5.02.030 Antidegradation Policy And Implementation Procedures, Mixing Zones, And Allowance For Compliance Schedules

(a) Antidegradation Policy:

This antidegradation standard shall be applicable to any action or activity by any source, point or nonpoint, of pollutants that is anticipated to result in an increased loading of pollutants to Tribal surface waters. Pursuant to this standard:

(1) Existing instream water uses, as defined herein, and the level of water quality necessary to protect existing uses shall be maintained and protected. Where designated uses of the water body are impaired, there shall be no lowering of the water quality with respect to the pollutant or pollutants which are causing the impairment;

(2) Where, for any parameter, the quality of the waters exceed levels necessary to support the protection and propagation of fish, shellfish, and wildlife and recreation in and on the waters, that water shall be considered high quality for that parameter consistent with the definition of high quality water found at subsection of this antidegradation standard and that quality shall be maintained and protected unless the Tribe finds, after full satisfaction of Tribe's intergovernmental coordination and public participation provisions of the Tribe's continuing planning process, that allowing lower water quality is necessary to accommodate important economic or social development in the area in which the waters are located. In allowing such degradation, the Tribe shall assure water quality adequate to fully protect existing uses. Further, the Tribe shall assure that there shall be achieved the highest statutory and regulatory requirements for all new and existing point sources and all cost-effective and reasonable best management practices for nonpoint source control. The Tribe shall utilize the Antidegradation Implementation Procedures set forth below in determining if any lowering of water quality will be allowed;

(A) The Tribe identifies waters for the protections described in paragraph (a)(2) of this section on a parameter-by-parameter basis.

(B) Before allowing any lowering of high water quality, pursuant to paragraph (a)(2) of this section, the Tribe shall find, after an analysis of alternatives, that such a lowering is necessary to accommodate important economic or social development in the area in which the waters are located. The analysis of alternatives shall evaluate a range of practicable alternatives that would prevent or lessen the degradation associated with the proposed activity. When the analysis of alternatives identifies one or more practicable alternatives, the Tribe shall only find that a lowering is necessary if one such alternative is selected for implementation.

(3) Where high quality waters constitute an outstanding national or tribal resource, such as waters of national and State parks and wildlife refuges and waters of exceptional recreational, religious or ecological significance, that water quality shall be maintained and protected; and

(4) In those cases where the potential lowering of water quality is associated with a thermal discharge, the decision to allow such degradation shall be consistent with Section 316 of the Clean Water Act (CWA).

(A) As described in Section B. below, the Tribe has developed methods for implementing the antidegradation policy that are, at a minimum, consistent with the Tribe's policy and with paragraph (a) of this section. The Tribe shall provide an opportunity for public involvement during the development and any subsequent revisions of the implementation methods, and shall make the methods available to the public.

(b) Antidegradation Implementation Procedures:

(1) Definitions.

(A) Control Document. Any authorization issued by a State, Tribal or Federal agency to any source of pollutants to waters under its jurisdiction that specifies conditions under which the source is allowed to operate.

(B) High quality waters. High quality waters are water bodies in which, on a parameter by parameter basis, the quality of the waters exceeds levels necessary to support propagation of fish, shellfish, and wildlife and recreation in and on the water.

(C) Outstanding Resource Waters. Those waters designated as such by the Tribe. The Waters that may be considered for designation as Outstanding Resource Waters include, but are not limited to, water bodies that are recognized as:

(i) Important because of protection through official action, such as Tribal, Federal or State law, Presidential or secretarial action, international treaty, or interstate compact;

(ii) Having exceptional recreational significance;

(iii) Having exceptional ecological significance;

(iv) Having other special environmental, recreational, religious or ecological attributes; or waters whose designation as Outstanding Resource Waters is reasonably necessary for the protection of other waters so designated.

(D) Significant Lowering of Water Quality. A significant lowering of water quality occurs when there is a new or increased loading of any Persistent Bioaccumulative Toxics (PBT) from any regulated existing or new facility, either point source or nonpoint source for which there is a control document or reviewable action, as a result of any activity including, but not limited to:

(i) Construction of a new regulated facility or modification of an existing regulated facility such that a new or modified control document is required;

(ii) Modification of an existing regulated facility operating under a current control document such that the production capacity of the facility is increased;

(iii) Addition of a new source of untreated or pretreated effluent containing or expected to contain any PBT to an existing wastewater treatment works, whether public or private;

(iv) A request for an increased limit in an applicable control document;

(v) Other deliberate activities that, based on the information available, could be reasonably expected to result in an increased loading of any pollutant to Tribal surface waters.

