4.1 Federal Regulations

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1 SECTION 4 Future Effluent Limitation Scenarios This technical memorandum describes effluent limitations and future effluent limitation scenarios for wastewater facilities for the City of McCall, Idaho (the City). It partially fulfills Task Order 20, Subtask 2.0, as part of the Master Agreement dated June 2005 for Professional Services between CH2M HILL, Inc. (the Engineer) and the City in support of the City s Wastewater Management System. This background documentation will be used to develop a wastewater facilities plan for the City. Wastewater facilities planning and the related wastewater treatment requirements for various discharge scenarios must comply with the applicable federal and state regulations. This technical memorandum consists of the following sections: 1. Federal Regulations 2. State Regulations 3. Future Effluent Limitation Scenarios 4.1 Federal Regulations The federal Clean Water Act (CWA) requires that states and tribes restore and maintain the chemical, physical, and biological integrity of the nation s waters. States and tribes must adopt water quality standards necessary to protect fish, shellfish, and wildlife while providing for recreation in and on the waters whenever possible (IDEQ, 2006a) Total Maximum Daily Load Background Section 303(d) of the CWA establishes requirements for states and tribes to identify and prioritize water bodies that are water quality limited (that is, water bodies that do not meet water quality standards). States and tribes must periodically publish a priority list of impaired waters, currently every 2 years. For waters identified on this list, states and tribes must develop water quality improvement plans known as total maximum daily loads (TMDLs) that establish allowable pollutant loads set at levels to achieve water quality standards Overview of the TMDL Process 3 Water quality standards have been established by the Idaho legislature and approved by the U.S. Environmental Protection Agency (EPA). These standards are designed to protect, restore, and preserve water quality in areas designated for specific uses such as cold, cool, or warm water fisheries; agricultural water supply; recreation; wildlife habitat; and aesthetics. Uses have been designated for most, but not all, water bodies within Idaho. 3 Most of the material in sections , , and is from IDEQ s Surface Water: Water Quality Improvement Plans (TMDLs) web site (IDEQ, 2006a). BOI DOC/KM REVISED DRAFT 4-1

2 Currently, IDEQ is required to conduct a comprehensive analysis of Idaho s water bodies every 2 years to determine if they meet water quality standards. This analysis is published and submitted to the EPA in a document called an Integrated Report. Idaho must develop a water quality plan (the TMDL) for those water bodies not found to be meeting water quality standards. Over 900 river and stream segments and some lakes in Idaho were identified as impaired in the 2002 Integrated Report (IDEQ, 2004), and TMDLs must be developed for each of these. Idaho and the EPA have a legal, court-ordered responsibility to ensure that these impaired waters are dealt with in a timely manner. In Idaho, TMDLs are assessed on a subbasin level, which means water bodies and pollutants within a hydrologic subbasin are generally addressed in a single document. A subbasin is based on a cataloging unit of the U.S. Geological Survey (USGS) (a subbasin is the same as a USGS fourth field hydrologic unit, or HUC). There are 84 subbasins (HUCs) in Idaho. As of March 2004, 35 of Idaho s 84 HUCs had approved TMDLs TMDL Basics Simply put, a TMDL is a pollutant budget. A TMDL is a calculation of the maximum amount of a pollutant that a water body can receive from human-caused sources and still meet water quality standards. This budget is expressed in terms of loads: the amounts of pollutants added to a water body during a given time or per a volume of water. For example, a load allocation to a water body might be 10 pounds of phosphorus per day from a given source. A TMDL budget takes into account loads from point, nonpoint, and natural background sources. The load assigned to point sources is called a wasteload allocation (WLA); the load assigned to nonpoint sources is called a load allocation (LA). The TMDL budget is balanced at the point where water quality standards are just being met and is allocated among all the various sources. Some of the TMDL budget is set aside as a margin of safety. The TMDL budget must take into account the seasonal or cyclic nature of pollutant loads and the receiving water s capacity, so a temporary exceedance does not occur. The TMDL budget can be summarized as the following: The load capacity (LC) of a water body = a margin of safety (MOS) + natural background (NB) + allocations to pollutant sources (WLA and LA) = TMDL. The equation is written in this order because it represents the logical order in which a TMDL is developed. First, the load capacity is determined. The load capacity is the quantity of a pollutant a water body can receive over a given period without causing violations of state water quality standards. Then the load capacity is broken down into its components. That is, a margin of safety is determined and subtracted; then natural background, if relevant, is quantified and subtracted; and the remainder is allocated among pollutant sources. When the breakdown and allocation are completed, the result is a TMDL, which must equal the load capacity. In addition to being a pollutant load, TMDL also refers to the written, quantitative assessment of water quality problems and contributing pollutant sources. IDEQ has the authority and the responsibility to ensure that TMDLs are completed and submitted for 4-2 REVISED DRAFT BOI DOC/KM

