Oklahoma Administrative Code › Title 252 - Department of Environmental Quality › Chapter 690 - Water Quality Standards Implementation › Subchapter 7 - Water Quality Standards Implementation Plan, Oklahoma Department of Environmental Quality › Section 252:690-7-2 - WQSIP Elements by Jurisdictional Area

Current through Vol. 41, No. 20, July 1, 2024
(a)
General.
The eight required WQSIP elements are presented by
				jurisdictional area, and in some cases individual program areas within the
				scope of the jurisdictional area. DEQ's WQSIP will evolve to adapt to future
				changes in the WQS and WQS implementation criteria.
(b)
DEQ Jurisdictional Areas.
The jurisdictional areas of the Department of Environmental Quality are listed
				in 27A O.S. §1-3-101(B), 27A O.S. § 2-6-103(B)(2), and 82 O.S. §
				1085.30.
(c)
Water Quality
				Planning.
(1)
Compliance with
				antidegradation requirements and protection of beneficial uses.
The
				antidegradation policy in the WQS prohibits an increase in loading that would
				impair or further impair an existing use. In addition, the policy prohibits
				degradation of outstanding resource waters and high-quality waters, even if
				existing and designated uses would still be attained. Current CPP procedures
				regarding the 303(d) list, TMDL's, and loading allocations for both point and
				nonpoint sources of pollution are consistent with these provisions. DEQ may
				also adopt variances and site-specific criteria as set forth in 27A O.S. §
				2-6-103(B).
(2)
Application
				of USAP.
Although evaluation of beneficial use support is not a water
				quality planning responsibility, its TMDL function is closely related and is
				utilized on a continuing basis to identify water bodies where USAP might be
				utilized to reevaluate a waterbody's beneficial uses. USAP, WQS, and EPA
				guidance will be considered to set appropriate target end points in the
				development of TMDLs.
(3)
Description of programs affecting water quality.
The CPP document,
				developed pursuant to requirements of Section 303(e) of the CWA, provides the
				basis and guidance for all water quality planning activities at DEQ. Water
				quality planning staff are responsible for several water quality planning
				program elements:
(A) Developing procedures
				for planning and implementing water quality management programs in the
				CPP.
(B) Preparing recommendations
				for the listing and delisting of waterbodies in the 303(d) List.
(C) Establishing TMDLs for 303(d)-listed
				waterbodies and coordinating TMDLs with other state environmental
				agencies.
(4)
Technical information and procedures for implementation.
Technical
				information and procedures used in water quality planning activities are
				included in the CPP. Because it is such a significant element in water quality
				planning, the TMDL development process is described in detail. Proposed
				adoption of a TMDL is considered a major change to the state's Water Quality
				Management Plan. Public participation in TMDL development and adoption shall be
				conducted in accordance with state requirements and the procedures outlined in
				the CPP. The TMDL loading allocation process culminates in the allocation of
				pollutant loads among various point sources, nonpoint sources, natural
				background sources and a margin of safety (MOS), according to the following
				equation: TMDL= WLA + LA + MOS. TMDL is loading capacity, the maximum amount of
				pollutant loading a water body can receive without violating WQS. WLA is
				wasteload allocation, the portion of a receiving water's loading capacity that
				is allocated to existing and future point sources. LA is load allocation, the
				portion of a receiving water's loading capacity that is allocated to existing
				and future nonpoint sources and to natural background sources. MOS is margin of
				safety, the prescribed mechanism to account for the uncertainty in determining
				the amount of pollutant load and its effect on water quality. MOS is typically
				considered implicitly with conservative assumptions within calculations or
				models, explicitly during allocation of loads, or both. The major components of
				TMDL development are assessment of existing conditions, determination of
				maximum allowable loading, and allocation of loadings.
(A)
Assessment of Existing
				Conditions
(i)
Water
				Quality.
The first step in assessing the current conditions is to gather
				available data and information on the water body. At a minimum, the water
				quality data (if available) that was used for listing the water body (re:
				303(d) List) should be reviewed. The sufficiency and adequacy of existing data
				is evaluated and described. DEQ will consider data to be sufficient and
				adequate when the data accurately characterizes the conditions of the water
				body, watershed, pollutant, and pollutant sources throughout typical geographic
				and temporal conditions with reasonable certainty. Some TMDL projects will
				require additional watershed information relating to particular water quality
				conditions, as existing data alone may be insufficient to support the
				analytical needs of TMDL projects. Data on low-flow conditions, storm-flow
				conditions, and seasonal variations are gathered when appropriate to the
				situation. Data will be evaluated considering USAP, WQS, and EPA
				guidance.
(ii)
Pollutant
				Load.
