There are no control requirements for an existing non-industrial POTW treatment plant. There are no control requirements for any new or reconstructed area source non-industrial POTW treatment plant which is not a major source of HAP. The control requirements for a new or reconstructed major source non-industrial POTW treatment plant which is a major source of HAP are as follows:
(a) Covers on the emission points up to, but not including, the secondary influent pumping station or the secondary treatment units. These emission points are treatment units that include, but are not limited to, influent waste stream conveyance channels, bar screens, grit chambers, grinders, pump stations, aerated feeder channels, primary clarifiers, primary effluent channels, and primary screening stations. In addition, all covered units, except primary clarifiers, must have the air in the headspace ducted to a control device in accordance with the standards for closed-vent systems and control devices in Sec. 63.693 of subpart DD of this part, except you may substitute visual inspections for leak checks rather than Method 21 of Appendix A of part 60 of this chapter. Reconstruction is defined in Sec. 63.1595.
(1) Covers must be tightly fitted and designed and operated to minimize exposure of the wastewater to the atmosphere. This includes, but is not limited to, the absence of visible cracks, holes, or gaps in the roof sections or between the roof and the supporting wall; broken, cracked, or otherwise damaged seals or gaskets on closure devices; and broken or missing hatches, access covers, caps, or other closure devices.
(2) If wastewater is in a treatment unit, each opening must be maintained in a closed, sealed position, unless plant personnel are present and conducting wastewater or sludge sampling, or equipment inspection, maintenance, or repair.
(b) As an alternative to the requirements in paragraph (a) of this section, you may comply by demonstrating, for all units up to the secondary influent pumping station or the secondary treatment units, that the fraction emitted does not exceed 0.014. You must demonstrate that for your POTW, the sum of all HAP emissions from those units divided by the sum of all HAP mass loadings results in an annual rolling average of the fraction emitted no greater than 0.014. You may use any combination of pretreatment, wastewater treatment plant modifications, and control devices to achieve this performance standard; however, you must demonstrate, to the Administrator's satisfaction that:
(1) You have accurately determined your POTW's annual HAP mass loadings and your POTW's annual HAP emissions as of the date of start-up;
(2) Your POTW meets the fraction emitted standard of 0.014 or less; and
(3) Your POTW has established procedures to demonstrate continuous compliance which are consistent with the criteria set forth in Sec. 63.1588(c)(4). [64 FR 57579, Oct. 26, 1999, as amended at 66 FR 16142, Mar. 23, 2001; 67 FR 64746, Oct. 21, 2002]