SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT
RULE 464 - WASTEWATER SEPARATORS
(Adopted May 7, 1976)(Amended September 1, 1978)(Amended April 6, 1979)
(Amended April 4, 1980)(Amended December 7, 1990)
For the purpose of this rule, the following definitions shall apply:
- WASTEWATER SEPARATOR is a wastewater treatment equipment used to separate petroleum-derived compounds from
wastewater, which includes separator basins, skimmers, grit chambers, and sludge hoppers.
- WASTEWATER SEPARATOR FOREBAY is that section of a gravity-type separator which (a) receives the untreated,
contaminated wastewater from the preseparator flume, and (b) acts as a header which distributes the influen4 to
the separator channels.
- A person shall not use any compartment of any vessel or device operated for the recovery of oil or tar from
effluent water from any equipment which processes, refines, stores or handles petroleum or coal tar products unless
such compartment is equipped with one of the following vapor loss control devices:
(A). a solid cover with all openings sealed and totally enclosing the liquid contents of the compartment; or
(B). a floating pontoon or double-deck type cover, equipped with closure seals that have no tears or leaks,
installed and maintained so the gaps between the compartment wall and the seal shall not exceed 0.32 centimeter
(1/8 inch) for an accumulative length of 97 percent of the perimeter of the compartment. No gap between the compartment
wall and the seal shall exceed 1.3 centimeters (1/2 inch).
- Any gauging and sampling device in the compartment cover shall be equipped with a cover or lid. The cover shall
be in a closed position at all times, except when the device is in actual use. There shall be no visible gaps between
the cover and the compartment when the cover is closed.
- All wastewater separator forebays shall be covered.
- Skimmed oil or tar removed from wastewater separating devices shall be either charged to process units with
feed or transferred to a container approved by the Executive Officer. A Permit to Operate issued for the container
in such service shall be considered to be approval by the Executive Officer.
This rule shall not apply to:
- gravity type wastewater separators used exclusively in conjunction with the production of crude oil if the
water fraction of the wastewater entering the separator contains less than 5 ppm hydrogen sulfide, organic sulfides,
or a combination thereof, and less than 100 ppm ammonia.
- all units which handle only coal tar products with a true vapor pressure of less than 10 mm Hg (0.2 pound per
square inch) at 60oF.
- any compartment of a wastewater separator for which the operator has demonstrated to the satisfaction of the
Executive Officer that compliance with section (b) will cause the value of
------- to exceed 420
f x V
A is the area to be covered in square feet.
V is the oil recovery rate in gallons/day on an annual basis.
f is the estimated fractional volume loss of oil and is computed as:
f = - 0.0663 + 0.000319 x (annual mean ambient temperature, oF)
- 0.000286 x (10% true boiling point, oF)
+ 0.00215 x (annual average influent temperature, oF)
The provisions of subsection (c)(3) shall not apply to coal tar wastewater separators.