|(a) A submerged biological contactor (SBC) may be used
in conjunction with other treatment systems.
(b) An SBC may be used as a roughing unit, as described
in §217.182(b)(1) of this title (relating to Trickling Filters--General
Requirements), in series with activated sludge.
(c) SBC units may be installed in existing activated
sludge basins to create a combination of fixed and suspended growth
(d) If a dual treatment system employs an SBC, the
engineering report must include supporting data, calculations, process
descriptions, and vendor information to describe how the proposed
dual treatment system will provide the required treatment levels.
(e) These designs may be subject to the requirements
of §217.7(b)(2) of this title (relating to Types of Plans and