(2) Notwithstanding the above, changes in loadings of any Persistent Bioaccumulative Toxic within the existing capacity and processes, and that are covered by the existing applicable control document, are not subject to an antidegradation review. These changes include, but are not limited to:

(A) Normal operational variability;

(B) Changes in intake water pollutants;

(D) Increasing the rate of production.

(3) Also, excluded from an antidegradation review are new effluent limits based on improved monitoring data or new water quality criteria or values that are not a result of changes in pollutant loading.

(4) For all waters, the Environment Division shall ensure that the level of water quality necessary to protect existing uses is maintained. In order to achieve this requirement, water quality standards use designations must include all existing uses. Controls shall be established as necessary on point and nonpoint sources of pollutants to ensure that the criteria applicable to the designated use are achieved in the water and that any designated use of a downstream water is protected. Where water quality does not support the designated uses of a water body or ambient pollutant concentrations exceed water quality criteria applicable to that water body, the Environment Division shall not allow a lowering of water quality for the pollutant or pollutants preventing the attainment of such uses or exceeding such criteria.

(5) For Outstanding Resource Waters:

(A) The Environment Division shall ensure, through the application of appropriate controls on pollutant sources, that water quality is maintained and protected.

(B) Exception. A short-term, temporary (i.e., weeks or months) lowering of water quality may be permitted by the Environment Division (or US EPA where SRMT is the permittee).

(C) For Natural State, high quality waters, the Environment Division shall ensure that no action resulting in a lowering of water quality occurs unless an antidegradation demonstration has been completed pursuant to Section C and the information thus provided is determined by the Environment Division pursuant to Section B of this Antidegradation Standard to adequately support the lowering of water quality.

(6) The Environment Division or EPA shall establish conditions in the control document applicable to the regulated facility that prohibit the regulated facility from undertaking any deliberate action, such that there would be an increase in the rate of mass loading of any pollutant, unless an antidegradation demonstration is provided to the Environment Division and approved pursuant to Section D prior to commencement of the action. Imposition of limits due to improved monitoring data or new water quality criteria or values, or changes in loadings of any pollutant within the existing capacity and processes, and that are covered by the existing applicable control document, are not subject to an antidegradation review.

(7) For PBTs known or believed to be present in a discharge, from a point or nonpoint source, a monitoring requirement shall be included in the control document. The control document shall also include a provision requiring the source to notify the Environment Division of any increased loadings. Upon notification, the Environment Division shall require actions as necessary to reduce or eliminate the increased loading.

(8) Fact Sheets prepared for public review and comment shall reflect any conditions developed under this Antidegradation Standard and included in a permit.

(9) Exemptions. Except as the Environment Division may determine on a case- by-case basis that the application of these procedures is required to adequately protect water quality, or as the affected water body is an Outstanding Resource Water as defined in Section B of this Antidegradation Standard, the procedures in this part do not apply to:

(A) Short-term, temporary (i.e., weeks or months) lowering of water quality;

(B) Bypasses that are not prohibited at 40 CFR 122.41(m); and

(C) Response actions pursuant to the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), as amended, or similar Federal, State or Tribal authorities, undertaken to alleviate a release into the environment of hazardous substances or pollutants which may pose an imminent and substantial danger to public health or welfare.

Any entity seeking to lower water quality in a High Quality Water must first, as required by Section B of this Antidegradation Standard, submit an antidegradation demonstration for consideration by the Environment Division. The antidegradation demonstration shall include the following:

(1) Pollution Prevention Alternatives Analysis. Identify any cost-effective pollution prevention alternatives and techniques that are available to the entity, that would eliminate or significantly reduce the extent to which the increased loading results in a lowering of water quality.

(2) Alternative or Enhanced Treatment Analysis. Identify alternative or enhanced treatment techniques that are available to the entity that would eliminate the lowering of water quality and their costs relative to the cost of treatment necessary to achieve applicable effluent limitations.

(3) Important Social or Economic Development Analysis. Identify the social or economic development and the benefits to the area in which the waters are located that will be foregone if the lowering of water quality is not allowed.

