Alabama Administrative Code › Title 335 - ALABAMA DEPARTMENT OF ENVIRONMENTAL MANAGEMENT › WATER DIVISION - WATER QUALITY PROGRAM › Chapter 335-6-6 - NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM › Section 335-6-6-.15 - Calculating NPDES Permit Limitations

Current through Register Vol. 42, No. 9, June 28, 2024
(1) Outfalls and Discharge Points. Permit
				discharge limitations, standards and prohibitions shall be established for each
				discharge point from the facility, except where limitations on internal waste
				streams are more appropriately used.
(2) Production Based Limitations.
(a) In the case of POTW's, permit
				limitations, standards, or prohibitions shall be calculated based on design
				flow, the Department's Water Quality Criteria, Section IV, chapter 335-6-10, 40
				CFR Part 133 (1994) secondary treatment requirements, and criteria necessary to
				achieve or maintain water quality standards for the particular receiving
				stream.
(b) Except, in the case of
				POTW's or as provided in subparagraph
				335-6-6-.15(2)(c) or
				(d), calculation of any permit limitations,
				standards, or prohibitions which are based on production (or other measure of
				operation) shall not be based upon the designed production capacity but shall
				be based upon a reasonable measure of actual production of the facility; for
				example, the production during the high month of the previous year, or the
				monthly average for the highest of the previous five years. For new sources or
				new dischargers, actual production shall be estimated using projected
				production. The time period of the measure of production shall correspond to
				the time period of the calculated permit limitation; [for example, monthly
				production shall be used to calculate average monthly discharge
				limitations].
(c) The Director may
				include a condition establishing alternate permit limitations, standards, or
				prohibitions based upon an anticipated increase, not to exceed maximum
				production capability, or decrease in production levels. Such anticipated
				increases or decreases in production must be reasonably projected to occur
				during the duration of the permit.
(d) If the Director establishes permit
				conditions under subparagraph
				335-6-6-.15(2)(c):
1. The permit shall require the permittee to
				notify the Director at least two business days prior to a month in which the
				permittee expects to operate at a level higher than the lowest production level
				identified in the permit. The notice shall specify the anticipated level and
				the period during which the permittee expects to operate at the alternate
				level. If the notice covers more than one month, the notice shall specify the
				reasons for the anticipated production level increase. New notice of discharge
				at alternate levels is required to cover a period or production level not
				covered by prior notice or, if during two consecutive months otherwise covered
				by a notice, the production level at the facility does not in fact meet the
				higher level designated in the notice;
2. The permittee shall comply with the
				limitations, standards, or prohibitions that correspond to the lowest level of
				production specified in the permit, unless the permittee has notified the
				Director under subparagraph
				335-6-6-.15(2)(d)1.,
				in which case the permittee shall comply with the level specified in the
				notice; and
3. The permittee shall
				submit with the DMR the level of production that actually occurred during each
				month and the limitations, standards, or prohibitions applicable to that level
				of production.