Hawaii Administrative Rules › Title 11 - DEPARTMENT OF HEALTH › Subtitle 1 - GENERAL DEPARTMENTAL PROVISIONS › Chapter 54 - WATER QUALITY STANDARDS › Section 11-54-9 - Zones of mixing

Current through June, 2024
(a) As used in this
				section, "zones of mixing" means limited areas around outfalls and other
				facilities to allow for the initial dilution of waste discharges.
(b) Zones of mixing for the assimilation of
				domestic, agricultural, and industrial discharges which have received the best
				degree of treatment or control are recognized as being necessary. It is the
				objective of these limited zones to provide for a current realistic means of
				control over the placement and manner of discharges or emissions so as to
				achieve the highest attainable level of water quality or otherwise to achieve
				the minimum environmental impact considering initial dilution, dispersion, and
				reactions from substances which may be considered to be pollutants.
(c) Establishment, renewal, and termination.
(1) Application for establishment of a zone
				of mixing shall be made concurrently with any discharge permits whenever
				applicable and the conditions of a zone of mixing shall be incorporated as
				conditions of the discharge permits. Every application for a zone of mixing
				shall be made on forms furnished by the director and shall be accompanied by a
				complete and detailed description of present conditions, how present conditions
				do not conform to standards, and other information as the director may
				prescribe.
(2) Each application for
				a zone of mixing shall be reviewed in light of the descriptions, statements,
				plans, histories, and other supporting information as may be submitted upon the
				request of the director, and in light of the effect or probable effect upon
				water quality standards established pursuant to this chapter.
(3) Whenever an application is approved, the
				director shall establish the zone of mixing, taking into account the
				environmental impact, including but not limited to factors such as the
				protected uses of the body of water, existing natural conditions of the
				receiving water, character of the effluent, and the adequacy of the design of
				the outfall and diffuser system to achieve maximum dispersion and assimilation
				of the treated or controlled waste with a minimum of undesirable or noticeable
				effect on the receiving water.
(4)
				Approval of a zone of mixing shall be made either after a public hearing is
				held by the director in the county where the source is situated, in accordance
				with chapters
				91 and
				92, HRS and the rules of practice and
				procedures of the department, or after the public notification and comment
				process duly established for a discharge permit in the case when the zone of
				mixing is being considered concurrently with the discharge permit.
(5) No zone of mixing shall be established by
				the director unless the application and the supporting information clearly show
				that:
(A) The continuation of the function or
				operation involved in the discharge by the granting of the zone of mixing is in
				the public interest;
(B) The
				discharge occurring or proposed to occur does not substantially endanger human
				health or safety;
(C) Compliance
				with the existing water quality standards from which a zone of mixing is sought
				would produce serious hardships without equal or greater benefits to the
				public; and
(D) The discharge
				occurring or proposed to occur does not violate the basic standards applicable
				to all waters, will not unreasonably interfere with any actual or probable use
				of the water areas for which it is classified, and has received (or in the case
				of a proposed discharge will receive) the best degree of treatment or
				control.
(6) Any zone of
				mixing or renewal thereof shall be established within the requirements of this
				section and for time periods and under conditions consistent with the reasons
				therefore and within the following limitations:
(A) If the zone of mixing is established on
				the grounds that there is no reasonable means known or available for the
				adequate prevention, control, or abatement of the discharge involved, it shall
				be allowed only until the necessary means for prevention, control or abatement
				become practicable, and subject to the taking of any substitute or alternative
				measures that the director may prescribe. No renewal of a zone of mixing
				established under this subsection shall be allowed without a thorough review of
				known and available means of preventing, controlling, or abating the discharge
				involved;
(B) The director may
				issue a zone of mixing for a period not exceeding five years;
(C) Every zone of mixing established under
				this section shall include, but not be limited to, conditions requiring the
				applicant to perform appropriate effluent and receiving water sampling
				including monitoring of bottom biological communities and report the results of
				each sampling to the director. A program of research to develop reasonable
				alternatives to the methods of treatment or control in use by the applicant may
				be required if research is deemed prudent by the director; and
(D) In order to prevent high temperature
				discharges from violating section
				11-54-04
				(a) (4), no new or increased domestic, industrial, or other controllable source
				shall discharge at a maximum temperature which will cause temperatures to
exceed
three degrees Celsius above ambient, or thirty degrees
				Celsius, whichever is less, within one meter of the bottom within a zone of
				mixing. For discharges with or without submerged outfalls, the director may
				make a limited allowance for higher discharge temperatures if there is
				satisfactory demonstration that the elevated temperature will not cause damage
				to the local aquatic community.
(7) Any zone of mixing established pursuant
				to this section may be renewed from time to time on terms and conditions and
				for periods not exceeding five years which would be appropriate on initial
				establishment of a zone of mixing, provided that the applicant for renewal had
				met all of the conditions specified in the immediately preceding mixing, and
				provided further that the renewal and the zone of mixing established in
				pursuance thereof shall provide for the discharge not greater in quantity of
				mass emissions than that attained pursuant to the terms of the immediately
				preceding zone of mixing at its expiration. Any new zones of mixing or requests
				for zone of mixing renewals for wastewater treatment plants (WWTP) performing
				primary treatment shall comply with section 301(h) of the Federal Water
				Pollution Control Act of 1972 (
				33 U.S.C.
				1251 ). No renewal shall be allowed except
				upon application. Any renewal application shall be made at least one hundred
				and eighty days prior to the expiration of the zone of mixing.
(8) No zone of mixing established pursuant to
				this part shall be construed to prevent or limit the application of any
				emergency provisions and procedures provided by law.
(9) The establishment of any zone of mixing
				shall be subject to the concurrence of the U.S. Environmental Protection
				Agency.
(10) Each mixing zone may
				be subject to revocation, suspension, or modification if, after notice and
				opportunity for a hearing pursuant to chapter
				91, HRS and the rules of practice and
				procedures of the department, the director determines that the terms specified
				in section
				342D-6,
				HRS have been violated. In taking any action, the director may consider
				operating records, compliance investigations, or other information regarding
				discharge quality or impact on receiving waters. The action shall be effected
				by giving written notice to the permittee, which shall contain the reasons for
				the action.
(11) The director shall
				be notified within thirty days of the permanent discontinuance of a discharge.
				The zone of mixing shall terminate thirty days after such notification has been
				received.
(12) Upon expiration of
				the period stated in the designation, the zone of mixing shall automatically
				terminate and no rights shall become vested in the designee.