(4) Special Provision for Remedial Actions. Entities proposing remedial actions pursuant to the CERCLA, as amended, corrective actions pursuant to the Resource Conservation and Recovery Act, as amended, or similar actions pursuant to other Federal, State or Tribal environmental statutes may submit information to the Environment Division that demonstrates that the action utilizes the most cost effective pollution prevention and treatment techniques available, and minimizes the necessary lowering of water quality, in lieu of the information required by Section B of this Antidegradation Standard.

(d) Antidegradation Decision:

Once the Environment Division determines that the information provided by the entity proposing to increase loadings is administratively complete, the Environment Division shall use that information to determine whether or not the lowering of water quality is necessary, and, if it is necessary, whether or not the lowering of water quality will support important social and economic development in the area. If the proposed lowering of water quality is either not necessary, or will not support important social and economic development, the Environment Division shall deny the request to lower water quality. If the lowering of water quality is necessary, and will support important social and economic development, the Environment Division may allow all or part of the proposed lowering to occur as necessary to accommodate important social and economic development.

(e) Mixing Zones:

(1) Where effluent is discharged into surface waters, a continuous zone shall be maintained in which the water is of adequate quality to allow the migration of aquatic life with no significant effect on their population. The cross-sectional zone area of wastewater mixing zones shall generally be less than 1/4 of the cross-sectional area or flow volume of the receiving river, stream or lake. Unmixed zones containing permitted effluent shall not be at locations of recreational or ceremonial use. (See Section V, below.) Water quality standards shall be maintained throughout Zones of Passage. Zones of passage in intermittent streams may be designated on a site specific basis. The water quality in a Zone of Passage shall not fall below standards for the designated water body(ies) within which the zone is contained.

(2) Mixing zones will not be granted for discharges to outstanding resource water, wetlands, or ephemeral or intermittent streams.

(3) Mixing zones will not be granted for Persistent Bioaccumulative Toxics (PBT) consistent with the requirements of 40 CFR Part 132. See appendix 1. Waste Load Applications (WLAs) in the absence of TMDLs, and WLAs for the purposes of determining the need for water quality based effluent limits (WQBELs) for new discharges of PBTs shall be set equal to the most stringent applicable criteria or values for the PBTs in question.

(4) Mixing zones shall not be used for, or considered as, a substitute for waste treatment.

(f) Allowance for Compliance Schedules

NPDES permits, and other orders and directives of the Division issued under Tribal Council, for existing discharges or activities may include a schedule for achieving compliance with water quality criteria contained herein, consistent with the requirements of 40 CFR Parts 131.15 and 132. These compliance schedules shall be developed to ensure compliance with the water quality standards set forth in the shortest practicable time period, not to exceed five years. Decisions regarding whether to issue compliance schedules will be done on a case-by-case basis by the Tribal Council and approved by the Division, or the EPA where appropriate. These schedules will not be issued for new discharges or activities.

(g) Water Quality Standards Variances

It is the SRMT's policy that a water quality standards variance is only appropriate when a designated use is not attainable in the short-term but might be attainable in the long-term. The SRMT may consider a temporary modification to a designated use and associated water quality criteria that would otherwise apply.

(1) Applicability: A variance from any WQS that is the basis of a water quality-based effluent limitation included in a Permit is based on the following:

(A) A variance from WQS applies only to the permittee requesting the WQS variance, the water body/waterbody segment(s) specified in the WQS variance and only to the pollutant or pollutants specified in the WQS variance.

(B) A WQS variance does not affect, or require the SRMT to modify, in its standards, the underlying designated use and criterion address by the WQS variance, unless the SRMT adopts and EPA approves a revision to the underlying designated use and criterion consistent with §131.10 and §131.11. All other applicable standards not specifically addressed by the WQS variance remain applicable.

(C) A variance does not affect, or require SRMT to modify, the corresponding water quality standard for the waterbody as a whole.

(D) A WQS variance, once adopted by the SRMT and approved by EPA, shall be the applicable standard for purposes of the CWA under 40 CFR 131.21(d)-(e), for the following limited purposes. An approved WQS variance applies for the purposes of developing permit limits and requirements under 301(b)(1)(C), where appropriate, consistent with paragraph (a)(1) of this section. The SRMT and other certifying entities may also use an approved WQS variance when issuing certifications under section 401 of the CWA.

