La. Admin. Code tit. 33 § IX-1109
Current through Register Vol. 50, No. 6, June 20, 2024
Water quality standards policies concerned with the protection and enhancement of water quality in the state are discussed in this Section. Policy statements on antidegradation, water use, water body exception classification, compliance schedules, variances, short-term activity authorization, errors, severability, revisions to standards, and sample collection and analytical procedures are described.
A. Antidegradation Policy 1. State policy is that all waters of the state, including interstate, intrastate, and coastal waters, and any portions thereof, whose existing quality exceeds the specifications of the approved water quality standards or otherwise supports an unusual abundance and diversity of fish and wildlife resources, such as waters of national and state parks and refuges, will be maintained at their existing high quality. After completion of appropriate analysis and after completion of the public participation processes outlined in the water quality management plan and the continuing planning process, the state may choose to allow lower water quality in waters that exceed the standards to accommodate justifiable economic and/or social development in the areas in which the waters are located, but not to the extent of violating the established water quality standards. No such changes, however, will be allowed if they impair the existing water uses. No lowering of water quality will be allowed in waters where designated water uses are not currently being attained.2. Where the water quality exceeds levels necessary to support the protection and propagation of fish, shellfish, and wildlife and recreation in and on the water, that water quality shall be maintained and protected unless the state finds, after full satisfaction of the intergovernmental coordination and public participation provisions of the states 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. The state shall assure water quality adequate to fully protect existing uses with such degradation or lower water quality. The state shall assure the highest statutory and regulatory requirements shall be achieved for all new and existing point sources and all cost-effective and reasonable best management practices for nonpoint source control. a. Waters may be identified for the protections described in Paragraph 2 of this Subsection on a parameter-by-parameter basis or on a water body-by-water body basis. Where the state identifies waters for antidegradation protection, the state shall provide an opportunity for public involvement in any decisions about whether the protections described in Paragraph 2 of this Subsection will be given to a water body, and the factors considered when making those decisions. A water body shall not be excluded from the protections described in Paragraph 2 of this Subsection solely because water quality does not exceed levels necessary to support all of the uses specified in section 101(a)(2) of the Clean Water Act.b. Before allowing any lowering of high water quality, according to Paragraph 2 of this Subsection, the state 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 state shall only find that a lowering is necessary if one such alternative is selected for implementation.3. Waste discharges shall comply with applicable state and federal laws for the attainment of water quality goals. Any new, existing, or expanded point source or nonpoint source discharging into state waters, including any land clearing which is the subject of a federal permit application, shall be required to provide the necessary level of waste treatment to protect state waters as determined by the administrative authority. Further, the highest statutory and regulatory requirements shall be achieved for all existing point sources and best management practices (BMPs) for nonpoint sources. Additionally, no degradation shall be allowed in high-quality waters designated as outstanding natural resource waters, as defined in LAC 33:IX.1111.A. Waters included in the Louisiana Natural and Scenic Rivers System, under the administration of the Louisiana Department of Wildlife and Fisheries, will be considered by the department for designation as outstanding natural resource waters. Those water bodies presently designated as outstanding natural resource waters are listed in LAC 33:IX.1123. The administrative authority shall not approve any wastewater discharge or certify any activity for federal permit that would impair water quality or use of state waters, including waters in the Natural and Scenic Rivers System that are waters of the state.4. The antidegradation policy and implementation method shall be consistent with section 316 of the Clean Water Act where a potential water quality impairment is associated with a thermal discharge.5. An implementation plan for this antidegradation policy is provided in LAC 33:IX.1119. The states methods for implementing the antidegradation policy shall be, at a minimum, consistent with the states policy and with the federal regulations at 40 CFR 131.12(a). The state shall provide an opportunity for public involvement during the development and any subsequent revisions of the implementation methods.B. Water Use 1. It is the policy of the state of Louisiana that all state waters should be protected for recreational uses and for the preservation and propagation of desirable species of aquatic biota and indigenous species of wildlife. Use and value of water for public water supplies, agriculture, industry, and other purposes, as well as navigation, shall also be considered in setting standards. The most stringent criteria specified for each parameter shall be applicable where waters are classified for