EPA’s DECENTRALIZED WASTEWATER MANAGEMENT GUIDELINES US EPA Office of Wastewater Management
What are Decentralized Wastewater Systems? A.K.A. . . . Septic Systems Onsite Systems Individual Systems Cluster Systems Package Plants Large Capacity Septic Systems
States Regulate These Systems... So Why is EPA Getting Involved?? Clean Water Act goals not being met Major nonpoint source of pollution Lack of funding: Need alternatives to costly centralized treatment plants Regulatory Issues, e.g., UIC, Stormwater Phase II, NPDES
Underground Injection Control Program Lawsuit addressed large septic capacity systems Cesspools were banned Large Capacity Septic Systems (LCSSs): Serve 20 or more people/day, sanitary waste only Estimated 300,000 LCSSs systems in U.S. Regulatory determination acknowledges US EPA’s Decentralized Management Guidelines as primary tool No rulemaking at this time – try management first
Decentralized Systems are a Significant Issue Nationally 21% of homes use onsite or clustered treatment systems (~ 25% of new construction) Nearly half are more than 30 years old 50% in suburban areas, rest in rural areas 5 - 15% malfunction each year 2nd highest threat to groundwater One-fourth of the households in the U.S. are served by onsite systems (primarily conventional septic systems). Well over 4 Billion gallons/day of effluent being discharged to soil, groundwater and surface waters of the U.S. About 1/3 of new construction nationally is being served by onsite systems. In some areas, the number is much higher. Small communities (less than 10,000 population) represent over 10% of the total wastewater need in this country. These communities are prime candidates for decentralized approaches. Onsite systems are not just a rural issue, however. Over half of the onsite systems in the U.S. are located in SMSA’s (cities and their suburbs).
Water Quality Problems Estuaries Groundwater National Estuary programs, Beach protection programs and Shellfish harvesting area reports all list onsite systems as being contributors to water quality degradation. - Factor in Beach Impairment: (36%) - Shellfish Bed Closures: (32%) - 168,000 viral, 34,000 bacterial illnesses per year (contaminated gw sources) Over 10,000 identified water body impairments are due to pathogen or nutrient contamination (5,281 pathogen, 4,773 nutrient impaired water bodies), and septic systems are contributors in many areas. Impaired Waters Shellfish Beds
Sewage surfacing: potential public health threat
Sewage surfacing: potential threat to water resources Madison One More Home Sewage Discharge Just before Effluent Stream Reaches Pond in Ditch Sewage surfacing: potential threat to water resources
What is Needed? Improved management, including: Better planning and system clustering Improved owner awareness Licensed/certified practitioners Appropriate, risk-based application of technology to the receiving environment Long-term operation & maintenance Inspections based on system type, location and receiving environment Effective and affordable options for difficult sites, including clustered units Consideration of all options (decentralized and centralized)
Treatment Technologies Available Media Filters (sand, gravel, peat, textile) Aerobic Treatment Units (ATUs) Lagoons Evapotranspiration Beds Constructed Wetlands UV Disinfection Others
Examples of Advanced Treatment Technologies Effluent Pumping Textile Filter Examples of some treatment options: Bottom two are variations on filtration through bed of sand, with one being a single-pass dosing filter, the other recirculates the effluent so it makes several passes through the filter; Top left is a pumping chamber which pumps effluent from a septic tank to a small-diameter collection line which serves a cluster of homes and carries the effluent to a site for treatment; Top right is a textile filter -- there are many variations on media used, such as foam, various types of gravel, plastic, and peat. Intermittent Sand Filter Recirculating Sand Filter
Dispersal Technologies Septic Tank Effluent Pumping Low Pressure Pipe Mounds Drip Irrigation Chamber System Contour Trench Pressure Dosing
Examples of Dispersal Technologies Mound System Drip Irrigation Examples of some dispersal options: For areas with high gw or poorly drained soils, a mound can be constructed for filtration and treatment of the waste before it reaches the native soil; Drip irrigation or low pressure pipe allow a uniform introduction of wastewater into the soil in controlled doses, thereby maximizing treatment by bacteria and the soil particles; Chamber systems provide a storage space for wastewater as it is filtering into the soil and make use of the trench sidewalls for making contact between the wastewater and the soil; In areas with steep slopes, narrow, shallow trenches can be constructed along the contours, with flexible pipe to carry and distribute the wastewater into the soil. Chamber System Contour Trench
Advanced Treatment Capabilities With proper management, these systems can reliably meet environmental and public health requirements, even in sensitive areas which require high levels of performance. Here’s a picture of samples from a sand filter system in Maryland, showing septic tank contents on the left and filtered effluent on the right.