(E) A variance from a water quality standard shall not be granted that would likely jeopardize the continued existence of any endangered or threatened species listed under Section 4 of the Federal Endangered Species Act (ESA) Act or result in the destruction or adverse modification of such species' critical habitat.

(F) A variance from WQS shall not be granted if standards will be attained by implementing effluent limits required under sections 301(b) and 306 of the CWA and by the permittee implementing cost-effective and reasonable best management practices for nonpoint source control.

(2) The maximum timeframe: A variance from the WQS shall not exceed five (5) years or the term of the permit, whichever is less. The SRMT will review, and modify as necessary, variances from WQS as part of each water quality standards review pursuant to section 303(c) of the CWA.

(3) Conditions to grant: A variance from the WQS may be granted if, and only if:

(A) The permittee demonstrates to the SRMT that attaining the WQS is not feasible because:

(i) Naturally occurring pollutant concentrations prevent the attainment of the WQS;

(ii) Natural, ephemeral, intermittent or low flow conditions or water levels prevent the attainment of the WQS, unless these conditions may be compensated for by the discharge of sufficient volume of effluent to enable WQS to be met without violating the SRMT's water conservation requirements;

(iii) Human-caused conditions or sources of pollution prevent the attainment of the WQS and cannot be remedied, or would cause more environmental damage to correct than to leave in place;

(iv) Dams, diversions or other types of hydrologic modifications preclude the attainment of the WQS, and it is not feasible to restore the waterbody to its original condition or to operate such modification in a way that would result in the attainment of the WQS;

(v) Physical conditions related to the natural features of the waterbody, such as the lack of a proper substrate cover, flow, depth, pools, riffles, and the like, unrelated to chemical water quality, preclude attainment of WQS; or

(vi) Controls more stringent than those required by sections 301(b) and 306 of the CWA would result in substantial and widespread economic and social impact.

(B) The permittee shall also:

(i) Show that the WQS variance requested conforms to the requirements of the antidegradation procedures in Section III.A; and

(ii) Characterize the extent of any increased risk to human health and the environment associated with granting the WQS variance compared with compliance with WQS absent the variance, such that the SRMT is able to conclude that any such increased risk is consistent with the protection of the public health, safety and welfare.

(4) Requirements for Submission of Application to the SRMT:

(A) An application for a WQS variance must include:

(i) Identification of the pollutant(s) or water quality parameter(s), and the water body/waterbody segment(s) to which the WQS variance applies. Discharger(s)-specific WQS variances must also identify the permittee(s) subject to the WQS variance.

(ii) The requirements that apply throughout the term of the WQS variance. The requirements shall represent the highest attainable condition of the water body or waterbody segment applicable throughout the term of the WQS variance based on the documentation required in (d)(2) of this section. The requirements shall not result in any lowering of the currently attained ambient water quality, unless a WQS variance is necessary for restoration activities, consistent with paragraph (d)(2)(A)(i)(b) of this section. DPNR must specify the highest attainable condition of the water body or waterbody segment as a quantifiable expression that is one of the following:

(I) For discharger(s)-specific WQS variances:

(a) The highest attainable interim criterion, or

(b) The interim effluent condition that reflects the greatest pollutant reduction achievable, or

(c) If no additional feasible pollutant control technology can be identified, the interim criterion or interim effluent condition that reflects the greatest pollutant reduction achievable with the pollutant control technologies installed at the time the Territory adopts the WQS variance, and the adoption and implementation of a Pollutant Minimization Program.

(II) For WQS variances applicable to a water body or waterbody segment:

(a) The highest attainable interim use and interim criterion, or

(b) If no additional feasible pollutant control technology can be identified, the interim use and interim criterion that reflects the greatest pollutant reduction achievable with the pollutant control technologies installed at the time the Territory adopts the WQS variance, and the adoption and implementation of a Pollutant Minimization Program.

(iii) A statement providing that the requirements of the WQS variance are either the highest attainable condition identified at the time of the adoption of the WQS variance.

(iv) The term of the WQS variance, expressed as an interval of time from the date of the SRMT approval or a specific date. The term of the WQS variance must only be as long as necessary to achieve the highest attainable condition and consistent with the demonstration provided in paragraph (d)(2) of this section. The SRMT may adopt a subsequent WQS variance consistent with this section.

(B) The supporting documentation must include:

(i) Documentation demonstrating the need for a WQS variance.