multiple uses.2. In applying this policy, the terms recreational uses and desirable species of aquatic biota will be given common sense applications. Recreational uses will be classified as either primary contact or secondary contact. Desirable species of aquatic biota refers to a diverse and naturally occurring range of aquatic biota and not to species that exist in the area in question in disproportionate numbers as a result of wastewater discharges. Desirable species of fish, shellfish and other invertebrates, wildlife, and other aquatic biota will be specified as fresh warmwater or marine water species. All future designations of water uses and their associated criteria must, at a minimum, adhere to these classifications, except as provided in LAC 33:IX.1109.B.3 and C.3. Designated uses which are not existing uses may be removed from water bodies if it is demonstrated through a use attainability analysis and the administrative authority determines that the designated use is not feasible because of one or more of the following reasons: a. naturally occurring pollutant concentrations prevent the attainment of the use;b. natural, ephemeral, intermittent, or low flow conditions or water levels prevent the attainment of the use, unless these conditions may be compensated for by the discharge of sufficient volume of effluent discharges without violating water conservation requirements to enable uses to be met;c. human caused conditions or sources of pollution prevent the attainment of the use and cannot be remedied or would cause more environmental damage to correct than to leave in place;d. dams, diversions, or other types of hydrologic modifications preclude the attainment of the use, and it is not feasible to restore the water body to its original condition or to operate such modification in a way that would result in the attainment of the use;e. physical conditions related to the natural features of the water body, unrelated to water quality, such as the lack of a proper substrate, cover, flow, depth, pools, riffles, and the like, preclude attainment of aquatic life protection uses; orf. controls more stringent than those required by Sections 301(b) of the Clean Water Act would result in substantial and widespread economic and social impact.4. The department shall ensure that the water quality standards provide for the attainment and maintenance of the water quality standards of the downstream waters when designating water body uses and the appropriate criteria for those uses.5. A subcategory of a use may be adopted and the appropriate criteria set to reflect the varying needs of such a subcategory of a use.C. Water Body Exception Classification. Some water bodies may qualify for a water body exception classification. This classification will be made on a case-by-case basis. Whenever data indicate that a water body exception classification is warranted, the department will recommend the exception to the administrative authority for approval. In all cases where exceptions are proposed, the concurrence of EPA must be obtained and the opportunity for public participation must be provided during the exceptions review process. The general criteria of these standards shall apply to all water bodies classified as a water body exception except where a particular water body is specifically exempted. A use attainability analysis shall be conducted to justify a water body exception classification if an accompanying downgrade of a 101(a)(2) use and application of less stringent criteria is being proposed. Exceptions are allowed for the following three classifications of water bodies.
1. Intermittent Streams a. Only those streams which have seasonal no-flow conditions or water levels that preclude primary contact recreation and the propagation of desirable species of fish and wildlife will be considered for classification as intermittent. The general criteria of these standards shall apply to all water bodies classified as intermittent streams except where a particular stream is specifically exempted.b. An intermittent stream is defined as a water body in which natural conditions of flow, width, and depth preclude primary contact recreational water uses and the propagation of a balanced population of aquatic biota. Because of one or more of these conditions, such streams provide only an ephemeral, aquatic habitat which is not conducive to the establishment of a balanced population of aquatic biota or to recreational activities. This definition does not include those water bodies that contain enduring pools which support recreational uses and desirable species of aquatic biota, or water bodies which are subject to tidal effects and may contain standing water with no flow during periods of slack tide.c. For a stream to be considered for classification as intermittent, the stream must lack sufficient drainage area to maintain a perennial flow. The no-flow condition must be natural and not a result of human activities. The no-flow condition of intermittent streams is generally characterized by dry stream reaches and shallow isolated pools during summer dry weather conditions; however, the water body may exhibit flow or contain deeper pools for short periods after rainfall.d. No stream may be classified as intermittent without the approval of both the administrative authority and the EPA. A use attainability analysis may be conducted to gather additional water body characterization data necessary to justify an intermittent stream classification. If such a classification is justified, seasonal uses and criteria may be established.e. A wastewater discharge may be proposed into an approved, designated intermittent stream only if the discharge will not by itself or in conjunction with other discharges