Before pollutant loads are allocated among sources, the location
				and types of sources, and the current and projected pollutant load for each
				source are identified. Current loading and source contributions are established
				by measuring pollutant loads directly, calculating or estimating loads from
				water quality and flow data, estimating loads with mathematical models, or
				using a combination of these methods. Examples of data utilized for pollutant
				source analysis include: watershed and sub watershed boundaries; hydrologic
				interaction between surface water and groundwater; locations of stream
				segments; locations of pollutant sources; types of pollutant sources;
				anticipated growth of discharges; meteorological/rainfall data and runoff
				coefficients; land uses and land cover; and, soil types. An inventory is
				developed of all known factors in the watershed which influence water quality.
				These factors might include permitted industrial and municipal wastewater
				discharges, concentrated animal feeding operations (CAFOs), waste application
				sites, cropland, forestry operations, industrial stormwater runoff, urban
				runoff, construction activities, and other sources such as natural background.
				This information will be collected and maintained by sub-watershed where
				possible to enhance the identification of cause-and-effect relationships. The
				watershed inventory is compiled from land use data, special investigations, DEQ
				complaint investigations, DEQ permit databases, surface water monitoring data,
				input from other agencies, and watershed stakeholder input through an outreach
				process.
(B)
Maximum Allowable Loading.
A water body's loading capacity is an
				estimate of the maximum amount of pollutant loading the water body, considering
				critical conditions (i.e. flow, temperature, etc.), can receive over time
				without exceeding WQS. Hydrological, biological, chemical, and pollutant fate
				and transport data are required to calculate a water body's loading capacity.
				The maximum loading capacities of a waterbody are determined in most cases
				using a water quality model or models adapted specifically for the waterbody in
				question. The model used is selected on a case-by-case basis and is based on
				available resources, the identified pollutant source(s) and the availability of
				water quality data.
(C)
				A
llocation of Loadings.
Future growth, spatial and temporal
				variations in flows and loadings, antibacksliding, antidegradation and
				pollutant sources and source categories must be considered and incorporated
				when developing a loading, unless it is demonstrated that one or more of these
				factors is not relevant to the particular load allocation.
(D)
Pollution Allocation
				Strategies.
There are three common methods for allocating loads; equal
				percent removal, equal effluent concentrations, and a hybrid method. Other
				methods are considered if necessary.
(i)
Equal Percent Removal.
Equal percent removal exists in two forms.
				In one, the overall removal efficiencies of the sources are set so that they
				are all equal. In the other, the incremental removal efficiencies beyond the
				current discharge are equal.
(ii)
Equal Effluent Concentration.
This method is self-evident. It is
				similar to equal percent removal if influent concentrations at all sources are
				approximately the same.
(iii)
Hybrid Method.
With this method, the criteria for waste reduction
				may not be the same from one source to the next. One source may be allowed to
				operate unchanged while another may be required to provide the entire load
				reduction. More generally, however, a proportionality rule may be assigned that
				requires the percent removal to be proportional to the input source loading or
				flow rate.
(iv)
Other
				Methods.
Any other method contained in EPA guidance. DEQ shall approve
				the use of the method on a case-by-case basis.
(E)
Pollutant Trading.
Where
				appropriate and technically feasible, tradeoffs among wasteload allocations are
				considered. Technological feasibility, economic issues, and regulatory
				authority are evaluated when trading allocations. Pollutant trades are
				acceptable so long as WQS (including antidegradation regulations and policies)
				and minimum applicable technology-based controls are met.
(F)
Margin of Safety.
The margin
				of safety (MOS) is the prescribed mechanism to account for the uncertainty
				associated with TMDL projects. Guidelines for appropriate margins of safety are
				included in the CPP. The MOS can be included in more than one of the TMDL
				analytical steps. To represent the MOS, conservative assumptions should be used
				in completing one or more of the following steps:
(i) derivation of numeric water quality
				targets;
(ii) determination of
				pollutant sources;
(iii)
				representation of pollutant fate and transport relationships; and
(iv) determination of the degree of pollutant
				reduction achievable through management measures and control actions
(5)
Integration of
				WQSIP into water quality management activities.
DEQ administrative rules
				and WQD policies are currently in place which integrate the requirements of the
				WQSIP into water quality planning. Should WQSIP revisions be necessary in
				future years, rule changes and policy changes will be made to address and
				incorporate such requirements.
(6)
Compliance with mandated statewide water quality requirements.
TMDL activities comply with the procedures established in the CPP. Coordination
				of TMDL activities among state agencies is the primary responsibility of the
				TMDL Work Group, which is chaired by DEQ and includes the state environmental
				agencies with water quality responsibilities.
(7)
Public and interagency
				participation.
DEQ regularly collects and will collect a summary of
				comments and will provide responses thereto relating to promulgation of DEQ's
				WQSIP.
(8)
Evaluation of
				effectiveness of agency activities.
The 303(d) listing/delisting
				process, which in turn utilizes USAP, will be used to evaluate the
				effectiveness of all DEQ programs related to surface water quality.