3 EPA approval. The EPA has the responsibility to approve or disapprove all TMDLs. If the EPA formally disapproves a state TMDL, the state is obligated under the CWA to issue a new TMDL within 30 days. Subbasin Assessment A subbasin assessment is the first step in developing a TMDL or recommending removing a water body from the list of impaired waters in the Integrated Report. Conducting the assessment entails analyzing and integrating multiple types of water body data, such as biological, physical, chemical, and landscape data. A subbasin assessment describes the affected area, the water quality concerns, the status of beneficial uses of individual water bodies, the nature and location of pollution sources, and past and ongoing pollution control activities. Its main purpose is to determine the causes and extent of the impairment when water bodies are not attaining water quality standards. While a subbasin assessment is not required by the CWA, IDEQ completes the assessment to ensure impairment listings are up-to-date and accurate. The subbasin assessment is usually part of the TMDL document, but may be prepared separately. Pollutants A pollutant is a substance, such as bacteria or sediment, that is identifiable and in some way quantifiable. Some unnatural conditions that impair water quality, such as flow alteration, human-caused lack of flow, and habitat alteration, are considered pollution, but are not caused by quantifiable pollutants. Temperature, while not a substance, is considered a pollutant, as changes in water temperature are quantifiable. A TMDL is only required to address pollution that is caused by pollutants. Therefore, if a water body is impaired because of pollution, but not a pollutant, that water body will not receive a TMDL for that pollution. If a water body is impaired by pollution and a pollutant (for example, habitat alteration and bacteria), it will still receive a TMDL for the pollutant (in this case, bacteria). Types of Pollutants In general, watersheds are subject to two broad categories of pollution sources: point and nonpoint. Point source pollution is typically associated with industrial and municipal waste treatment facility discharges, and confined animal feeding operations. The effects can be directly traced to a particular source or facility (a point ). Point source pollution can often be measured at an outfall or pipe. Nonpoint source pollution, on the other hand, is more difficult to identify. It includes, among other things, the cumulative effects of fertilizers and pesticides that farmers and homeowners may use; and various land use practices including urban development, agriculture, and forestry. Due to its rural nature, most pollution in Idaho is nonpoint source pollution. The specific pollutants of concern vary from watershed to watershed. In much of rural Idaho, water quality concerns center around excess sedimentation, elevated stream temperatures, and nutrient overloading. In developed areas, concerns often focus on bacteria, oil and grease, and dissolved oxygen. In industrial or mining areas, heavy metals are often at the top of the list. BOI DOC/KM REVISED DRAFT 4-3

4 DEQ collects data on individual water bodies in Idaho and solicits data from outside sources such as other government agencies. These data are compared to Idaho s water quality standards to determine if a particular water body is meeting standards and supporting beneficial uses. The findings are documented in the Integrated Report. While IDEQ frequently is able to determine what pollutants (if any) are impairing water quality from these data, this determination is not required at this stage. A water body may be listed in IDEQ s Integrated Report as not supporting its beneficial uses or meeting standards, with the pollutant identified as unknown. In the subbasin assessment phase of writing a TMDL, more data about the water body are collected. At this stage, IDEQ determines what pollutants are causing the impairments and the sources of those pollutants. Because a TMDL is a total maximum daily load, pollutants are generally measured and allocated as loads (a concentration [mass/volume] or the amount of a pollutant measured over time [mass/time]). Once a water body is listed as impaired in the Integrated Report, it is placed on the TMDL Schedule. Each TMDL must be submitted to the EPA by December 31 the year it is due. It takes approximately 2 years to write a TMDL. However, this process can take longer if the subbasin is highly complex. When a TMDL is completed, the next task is to implement its recommendations and meet its goals. An implementation plan is written, guided by an approved TMDL. It provides details of the actions needed to achieve load reductions and a schedule of those actions. It also specifies the monitoring needed to document action and progress toward meeting water quality standards Cascade Reservoir Watershed Management Plan 4 Cascade Reservoir is located in the Payette River Basin of southwestern Idaho. Two rivers (North Fork Payette River [NFPR] and Gold Fork River) and four creeks (Mud Creek, Lake Fork Creek, Boulder Creek, and Willow Creek) all discharge into the northern end of the reservoir. The watershed includes two major drainages: the Big Payette Lake drainage area and the Cascade Reservoir drainage area (the area included in the Cascade Reservoir Watershed Management Plan). Cascade Reservoir is a shallow water body, and, as such, it is highly susceptible to eutrophication due to nutrient loading and elevated summer water temperatures. Eutrophication was especially apparent in 1993 and 1994 when dense mats of blue-green algae were present in the reservoir. Twenty-three cattle died in 1993 after ingesting toxins produced by the algae and a substantial fish kill occurred in The discharge of nutrients to Cascade Reservoir and its tributaries, including the NFPR, has resulted in excess algae and aquatic plant growth in violation of Idaho Administrative Procedures Act (IDAPA) , Water Quality Standards and Wastewater Treatment Requirements in Cascade Reservoir. The particular nutrient of concern is phosphorus. As a result of the impairment of water quality in Cascade Reservoir, the reservoir was identified by IDEQ as a high priority water quality limited segment pursuant to 4 Most of the material in this section is from IDEQ s Surface Water: Cascade Reservoir Watershed Management Plan, Phases I and II (Payette River Basin) web site (IDEQ, 2006b). 4-4 REVISED DRAFT BOI DOC/KM