cause impairment of the applicable designated uses nor cause exceedance of any applicable general and site-specific criteria in the receiving water body, as determined in the exception approval process, nor cause exceedance of any applicable general and site-specific criteria in LAC 33:IX.1113 and 1123 in any water body which receives water from the intermittent stream.2. Man-Made Water Bodies a. A man-made water body is defined as a ditch, canal or channelized stream created specifically and used primarily for drainage or conveyance of water. Some natural streams have been channelized to such an extent that conveyance of water is the principal use, usually precluding reasonable primary contact recreation and balanced fish and wildlife propagation. Such natural, channelized streams may be considered for classification as man-made water bodies. The general criteria provided in LAC 33:IX.1113.B shall apply to all water bodies classified as man-made water bodies except where a particular water body is specifically exempted.b. For a water body to be considered for this excepted water use classification, its principal use must be drainage or conveyance of water. In addition, the water body must not be used as a source of public water supply. Some man-made water bodies that produce new aquatic habitat and subsequently are populated by desirable aquatic species and/or that have some water contact recreational use may, on a case-by-case basis, be considered under this policy. However, the physical characteristics of man-made water bodies that may fall under this exception are not conducive to the establishment of a balanced population of aquatic biota or to the full support of recreational activities.c. No stream may be classified as man-made without the approval of both the administrative authority and the EPA. A use attainability analysis may be conducted to gather data to justify a man-made water body classification. If the man-made classification is justified, revised water quality criteria and uses, if applicable, will be established.d. A wastewater discharge may be proposed into an approved, designated man-made water body only if the discharge will not by itself or in conjunction with other discharges cause impairment of the applicable designated uses nor cause exceedance of any applicable general and site-specific criteria in the receiving water body, as determined in the exception approval process, nor cause exceedance of any applicable general and site-specific criteria in LAC 33:IX.1113 and 1123 in any water body which receives water from the man-made water body.3. Naturally Dystrophic Waters a. Naturally dystrophic waters include waters that receive large amounts of natural organic material largely of terrestrial plant origin, are commonly stained by the decomposition of such organic material, and are low in dissolved oxygen because of natural conditions. Only those water bodies primarily affected by nonanthropogenic sources of oxygen-demanding substances or naturally occurring cycles of oxygen depletion will be considered for classification as naturally dystrophic waters. These water bodies typically include or are surrounded by wetlands (e.g., bottomland hardwood forests, freshwater swamps and marshes, or intermediate, brackish, or saline marshes) and have sluggish, low-gradient flows most of the year. Naturally dystrophic water bodies, though seasonally deficient in dissolved oxygen, may fully support fish and wildlife propagation and other water uses. Low dissolved oxygen concentrations (less than 5 mg/L) may occur seasonally during the warmer months of the year in naturally dystrophic water bodies.b. No water body may be classified as naturally dystrophic without the approval of both the administrative authority and the EPA. A use attainability analysis may be conducted to gather data to document the characteristics of a naturally dystrophic water body. A use attainability analysis must be conducted to support the modification of dissolved oxygen criteria and/or the seasonality of dissolved oxygen criteria in naturally dystrophic waters. Applicable general and numeric criteria not specifically exempt shall remain applicable to waters classified as naturally dystrophic.c. A wastewater discharge to an approved naturally dystrophic water body may be proposed only if the discharge will not by itself or in conjunction with other discharges, cause impairment of the applicable designated uses, nor cause exceedance of any applicable general and site-specific criteria in the receiving water body, as determined in the exception approval process, nor cause exceedance of any applicable general and site-specific criteria in LAC 33:IX.1113 and 1123 in any water body that receives water from the naturally dystrophic water body.d. A wastewater discharge may be proposed for an approved, designated naturally dystrophic water body in a wetland only if the discharge will not by itself, or in conjunction with other discharges, cause inundation of the receiving area such that regeneration of characteristic vegetative species would be significantly reduced, will not significantly modify species composition of the receiving area, and will not increase biological succession of the receiving area above naturally occurring levels. Natural background conditions and proposed significant changes will be determined through use attainability analyses prior to the addition of any discharge.D. Compliance Schedules in LPDES Permits. Upon permit issuance, modification, or renewal, compliance schedules may be incorporated into a permit to allow a permittee adequate time to make treatment facility modifications necessary to comply with water quality-based permit limitations determined to be necessary to implement new