Grease, oil and sand interceptors or traps shall be provided
when, in the opinion of the Engineer, they are necessary for the proper
handling of liquid wastes containing fats, oil and grease in excess
of the stated limits in this chapter or any flammable wastes, grit
or other harmful ingredients, except that such interceptors shall
not be required for residential dwelling or apartment units. Interceptors
shall be of a type and capacity approved by the Engineer and shall
be located as to be readily and easily accessible for cleaning and
visual inspection.
Where pretreatment or flow-equalizing structures and/or equipment
are required by permit, they shall be maintained continuously in satisfactory
and effective operation by the owner, at the owner's expense and accessible
for unannounced inspection by the Engineer.
Upon the promulgation of the Federal Categorical Pretreatment
Standards for a particular industrial subcategory, the federal standard,
if more stringent than limitations imposed under this chapter for
sources in that subcategory, shall immediately supersede the limitations
imposed under this chapter. The Engineer shall notify all affected
users of the applicable reporting requirements under 40 CFR 403.12.
Where the County's wastewater treatment system achieves consistent
removal of pollutants limited by Federal Pretreatment Standards, the
County may apply to the approval authority for modification of specific
limits in the Federal Pretreatment Standards. "Consistent removal"
shall mean reduction in the amount of a pollutant or alteration of
the nature of the pollutant by the wastewater treatment system to
a less toxic or harmless state in the effluent, which is achieved
by the system in 95% of the samples taken when measured according
to the procedures set forth in Section 403.7(c)(2) of Title 40 of
the Code of Federal Regulations, Part 403, General Pretreatment Regulations
for Existing and New Sources of Pollution, promulgated pursuant to
the Act (as may be amended). The County may then modify pollutant
discharge limits in the Federal Pretreatment Standards if the requirements
contained in 40 CFR 403.7 are fulfilled and prior approval from the
approval authority is obtained.
State requirements and limitations on discharges shall apply
in any case where they are more stringent than federal requirements
and limitations or those in this chapter.
No user shall ever increase the use of process water or in any
way attempt to dilute a discharge as a partial or complete substitute
for adequate treatment to achieve compliance with the limitations
contained in the Federal Categorical Pretreatment Standards or in
any other pollutant-specific limitation developed by the County or
state.