5 Section 303(d) of the CWA. In October of 1995, IDEQ finalized the Cascade Reservoir Watershed Management Plan, which constitutes the functional equivalent of a TMDL required by Section 303(d) of the CWA for all water quality limited segments. This TMDL was approved by the EPA in May The TMDL projects that a 37 percent overall reduction in phosphorus load to Cascade Reservoir must be implemented to achieve state Water Quality Standards. In order to meet this goal, the TMDL provides for a zero discharge of phosphorus, or complete removal of the treated wastewater from the McCall wastewater treatment facility to the NFPR. The plan that was developed for achieving water quality improvements in Cascade Reservoir included three phases and an implementation plan as noted below: Phase I. Initial nutrient reduction goal and implementation strategy (approved by EPA in May 1996). Phase II. Further evaluation of phosphorus reduction goals and alternatives (approved by EPA in April 1999). Implementation Plan. A subwatershed-specific outline of projects that have been and will be initiated to effect required water quality improvements within Cascade Reservoir. Phase III. Plan evaluation and modification (underway) North Fork Payette River TMDL 5 The Payette River Watershed lies entirely in southwestern Idaho and comprises about 3,240 square miles. The drainage originates in the Sawtooth and Salmon River mountains and flows southwesterly until it empties into the Snake River near Payette, Idaho. The NFPR TMDL lies within parts of two hydrologic units and encompasses several geographically distinct subwatersheds. This TMDL addresses Section 303(d) listed tributaries to the NFPR above Payette Lake and to Payette Lake itself; the NFPR and tributaries from Cascade Dam to the confluence with the South Fork Payette River; and, finally, the Main Payette River up to and including Black Canyon Reservoir. The NFPR is listed for nutrients, sediment, and temperature. Beneficial uses are not impaired by nutrients, so nutrients are recommended for delisting. Temperatures exceed the temperature standard, but this is primarily due to warm water exiting Cascade Reservoir. Canopy cover meets target levels, so a TMDL was not developed for temperature. A TMDL for sediment was developed. Big Creek is listed as impaired by sediment, and data show that beneficial uses are impaired. Banks are stable in some sections but actively eroding in others. A TMDL was developed for sediment. In Round Valley Creek, beneficial uses are impaired due to excess sediment from instream channel erosion. A TMDL was developed. 5 Some of the material in this section is from IDEQ s Surface Water: North Fork Payette River Subbasin Assessment and Total Maximum Daily Loads web site (IDEQ, 2006c). BOI DOC/KM REVISED DRAFT 4-5

6 Temperature TMDLs were developed for Box Creek and Fall Creek in order to achieve salmonid spawning criteria. The streams support beneficial uses, but do not meet the salmonid spawning standard. Beneficial uses are not supported in the lower reach of Clear Creek due to excess sediment from upstream and in-stream channel erosion. In the upper reaches of Clear Creek, beneficial uses are fully supported, but are threatened due to excess sediment. A sediment TMDL was set for the upper watershed to improve habitat in the lower reaches. Browns Pond is listed for habitat alteration. However, habitat alteration is not considered a pollutant, and TMDLs are not required for pollution that is not caused by a pollutant. Therefore, a TMDL for Browns Pond was not developed. Soldier Creek is listed for sediment. IDEQ proposes de-listing Soldier Creek from the headwaters to the confluence with North Fork Soldier Creek, but leaving the lower section of Soldier Creek on the Section 303(d) list. IDEQ will use data gathered in 2005 to determine whether sediment is impairing beneficial uses in the lower section. Tripod Creek was preliminarily found to be unimpaired and a TMDL is not recommended at this time. Additional monitoring data will become available in 2005, which may result in further study of Tripod Creek and TMDL development. It is proposed that Brush Creek, Elip Creek, and Landing Creek be removed from the Section 303(d) list and that Black Canyon Reservoir be removed for nutrients, sediment, and oil and grease, but be added for habitat alteration. It is also proposed that Squaw Creek be added to the next Section 303(d) list for bacteria and nutrients. The TMDL was approved by EPA in August of Although the TMDL addresses the entire watershed in Hydrologic Unit Code, there are no water quality impairments listed for the NFPR between the outlet at Big Payette Lake and the upper end of Cascade Reservoir National Pollutant Discharge Elimination System (NPDES) The 1972 Amendments to the Federal Water Pollution Control Act (Public Law , known as the CWA), established the foundation for wastewater discharge control in this country. The CWA s primary objective is to restore and maintain the chemical, physical and biological integrity of the nation s waters. In 1972, the Clean Water Act established a control program for ensuring that communities have clean water by regulating the release of contaminants into our country s waterways. Permits that limit the amount of pollutants discharged are required of all municipal and industrial wastewater dischargers under the NPDES permit program. The CWA requires that municipal wastewater treatment plant discharges meet a minimum of secondary treatment (EPA Office of Wastewater Management [OWM], 2004). The City of McCall is required to operate under the terms of the Second Amended Consent Order (see Appendix B, Second Amended Consent Order), and this generally precludes a discharge to the NFPR. However, the treated wastewater from the City s wastewater treatment facility can be discharged to the NFPR at approximately River Mile 73 under the terms of an NPDES permit that became effective May 1, 2003, and shall expire at midnight, 4-6 REVISED DRAFT BOI DOC/KM