or revised water quality standards. Compliance shall be achieved at the earliest practicable time. The department will establish interim conditions which may consist of, but are not limited to, compliance schedules, monitoring requirements, temporary limits, and milestone dates so as to measure progress toward final project completion (e.g., design completion, construction start, construction completion, date of compliance). E. Water Quality Standards (WQS) Variances 1. The state may adopt a WQS variance, as defined in Section 1105 of this Chapter. The WQS variance is subject to the provisions of this Subsection and public participation requirements at 40 CFR 131.14 and is a water quality standard subject to EPA review and approval or disapproval under section 303(c) of the Clean Water Act. a. Applicability i. A WQS variance may be adopted for a permittee(s) or water body/water body segment(s), but only applies to the permittee(s) or water body/water body segment(s) specified in the WQS variance.ii. When adopting a WQS variance the underlying designated use and criterion addressed by the WQS variance shall be retained, unless a revision to the underlying designated use and criterion is adopted by the department and approved by EPA consistent with federal regulations. All other applicable standards not specifically addressed by the WQS variance remain applicable.iii. Once the WQS variance is adopted by the state and approved by EPA, it shall be the applicable standard for purposes of the Clean Water Act under 40 CFR 131.21(d)-(e), for the following limited purposes of developing LPDES permit limits and requirements under federal regulations, where appropriate, consistent with Clause E.1.a.i of this Subsection.iv. A WQS variance will not be adopted if the designated use and criterion addressed by the WQS variance can be achieved by implementing technology-based effluent limits required under sections 301(b) of the Clean Water Act.b. Requirements for Submission to EPA. The following information shall be included in the WQS variance submitted to EPA when granting a variance request for a permittee(s), or water body/water body segment(s). i. Identify the pollutant(s) or water quality parameter(s) and the water body/water body segment(s) to which the WQS variance applies. A discharger(s)-specific WQS variance shall also identify the permittee(s) subject to the WQS variance.ii. Provide the requirements that apply throughout the term of the WQS variance. The requirements shall represent the highest attainable condition of the water body or water body segment applicable throughout the term of the WQS variance based on the required supporting documentation. 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 LAC 33:IX.1109.E.1.c.i.(a).(ii). The state shall specify the highest attainable condition of the water body or water body segment as a quantifiable expression that is one of the following: (a). for a discharger(s)-specific WQS variance: (i). the highest attainable interim criterion; (ii). the interim effluent condition that reflects the greatest pollutant reduction achievable; or(iii). 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 state adopts the WQS variance, and the adoption and implementation of a pollutant minimization program, as defined in Section 1105 of this Chapter:(b). for a WQS variance applicable to a water body or water body segment: (i). the highest attainable interim use and interim criterion; or(ii).if no additional feasible pollutant control technology can be identified, the interim use and interim criterion that reflect the greatest pollutant reduction achievable with the pollutant control technologies installed at the time the state adopts the WQS variance, and the adoption and implementation of a pollutant minimization program.iii. Provide a statement that the requirements of the WQS variance are either the highest attainable condition identified at the time of the adoption of the WQS variance, or the highest attainable condition later identified during any reevaluation consistent with Clause E.1.b.v of this Subsection, whichever is more stringent.iv. State the term of the WQS variance, expressed as an interval of time from the date of EPA approval or a specific date. The term of the WQS variance shall only be as long as necessary to achieve the highest attainable condition and consistent with the demonstration provided in Subparagraph E.1.c of this Subsection. The state may adopt a subsequent WQS variance consistent with this Subsection.v. For a WQS variance with a term greater than five years, specify a frequency to reevaluate the highest attainable condition using all existing and readily available information and stipulate a provision how the state intends to obtain public input on the reevaluation. Such reevaluations shall occur no less frequently than every five years after EPA approval of the WQS variance and the results of such reevaluation shall be submitted to EPA within 30 days of completion of the reevaluation.vi. A provision of the WQS variance shall stipulate the WQS variance will no longer be the applicable water quality standard for purposes of the Clean Water Act if the state does not conduct a reevaluation consistent with the frequency specified in the WQS variance or the results are not submitted to EPA as required by Clause E.1.b.v of this Subsection until the state conducts the reevaluation and submits the results to EPA.c. The supporting documentation submitted to EPA shall include the following. i. Documentation that shall demonstrate the need for a WQS variance. (a).For a WQS variance to a Clean Water Act section 101(a)(2) use or a subcategory of such a use, the state shall demonstrate that attaining the designated use and criterion is not feasible throughout the term of the WQS variance because: (i).one of the factors listed in Clause B.3 of this Section is met; or(ii).