice, shall, for purposes of the regulations promulgated pursuant to subsection (a), determine the best available form of continuous emissions monitoring and fenceline monitoring and shall ensure the methods required are at least as stringent as Method 325A and Method 325B. (d) Methods and technologies For all stationary sources in the source categories under subsection (b), the Administrator shall, in the regulations promulgated pursuant to subsection (a)— (1) require application, implementation, or employment of— (A) Method TO–15 or optical remote sensing technology to provide real-time measurements of air pollutant concentrations along an open-path; or (B) other monitoring technology with the ability to provide real-time spatial and temporal data to understand the type and amount of emissions