7 April 30, The NPDES permit, Response to Comments, and Fact Sheet are presented in Appendix C, NPDES Permit, Fact Sheet, and Response to Comments. Table summarizes the numerical permit limits. Authorization to discharge through the terms of the NPDES permit is restrictive. The permit requires that the City use the J-ditch system to convey all wastewater effluent from the City s wastewater treatment plant to the maximum extent practicable from June 1 though September 30. Emergency discharge limitations include: 1. Emergency discharge to the NFPR is limited to the period of December 1 through June 30 only when insufficient storage capacity exists or is anticipated to exist based upon flow projections. 2. Prior to discharge, McCall must notify and obtain approval of IDEQ. 3. McCall must maintain a 60:1 dilution of river flow to effluent flow. 4. The effluent limitations found in Table are applicable during an emergency discharge to the NFPR. TABLE Numerical NPDES Permit Effluent Limitations for Emergency Discharge to NFPR Parameter Average Monthly Limit Average Weekly Limit Daily Maximum Limit Biochemical Oxygen Demand (BOD 5 ) Total Suspended Solids (TSS) 20 mg/l 330 lbs/day 20 mg/l 330 lbs/day 30 mg/l 500 lbs/day 30 mg/l 500 lbs/day E. Coli Bacteria 126/100 ml 406/100 ml Total Residual Chlorine 0.5 mg/l ph Between 6.5 and 9.0 Standard Units NOTE: The average monthly effluent concentration for BOD 5 and TSS shall not exceed 15 percent of the respective monthly average influent concentrations. lbs/day = pounds per day mg/l = milligrams per liter ml = milliliters Wet Weather Discharges from Municipal Sewage Treatment Facilities 6 EPA is proposing for public comment a new policy for addressing very high or peak flow events at municipal wastewater treatment plants that are a result of significant storm events (EPA, 2005). The policy follows the joint recommendations of the Natural Resources Defense Council (NRDC) and the National Association of Clean Water Agencies (NACWA). The proposed policy describes limited circumstances when certain management techniques may be used by the operator of a municipal wastewater treatment facility to address very high flows that result from storm events. The policy also indicates how the management of peak flows must be documented in NPDES permits. 6 The material in this section is from EPA s Wet Weather Discharges web site (EPA, 2006). BOI DOC/KM REVISED DRAFT 4-7

8 Aging sewer line infrastructure in many communities allows rain and snowmelt to enter sanitary sewer systems. During significant storm events, these high volumes can overwhelm certain parts of the wastewater treatment process and may cause damage or failure of the system. Operators of wastewater treatment plants must manage these high flows to both ensure the continued operation of the treatment process and to prevent backups and overflows of raw wastewater in basements or on city streets. The proposed policy encourages municipalities to make investments in ongoing maintenance and capital improvements to improve their system s long-term performance. The policy outlines the limited circumstances when these management techniques can be used and how they must be documented in NPDES permits. The policy also stipulates that all NPDES permit limits must be met at all times. The policy encourages further public participation via the NPDES permit process, and provides for public notification when certain management techniques are used CFR Part 503 Biosolids Regulations The 40 Code of Federal Regulations (CFR) Part 503 regulations administered by EPA establish levels of biosolids quality with respect to metals concentrations and pathogen density. Currently the City of McCall s treatment facility does not generate biosolids that require disposal on a regular basis. However, the disposal of biosolids that accumulate in the aerated lagoons or ponds would be subject to the Part 503 regulations when removal and disposal are warranted Capacity, Management, Operation, and Maintenance (CMOM) EPA has written, but not yet implemented, Draft Capacity, Management, Operation, and Maintenance (CMOM) requirements. The CMOM requirements would especially affect the collection system. The CMOM regulations have six requirements: General Standards, Management Program, Overflow Response Plan, System Evaluation and Capacity Assurance Plan, Program Audits, and Communications. 1. General Standards. The General Standards require that the City ensure adequate capacity in the entire collection system for both base and peak flows, and take all feasible steps to mitigate sanitary sewer overflows (SSOs). If an overflow occurs, the City will be required to provide notification to parties who have potential for exposure. The General Standards also require the City to provide a written summary of the CMOM program, which is to be made available to the public. 2. Management Program. The Management Program must identify program goals, the organization and legal authority to implement CMOM, activities to carry out the program, development of design standards, and measurement of program effectiveness. Goals must be consistent with the General Standards. The Program must identify the administrative and maintenance positions responsible for implementation and procedures for reporting SSOs. The legal authority used to implement the program, such as sewer ordinances, must be identified. This authority must be used to control I/I; require that sewers, connections, and sewer rehabilitations be properly designed, tested, and constructed; address flows from satellite systems; and implement the prohibitions of the national pretreatment program. The plan must outline the activities and persons 4-8 REVISED DRAFT BOI DOC/KM

9 responsible for carrying out the program. Specific activities to be addressed include maintenance of the facility, maintenance of the collection system map, management of information that prioritizes CMOM activities and identifies trends in overflows, preventive maintenance, and an assessment of the current capacity of the collection system. Design standards for new and repair projects must be developed, and procedures for testing and inspection must be established. The program must be monitored and the program summary updated regularly. 3. Overflow Response Plan. An overflow response plan must be developed that ensures overflows are responded to and reported, the public is notified, and personnel are trained and respond to the overflow. 4. System Evaluation and Capacity Assurance Plan. If peak flows are contributing to SSOs, a System Evaluation and Capacity Assurance plan must be developed. The plan must evaluate and identify the areas of the collection system that experience SSOs, establish short-term and long-term goals to eliminate SSOs, and provide an implementation plan. The plan must be regularly updated. 5. Program Audits. As part of the NPDES permit application, an audit of SSOs must be submitted, including the number of overflows, deficiencies in the system, and steps taken to mitigate SSOs. 6. Communications. A communications plan must be established with interested parties on the development and implementation of the CMOM program. If these rules become effective, the CMOM Management Plan must be documented and the SSO audit must be submitted with the City s next NPDES application Environmental Regulations Key federal environmental regulations pertinent to the wastewater facilities plan include the following: Endangered Species Act (ESA). Projects that use federal funding or need to obtain federal permits must comply with the requirements of the ESA. The Act provides protection against take (defined as killing, harming, harassing, or altering habitat) of federally listed endangered species. Projects that involve potential taking of listed species must consult with the National Marine Fisheries Service and/or the U.S. Fish and Wildlife Service to determine appropriate measures to avoid, minimize, and/or mitigate impacts to these species. Magnuson-Stevens Fishery Conservation and Management Act. The National Marine Fisheries Service issued interim final regulations in December 1998 to implement the essential fish habitat (EFH) requirements of the 1996 Sustainable Fisheries Act, which had significantly amended the 1976 Magnuson-Stevens Fishery Conservation and Management Act. EFH is defined as waters and substrate necessary to fish for spawning, breeding, feeding, or growth to maturity. EFH must always include the critical habitat of endangered and threatened species. The Magnuson-Stevens Act required federal agencies to provide the National Marine Fisheries Service with a BOI DOC/KM REVISED DRAFT 4-9