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.(b).For a WQS variance to a non-Clean Water Act section 101(a)(2) use, the state shall submit documentation justifying how its consideration of the use and value of the water for those uses listed in 40 CFR 131.10(a) appropriately supports the WQS variance and term. A demonstration consistent with Subclause E.1.c.i.(a) of this Subsection may be used to satisfy this requirement.ii. Documentation that shall demonstrate that the term of the WQS variance is only as long as necessary to achieve the highest attainable condition. Such documentation shall 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 Clause E.1.c.i and ii of this Subsection, for a WQS variance that applies to a water body or water body segment: (a).Identify and document 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 water body segment(s) specified in the WQS variance that could be implemented to make progress towards attaining the underlying designated use and criterion (The state shall provide public notice and comment for any such documentation).(b).Any subsequent WQS variance for a water body or water body segment shall 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. d. Implementation of a WQS variance in an LPDES permit. A WQS variance serves as the applicable water quality standard for implementation of LPDES permitting requirements pursuant to LAC 33:IX.2707.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 LPDES permit for the permittee(s) subject to the WQS variance. F. Short-Term Activity Authorization. The administrative authority may exempt from water quality standards certain short-term activities that the state determines are necessary to accommodate activities, emergencies, or to protect the public health and welfare. Such activities shall not cause long-term or permanent impact on designated water uses. These activities may include, but are not limited to, mosquito abatement projects, algae and weed control projects, and fish eradication projects. No short-term activity authorization shall supersede any applicable state or federal law or regulation including permitting process or the terms or conditions of any permit.G. Errors. Errors resulting from inadequate or erroneous data and human or clerical errors will be subject to correction by the state, and the discovery of such errors does not render the remaining or unaffected standards invalid.H. Severability. If any provisions of these standards or the application of any provision of these standards to any person or circumstance is held invalid, the application of such provision to other persons or circumstances and the remainder of the standards shall not be affected thereby.I. Water Quality Standards Revision Process 1. It is the position of the state of Louisiana that the standards contained herein are those that are reasonable on the basis of the actual or potential quality of the state's waters, present and future water uses, and the best practicable wastewater treatment under any conditions. However, standards are not fixed for all time, but are subject to future revision. The nature of future revisions of these standards will be strongly influenced by many factors. Among these are the following. a. As a downstream or bordering state in all cases involving interstate streams, Louisiana's standards will be affected by the quality of water received from its upstream and neighboring states.b. Because it is the state farthest downstream, Louisiana's water quality will be affected by mean low flows when interstate rivers and tributaries become subject to flow regulation and diversion projects.c. Changes in technology or natural conditions, or the availability of new data, may require a revision of numeric criteria at any time. Such revisions, however, will be accomplished only after proper consideration of designated water uses. Any proposed revision will be consistent with state and federal regulations.d. Advances in scientific knowledge concerning the toxicity, cancer potency, metabolism, or exposure pathways of toxic pollutants that affect the assumptions on which existing criteria are based may necessitate a revision of numeric criteria at any time. Such revisions, however, will be accomplished only after proper consideration of designated water uses. Any proposed revision will be consistent with state and federal regulations.2. The state shall hold public hearings at least once every three years to review applicable water quality standards and, as appropriate, modify and adopt standards. The revised standards will be reviewed in accordance with the state Administrative Procedure Act (R.S. 49:950 et seq.) and appropriate EPA procedures.J. Sample Collection and Analytical Procedures. Procedures for collecting and analyzing samples to be used to determine whether the standards have been attained shall be subject to the following requirements as well as those specified in the departments Quality Assurance (QA) Plan for water monitoring and analysis. 