(I) For a WQS variance to a use specified in section 101(a)(2) of the CWA or a sub-category of such a use, the SRMT must demonstrate that attaining the designated use and criterion is not feasible throughout the term of the WQS variance because:

(a) All relevant information demonstrating that attaining the WQS is not feasible based on one or more of the conditions in §186-14 (c)(1) herein; or

(b) Actions necessary to facilitate lake, wetland, or stream restoration through dam removal or other significant reconfiguration activities preclude attainment of the designated use and criterion while the actions are being implemented.

(II) For a WQS variance to a non-101(a)(2) use, the SRMT must submit documentation justifying how its consideration of the use and value of the water for those uses listed in § 131.10(a) appropriately supports the WQS variance and term. A demonstration consistent with (d)(2)(A)(i) of this section may be used to satisfy this requirement.

(ii) Documentation demonstrating that the term of the WQS variance is only as long as necessary to achieve the highest attainable condition. Such documentation must justify the term of the WQS variance by describing the pollutant control activities to achieve the highest attainable condition, including those activities identified through a Pollutant Minimization Program, which serve as milestones for the WQS variance.

(iii) In addition to (A) and (B) of this section, for a WQS variance that applies to a water body or waterbody segment:

(I) Identification and documentation of any cost-effective and reasonable best management practices for nonpoint source controls related to the pollutant(s) or water quality parameter(s) and water body or waterbody segment(s) specified in the WQS variance that could be implemented to make progress towards attaining the underlying designated use and criterion. DPNR must provide public notice and comment for any such documentation.

(II) Any subsequent WQS variance for a water body or waterbody segment must include documentation of whether and to what extent best management practices for nonpoint source controls were implemented to address the pollutant(s) or water quality parameter(s) subject to the WQS variance and the water quality progress achieved.

(iv) All relevant information demonstrating compliance with the conditions in (c)(2) herein.

(5) Implementing WQS variances in NPDES permits: A WQS variance serves as the applicable water quality standard for implementing permitting requirements pursuant to 40 CFR § 122.44(d) for the term of the WQS variance. Any limitations and requirements necessary to implement the WQS variance shall be included as enforceable conditions of the permit for the permittee(s) subject to the WQS variance.

(6) Public notice of preliminary decision: Upon receipt of a complete application for a variance from the WQS, and upon making a preliminary decision regarding the WQS variance, the SRMT shall public notice the request and preliminary decision for public comment. This public notice will be satisfied by including the supporting information for the variance from the WQS and the preliminary decision in the public notice of a draft TPDES permit.

(7) Final decision: The SRMT will issue a final decision on a WQS variance request within 90 days of the expiration of the public comment period required in accordance with the permit. If the SRMT approves all or part of the variance from the WQS, the decision shall include all permit conditions needed to implement those parts of the WQS variance as approved. Such permit conditions shall, at a minimum, require:

(A) Compliance with an initial effluent limitation which, at the time the variance from the WQS is granted, represents the level currently achievable by the permittee, and which is no less stringent than that achieved under the previous permit;

(B) Achieving reasonable progress toward attaining the water quality standards for the waterbody as a whole through appropriate conditions;

(C) When the duration of a variance from the WQS is shorter than the duration of a permit, compliance with an effluent limitation sufficient to meet the underlying water quality standard, upon the expiration of said WQS variance; and

(D) A provision that allows the SRMT to reopen and modify or revoke any condition granted in a WQS variance due to the permittee not providing relevant information that reasonable would affect the decision process.

(8) Incorporating the WQS variance: The SRMT will establish and incorporate into the permittee's permit all conditions needed to implement the variance from the WQS as determined in (g) herein.

(9) Renewal of WQS variance: A WQS variance may be renewed, subject to the requirements of (a) through (h) herein. As part of any renewal application, the permittee shall again demonstrate that attaining the WQS is not feasible based on the requirements of (c). The permittee's application shall also contain information concerning its compliance with the conditions incorporated into its permit as part of the original variance from the WQS pursuant to (g) through (h) herein. Renewal of a WQS variance may be denied if the permittee did not comply with the conditions of the original WQS variance.

(10) EPA Approval: The SRMT shall submit all variances from the WQS and supporting information to EPA Region 2 for approval. The submittal shall include:

(A) Relevant permittee applications pursuant to (d),

(B) Public comments and records of any public hearings pursuant to (f),

(D) Permits issued pursuant to (h) of this procedure.