10 written assessment of the effects on EFH of any federal action that may adversely affect EFH, except activities covered by a general concurrence. Clean Air Act. The Federal Clean Air Act of 1992 requires that all federally funded projects be in compliance with state and regional air quality plans. Local air pollution control agencies must be notified if a building is being renovated or demolished, and an asbestos survey is required. Wastewater treatment facilities are considered sources of air emissions under the Clean Air Act. National Environmental Policy Act. The National Environmental Policy Act (NEPA) applies primarily to projects receiving federal funding. Its primary goal is to help public officials make decisions based on an understanding of the environmental consequences and to take actions that protect, restore, and enhance the environment. To accomplish this, NEPA requires federal agencies to either prepare or have prepared written assessments or statements that describe the following: Affected environment and environmental consequences of a proposed project Reasonable or practicable alternatives to the proposed project Any mitigation measures necessary to avoid or minimize adverse environmental effects. In accordance with NEPA, the Council on Environmental Quality has issued regulations (40 CFR ) establishing a standard federal environmental review process. This process includes three levels of environmental review: Categorical exclusions Environmental assessments Environmental impact statements National Historic Preservation Act. This Act applies to all projects that receive funding from EPA, including pass-through funding to state water quality agencies. Designed to protect historic, cultural, and archaeological resources from damage or destruction, it requires that agencies undertaking projects consult with the State Historic Preservation Officer (SHPO) and local Native American tribes. In areas with a high likelihood of subsurface artifacts or other cultural resources, major capital projects involving earth disturbance typically must undertake a program of archaeological exploration to determine whether such resources are present. If resources are encountered during these investigations or during project construction, they must be evaluated, and a plan must be developed in conjunction with the SHPO and the affected tribe(s) for preservation, removal, or recording of the site and artifacts Public Participation Federal requirements for wastewater facilities plans call for public meetings prior to adoption of the plan. These meetings provide citizens with information about the contents of the wastewater facilities plan and an opportunity to ask questions and provide comments and statements regarding the plan REVISED DRAFT BOI DOC/KM

11 4.2 State Regulations Idaho Water Quality Standards Idaho Water Quality Standards and Wastewater Treatment Requirements (IDAPA ) protect the NFPR from Payette Lake to Cascade Reservoir for the following beneficial use classifications: cold water aquatic life (CWAL), salmonid spawning (SS), primary contact recreation (PCR), and domestic water supply (DWS) Cold Water Aquatic Life (CWAL) Waters designated for cold water aquatic life are not to vary from the following characteristics: ph values between 6.5 and 9.0 Total concentration of dissolved gas not to exceed 110 percent of saturation Dissolved oxygen concentrations exceeding 6.0 milligrams per liter (mg/l) at all times Water temperature of 22 degrees Celsius (ºC) or less with a maximum daily average of not greater than 19ºC. When natural background conditions exceed any applicable water quality criteria, the applicable water quality criteria do not apply; instead pollutant levels shall not exceed the natural background conditions. Maximum ammonia concentration depends on temperature and ph of the water body based on formulas for acute and chronic criteria Turbidity not to exceed background turbidity by more than 50 Nephelometric Turbidity Units (NTU) for any sample, or more than 25 NTU for more than 10 consecutive days Salmonid Spawning (SS) Waters designated for salmonid spawning are to exhibit the following characteristics during the spawning and incubation period: One day minimum intergravel dissolved oxygen of not less than 5 mg/l, and 7 day average of not less than 6 mg/l One day minimum water column dissolved oxygen of not less than 6 mg/l or 90 percent saturation, whichever is greater Water temperatures of 13ºC or less, with a maximum daily average not greater than 9ºC Primary Contact Recreation (PCR) Waters designated for primary contact recreation are not to contain E. coli bacteria in concentrations exceeding: 235 organisms per 100 milliliter (ml) at public swimming beaches 406 organisms per 100 ml, or a geometric mean of 126 organisms per 100 ml based on a minimum of five samples taken every 3 to 5 days over a 30-day period at other areas BOI DOC/KM REVISED DRAFT 4-11