1. Samples will be obtained at a depth or depths representative of the average water quality at the sampling station in question.2. Samples will be collected from sampling locations as necessary to assess attainment of standards.3. Collection and preservation of samples will be in accordance with accepted practices as specified in the department's QA Plan.4. Numeric values of the various parameters will typically be determined by analytical procedures as specified in the QA Plan.K. Wetlands 1. Wetlands, as defined in LAC 33:IX.1105, are a valuable resource to the state of Louisiana. Because of the states natural low elevations, extensive riverine and riparian environments, and the presence of the Mississippi River delta, Louisiana has a large and diverse amount of wetland habitat. Specific values of Louisiana wetlands include commercial, recreational, and cultural uses. In addition, Louisiana wetlands provide important biological and physiochemical functions that include, but are not limited to, buffering against hurricanes and storms, holding excess floodwaters during high rainfall or high tides, recharging groundwater aquifers used for drinking water and irrigation, and improving water quality by filtering pollutants and taking up nutrients.2. There are two basic types of Louisiana wetlands: forested wetlands and non-forested, or marsh, wetlands. Forested wetlands include bottomland hardwood swamps, continuously flooded cypress-tupelo swamps, seasonally flooded cypress-tupelo swamps, and oligotrophic seasonally flooded pine forests. Non-forested or marsh wetlands include floating freshwater emergent wetlands, attached freshwater emergent wetlands, brackish marshes, and salt (saline) marshes. Each of these wetland types are defined in LAC 33:IX.1105.3. Wetlands approved by the administrative authority for wastewater assimilation projects pursuant to the Water Quality Management Plan, Volume 3, Section 10, Permitting Guidance Document for Implementing Louisiana Surface Water Quality Standards, are assigned the following designated uses: secondary contact recreation and fish and wildlife propagation.4. Applicable Criteria. Wetlands provide several values and functions that necessitate water quality criteria protective primarily of vegetative productivity. Additionally, wetlands can periodically become anoxic or anaerobic, or lack water altogether. Therefore, the following criteria are applicable to wetlands approved by the administrative authority for wastewater assimilation projects pursuant to the Water Quality Management Plan, Volume 3, Section 10, Permitting Guidance Document for Implementing Louisiana Surface Water Quality Standards. a. A numeric dissolved oxygen criterion is not necessary to protect the beneficial use of fish and wildlife propagation.b. The general criteria found in LAC 33:IX.1113.B, except for LAC 33:IX.1113.B.3 and 9, apply.c. Numeric criteria found in LAC 33:IX.1113.C.4, 5.b, and 6 apply.d. The biological criteria found in LAC 33:IX.1113.B.12.b apply.e. Additional or site-specific criteria may be necessary to protect other existing or beneficial uses identified by the administrative authority. The following site-specific criteria have been approved by the administrative authority for wastewater assimilation projects. i. Luling Wetland, South Slough Wetland, Chinchuba Swamp Wetland, East Tchefuncte Marsh Wetland, Cypress Island Coulee Wetland, and Cote Gelee Wetland Designated Naturally Dystrophic Waters Segment. The following criteria are applicable: no more than 20 percent reduction in the total above-ground wetland productivity, as measured by tree, shrub, and/or marsh grass productivity.ii. Poydras-Verret Marsh Wetland Designated Naturally Dystrophic Waters Segment. The following criteria are applicable: (a). no more than 50 percent reduction in the wetlands faunal assemblage total abundance, total abundance of dominant species, or the species richness of fish and macroinvertebrates, minimum of five replicate samples per site; p = 0.05; and/or(b). no more than 20 percent reduction in the total above-ground wetland productivity as measured by tree, shrub, and/or marsh grass productivity.iii. Breaux Bridge Swamp and Thibodaux Swamp - Designated Naturally Dystrophic Waters Segment. The following criteria are applicable:(a). no more than 20 percent decrease in naturally occurring litter fall or stem growth;(b). no significant decrease in the dominance index or stem density of bald cypress; and/or(c). no significant decrease in faunal species diversity and no more than a 20 percent decrease in biomass.iv. Bayou Ramos Swamp Wetland - Designated Naturally Dystrophic Waters Segment. The following criteria are applicable:(a). no more than 20 percent decrease in naturally occurring litter fall or stem growth;(b). no significant decrease in the dominance index or stem density of bald cypress; and/or(c). no significant decrease in faunal species diversity and no more than a 20 percent decrease in abundance.5. A wastewater discharge may be proposed for a wetland of any defined type only if the discharge will not cause impairment of the wetland or exceedance of applicable general or site-specific criteria. 6. Discharges to wetlands approved by the administrative authority for wastewater assimilation projects will only be permitted following procedures pursuant to the Water Quality Management Plan, Volume 3, Section 10, Permitting Guidance Document for Implementing Louisiana Surface Water Quality Standards.La. Admin. Code tit. 33, § IX-1109
Promulgated by the Department of Environmental Quality, Office of Water Resources, LR 10:745 (October 1984), amended LR 15:738 (September 1989), LR 17:264 (March 1991), LR 17:966 (October 1991), LR 20:883 (August 1994), amended by the Office of Environmental Assessment, Environmental Planning Division, LR 26:2546 (November 2000), LR 29:557 (April 2003), amended by the Office of the Secretary, Legal Affairs Division, LR 33:457 (March 2007), LR 33:828 (May 2007), amended by the Office of the Secretary, Legal Division, LR 402243 (11/1/2014), Amended by the Office of the Secretary, Legal Affairs and Criminal Investigations Division, LR 461546 (11/1/2020), Amended by LR 47876 (7/1/2021), Amended by the Office of the Secretary, Legal Affairs Division, LR 491552 (9/1/2023).AUTHORITY NOTE: Promulgated in accordance with R.S. 30:2074(B)(1).