12 Domestic Water Supply (DWS) Waters designated for domestic water supply are to exhibit the following characteristics: Radioactive materials are not to exceed specified concentrations stated in the IDEQ Rules Governing Public Drinking Water Systems found in IDAPA Toxic Substances The State has also adopted numeric criteria for 121 different toxic substances for waters designated for aquatic life, recreation, or domestic water supply use. These may be found at IDAPA Table summarizes several numeric criteria for toxic metals and cyanide that may be of interest to the City of McCall Reclamation and Reuse Requirements IDAPA provides the rules for the reclamation and reuse of municipal and industrial wastewater in the State of Idaho. These rules establish the procedures and requirements for the issuance and maintenance of pollution source permits for reclamation and reuse facilities, including permits for the treatment of municipal wastewaters for other reuse projects as defined in Subsection , Direct Use of Municipal Reclaimed Wastewater. Reclamation is the treatment of municipal wastewater that allows it to be reused for beneficial purposes. Reclamation also includes land treatment for wastewater that utilizes soil or crops for partial treatment. Reuse is the use of reclaimed wastewater for beneficial uses including, but not limited to, land treatment, irrigation, aquifer recharge, use in surface water features, toilet flushing in commercial buildings, dust control, and other uses. A reclamation or reuse facility then is a system designed and used for reclamation or reuse of municipal wastewater including wastewater treatment facilities, pumping and storage facilities, pipeline and distribution facilities, and the property to which the reclaimed wastewater is applied Permit Required Construction, modification, and operation of a reclamation or reuse facility require a valid permit issued by the IDEQ. A permit application shall be submitted to IDEQ at least 180 days prior to the day on which a new activity is to begin; or at least 180 days prior to the expiration of any permit issued pursuant to IDAPA Plan of Operation Required Any existing reclamation and reuse facility shall have a detailed plan of operation that describes in detail the operation, maintenance, and management of the wastewater treatment system. Any new proposed reclamation and reuse facility is required to have a detailed plan of operation at the 50 percent completion point of construction. In addition, 1 year after operation, the plan must be updated to reflect actual operating procedures REVISED DRAFT BOI DOC/KM

13 TABLE Numeric Criteria for Selected Toxic Substances for Waters Designated for Aquatic Life, Recreation, or Domestic Water Supply Use Parameter Aquatic Life Acute (μg/l) Aquatic Life Chronic (μg/l) Human Health Consumption of Water and Organisms (μg/l) Human Health for Consumption of Organisms Only (μg/l) Arsenic 340 a 150 a Cadmium 2 b 1.0 b Chromium III 570 b 74 b Copper 17 b 11 b Cyanide 22 d 5.2 d ,000 Lead 65 b 2.5 b Mercury c Nickel 470 b 52 b 610 4,600 Selenium 20 e 5 e Silver 3.4 b Zinc 120 b 120 b 7,400 26,000 (mg/kg of body weight) Methyl mercury 0.3 a Criteria for these metals expressed as function of the water effects ratio. b Aquatic life criteria for these metals expressed as a function of total hardness and the water effects ratio (values displayed are based on a total hardness of 100 mg/l and water effect ratio of 1.0). c No aquatic life criteria adopted for inorganic mercury. IDEQ believes application of human health criteria for methyl mercury will be protective of aquatic life in most situations. d Criteria are expressed as s weak acid dissociable cyanide. e Critierion expressed as total recoverable (unfiltered) concentrations. μg/l = micrograms per liter mg/kg = milligrams per kilogram Permit Conditions Conditions necessary for the protection of the environment and the public health may differ from facility to facility because of varying environmental conditions and wastewater compositions. IDEQ may establish on a case-by-case basis specific permit conditions that take into consideration the following characteristics: 1. Chemical, biological, and volumetric wastewater characteristics 2. Geologic and climatic nature of the facility 3. Size of the site and proximity to population centers, ground water and surface water 4. Legal considerations relative to land use and water rights 5. Techniques used in wastewater distribution 6. Ability of the soils and vegetative cover to treat the wastewater without undue hazard to the environment or to the public health 7. Need for monitoring and record keeping to ensure compliance BOI DOC/KM REVISED DRAFT 4-13

14 Rapid Infiltration Rapid infiltration is a wastewater land application treatment method by which wastewater is applied to land in an amount of 20 to 600 feet per year for percolation through the soil. Vegetation is not typically utilized with a rapid infiltration system. The following minimum treatment requirements are necessary prior to the land application of wastewater when followed by a rapid infiltration system: 1. The suspended solids content of wastewater shall not exceed a 30-day average concentration of 100 mg/l 2. The total nitrogen content of wastewater shall not exceed a 30-day average concentration of 20 mg/l Direct Use of Municipal Reclaimed Wastewater Treatment requirements applicable to the direct use of municipal reclaimed wastewater have been established by IDEQ. Treatment requirements are subdivided into five classes (A through E) as shown in Tables through TABLE Class A Effluent Type Treatment Requirements Disinfection Permitted Uses Access Restrictions Signing and Posting Buffer Distances Grazing Description Oxidized, coagulated, clarified, filtered, and disinfected. Total Nitrogen: shall not exceed 10 mg/l for ground water discharge; shall not exceed 30 mg/l for residential irrigation. Turbidity: daily arithmetic mean shall not exceed 2 NTU; shall not exceed 5 NTU at any time. BOD5: average shall not exceed 5 mg/l for ground water discharge; average shall not exceed 10 mg/l for residential irrigation. ph: from 6.0 to 9.0. Residual Chlorine: shall not be less than 1 mg/l free chlorine. Median number of total coliform organisms shall not exceed 2.2/100 ml. May be used for residential irrigation at individual homes, ground water recharge using surface spreading, seepage ponds, or other unlined surface water features. May be used for Class B, C, D, and E uses. Additional requirements for ground water recharge uses in IDAPA Irrigated during periods of non-use. Extensive requirements for identification of pipes, valves, valve boxes, storage, and pumping facilities and respective warning labels and warning signs. Not allowed to be applied to surface waters in circumstances where an NPDES permit is required. Grazing allowed only with approved grazing management plan REVISED DRAFT BOI DOC/KM

15 TABLE Class B Effluent Type Treatment Requirements Disinfection Permitted Uses Access Restrictions Signing and Posting Buffer Distances Grazing Description Oxidized, coagulated, clarified, filtered and disinfected. Turbidity: daily arithmetic mean shall not exceed 2 NTU; shall not exceed 5 NTU at any time. Residual Chlorine: shall not be less than 1 mg/l free chlorine. Median number of total coliform organisms shall not exceed 2.2/100 ml. May contact any edible portion of raw food crops, or is used to irrigate golf courses, parks, playgrounds, schoolyards, or Class C, D, and E uses. Irrigated during periods of non-use by the public. Site specific See Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (IDEQ, 2006d) Site specific See Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (IDEQ, 2006d). No effluent is allowed to be applied to surface waters in circumstances where an NPDES permit is required. Grazing allowed only with approved grazing management plan. TABLE Class C Effluent Type Treatment Requirements Disinfection Permitted Uses Access Restrictions Signing and Posting Buffer Distances Grazing Oxidized and disinfected. Description Median number of total coliform organisms shall not exceed 23/100 ml. May only contact the inedible portion of raw food crops, or is used to irrigate orchards and vineyards during the fruiting season, if no fruit harvested for raw use comes in contact with the irrigation water or ground, or will only contact the inedible portion of raw food crops, or is used to irrigate cemeteries, roadside vegetation, or Class D or E uses. Irrigated during periods of non-use by the public. Site specific See Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (IDEQ, 2006d). Site specific See Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (IDEQ, 2006d). No effluent is allowed to be applied to surface waters in circumstances where an NPDES permit is required. Grazing allowed only with approved grazing management plan. BOI DOC/KM REVISED DRAFT 4-15

16 TABLE Class D Effluent Type Description Treatment Requirements Disinfection Permitted Uses Access Restrictions Signing and Posting Buffer Distances Grazing Oxidized and disinfected. Median number of total coliform organisms shall not exceed 230/100 ml. May be used to irrigate fodder, seed, or processed food crops or Class E uses. Public access is restricted. Site specific See Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (IDEQ, 2006d). Site specific See Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (IDEQ, 2006d). No effluent is allowed to be applied to surface waters in circumstances where an NPDES permit is required. Grazing is not allowed. TABLE Class E Effluent Type Treatment Requirements Disinfection Permitted Uses Access Restrictions Signing and Posting Buffer Distances Grazing At least primary treatment effluent quality. Description Total coliform organisms up to too numerous to count. May be used to irrigate forested sites. Public access is restricted. Site specific See Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (IDEQ, 2006d). 1,000 feet to inhabited dwellings and area accessible to the public. No effluent is allowed to be applied to surface waters in circumstances where an NPDES permit is required. Grazing is not allowed Consent Order The City of McCall s Wastewater Treatment Facility currently operates under the provisions contained in a Consent Order between IDEQ and the City. The Consent Order is authorized pursuant to the Idaho Environmental Protection and Health Act, Idaho Code Sections to , and Section 401 of the CWA. The consent order eliminated McCall s treated wastewater discharge to the NFPR except as allowed under the emergency provisions contained in the NPDES permit. This action achieved the zero discharge 4-16 REVISED DRAFT BOI DOC/KM

17 requirements for McCall s Wastewater Treatment Facility contained in the Cascade Reservoir Watershed Management Plan approved by the EPA as a TMDL in May The original Consent Order has been modified twice, and is now referred to as the Second Amended Consent Order. The Second Amended Consent Order is presented in Appendix B. Among other topics, the Second Amended Consent Order contains the wastewater treatment and discharge requirements for the McCall Wastewater Treatment Facility as summarized below: McCall must use their wastewater treatment and storage facilities, and only discharge to the NFPR as allowed under the NPDES permit. Treated wastewater discharged to the J-Ditch mixing station must comply with the following at a point downstream of the chlorine contact basins: Median of total coliforms of 2.2 per 100 ml on a monthly basis, with a single sample maximum of 23 per 100 ml. Total coliform shall be measured on at least a weekly basis at the mixing station. Free chlorine residual of 1 mg/l, minimum, measured daily. Total phosphorus, orthophosphorus, total Kjeldahl nitrogen (TKN), nitrate nitrogen, biochemical oxygen demand (BOD), and total suspended solids (TSS) are to be monitored monthly at the mixing station. The J-ditch shall be used to convey all treated wastewater to the maximum extent practicable during the irrigation season. The percentage of treated wastewater mixed with irrigation water delivered to the agricultural fields is not to exceed 33.3 percent. 4.3 Future Effluent Limitation Scenarios The previous sections outlined the current regulatory basis for wastewater treatment and discharge established by the federal and state requirements that are currently in place. Particularly relevant to wastewater facilities planning is understanding the likelihood for revisions to the federal and state discharge requirements. Ultimately, the wastewater facilities plan must prepare alternatives that will not only meet today s regulatory environment, but also provide flexibility to meet as yet undetermined and undefined discharge requirements Discharge Options Wastewater treatment facilities must treat wastewater to acceptable levels prior to discharge to the environment. Treated wastewater is discharged to air, to surface water, to the subsurface, and to land application for beneficial use Discharge to the Air Discharge to the air is typical of wastewater storage ponds designed to rely totally upon evaporation as method for liquid discharge. These treatment systems require that the net BOI DOC/KM REVISED DRAFT 4-17

18 evaporation from the pond exceed the influent to the pond in order to contain the liquid within the pond. These treatment systems are often referred to as total containment ponds. Enhancing the evaporation rate is another way to discharge to the air. Thermal evaporators convert the water component in wastewater to clean vapor for steam release. On average 95 percent of the original wastewater is evaporated leaving only a small residue requiring disposal. Typical thermal evaporation applications include disposal of cleaning solutions, rinse water, machine coolants, acid and caustic rinses, air compressor condensation and floor scrubber water. Thermal evaporator systems are limited to small volumes and not practical for large flow wastewater streams like McCall. Mechanical evaporators depend greatly on weather conditions such as ambient temperatures, relative humidity, and wind speed. Evaporation rates can range from 20 percent to as high as 85 percent depending on these conditions. Floating style adjustable type evaporators can continue to evaporate in the same conditions because the spray plume is closer to the pond surface and is more likely to drop back into the pond instead of on surrounding vegetation Discharge to Surface Water Wastewater treatment facilities may discharge treated wastewater into surface waters in some cases. The NPDES permit program sets the requirements and issues permits for discharges to surface waters. The NPDES permits specify pretreatment requirements and limits to ensure that the discharge does not harm water quality or public health. Discharging to surface waters is a common form of treated wastewater discharge in Idaho. Based on the Cascade Reservoir Watershed Management Plan and the Second Amended Consent Order, a discharge to the North Fork of the Payette River watershed by the City of McCall is precluded, except under emergency conditions and then only after permission from IDEQ is obtained. Given the history of water quality in Cascade Reservoir and the previous wastewater facilities planning for McCall, it is clear that obtaining a permit for a treated wastewater surface discharge to tributaries of Cascade Reservoir is unlikely. The TMDL process for the reservoir is in its third phase, plan evaluation and modification Subsurface Discharge Subsurface discharge occurs when treated wastewater is discharged under the ground surface. Individual On-Site Systems The most common example of subsurface discharge is individual onsite treatment systems that use drain fields from septic tanks. Idaho IDEQ reports that about 36 percent of all residences in Idaho discharge to the subsurface using individual septic tanks and drain fields. However, septic tanks are most applicable in rural or low-density situations, and they are not consistent with much of the City s Comprehensive Plan (City of McCall, 2000). Large Soil Absorption Systems A large soil adsorption system is a subsurface disposal system designed to receive 2,500 gallons per day or more. Some developments such as resorts, schools, subdivisions and rest 4-18 REVISED DRAFT BOI DOC/KM

19 areas that are not close to centralized wastewater collection and treatment systems often use large soil adsorption systems to treat their wastewater. As with an individual system, a large soil adsorption system must be permitted by the local Health District, and the plans and specifications prepared by an engineer must be approved by IDEQ. Large soil absorption systems are mostly applicable in low-density situations, and they are not consistent with much of the City s Comprehensive Plan (City of McCall, 2000). It is not likely that large soil absorption systems represent a viable alternative for a long-term solution to wastewater treatment and disposal. Ground Water Recharge For any type of ground water recharge system, the treated wastewater must meet ground water quality standards per IDAPA , referred to as the Ground Water Quality Rule. For these types of ground water recharge systems using Class A effluent reclaimed wastewater, ground water recharge site locations shall be a minimum on one thousand feet from any down gradient drinking water extraction well, and shall also provide for a minimum of 6 months time of travel in the aquifer prior to withdrawal. Additional permits are required from the Idaho Department of Water Resources for ground water injection wells. McCall could treat all or a portion of its wastewater to Class A effluent and inject it into the ground water for disposal. In addition, the injection could be accomplished during the winter, when irrigating with Class A effluent is precluded because of weather Rapid Infiltration Rapid infiltration is a high rate land application system with a subsurface discharge. Following pretreatment, wastewater is applied from 20 to 600 feet per year for percolation through the soil. The hydraulic application rate is dependent upon the wastewater characteristics; permeability of the soil; depth to ground water; horizontal conductivity of the soil and ground water system; and chemical and physical characteristics of the soil system. Unless the percolated water is collected and discharged to surface waters, the percolated water is considered ground water and must comply with the Ground Water Quality Rule at the point of compliance. After an initial screening of alternatives, a high rate land application system was the recommended alternative in the Facility Plan Report (JUB, 1996a). The acceptability of the high rate land application system was contingent upon its ability to remove phosphorus, and a pilot study was to be undertaken to determine performance and system sizing. Pursuit of the high rate land application alternative was subsequently dropped from further consideration based on regulatory review. Among many other things, obtaining a land application permit for rapid infiltration of treated wastewater for subsurface discharge will likely require the removal of nutrients prior to rapid infiltration. Another wastewater treatment project in Valley County is proceeding with the design of rapid infiltration disposal of treated wastewater with effluent total phosphorus less than 0.1 mg/l and total nitrogen less than 10 mg/l on a monthly average prior to rapid infiltration. BOI DOC/KM REVISED DRAFT 4-19