New Focus: Watertight Tanks, Risers, Effluent Filters
Vision for EPA’s Decentralized Wastewater Program Decentralized wastewater treatment systems are appropriately managed, perform effectively, protect human health and the environment, and are a key component of our nation’s wastewater infrastructure Actions: Published the Management Guidelines and Handbook Facilitating implementation by industry/partners Coordinating with other health & water resource programs Encouraging & supporting certification/licensing Assisting states with management programs Promoting finding & fixing illegal and/or illicit discharges Conducting outreach and regional workshops & forums
Management’s Advantages
Elements of a Comprehensive Management Program Public Involvement Planning Performance Req’ts Training/Certification Licensing Site Evaluation Design Construction Operation & Maint. Residuals Management Inspections/Monitoring Corrective Actions Record-Keeping/ Reporting Financing
The Traditional Management Focus Permitting: prescribed limits on acceptable sites; prescribed system designs Installation: oversight of construction and installers and/or licensing, registration O & M: homeowner booklets and brochures, tank pumping info Corrective actions: repair or replacement required when complaints verified
Performance-Based Approach Siting and design: Designing a system that meets performance requirements based on site conditions rather than requiring the site to meet prescriptive criteria (lot size, soils, depth to groundwater, etc.) needed for the system System management: Management programs that provide perpetual system oversight to protect public health and water resources 4
Performance-Based Siting and Design Characterize wastewater to be treated Assess site conditions Identify design boundaries Identify desired performance requirements Determine design boundary loadings Assemble appropriate treatment train 5
EPA Voluntary Management Guidelines for Decentralized Systems Guidelines finalized in 2003 Objectives: Raise the quality of management programs Promote consistent management approaches Establish minimum levels of activity Institutionalize the management concept Covers surface and subsurface discharges For existing, new, large, and small systems
Key Concepts in Guidelines Voluntary implementation Comprehensive focus Inventories at a minimum Performance-based approach to overcome soil limitations O&M contracts and permits O&M contracts for advanced systems Operating permits for large systems, clusters, and systems in high-risk areas NPDES permits for discharging systems Find and remove illegal/illicit connections to storm sewers
Key Concepts (cont.) Increased certification/licensing Target hot spots, high risk areas, certain system types Integrate management models Progressive series of five levels As resource sensitivity and technical complexity increase, so does the management level (i.e., the intensity of the management program
EPA Voluntary Management Guidelines 5 Suggested approaches to management Homeowner Awareness Maintenance Contracts Operating Permits RME Operation and Maintenance RME Ownership/Management RME = Responsible Management Entity
MANAGEMENT MODEL 1 Homeowner Awareness of Operation and Maintenance Needs Covers conventional onsite septic systems Low environmental sensitivity i.e., adequate space, separation distances, etc. Local agency is aware of system locations Periodic operation and maintenance reminders
MANAGEMENT MODEL 2 Maintenance Contracts Electric/mechanical systems given more attention Allows for more complex options e.g., mounds and other media filters, pressure dosed systems Maintenance contracts with trained service providers
MANAGEMENT MODEL 3 Operating Permits Renewable operating permits Regular reporting and monitoring Good for more sensitive sites lakes, drinking water aquifers Dependent on maintaining performance requirements Minimum for clusters, aerobic units, large capacity systems
MANAGEMENT MODEL 4 Responsible Management Entity Operation and Maintenance Management entity responsible for O & M Systems still owned by homeowners Ensures consistent performance RME performs routine inspections & maintenance Good for very sensitive areas - recreational uses, wellhead protection
MANAGEMENT MODEL 5 Responsible Management Entity Ownership and Management Same as Model 4, except RME owns the treatment system(s) Professional management of all activities Analogous to centralized collection and treatment Allows area-wide watershed planning and management Very sensitive environments Reduces oversight by regulatory agency
Maintenance contracts Application of the Five Model Programs Environmental Sensitivity Public Health Wastewater Characteristics Treatment Complexity Increasing Risks 2 Risk Factors 1 3 4 5 Inventory & maintenance awareness Maintenance contracts Operating permits RME O&M RME ownership
Onsite and Cluster Systems Management Handbook Describes process for developing management programs Includes case studies and examples Focuses on planning and risk-based treatment options Developed by steering committee of stakeholders Audience is state/local regulators, service providers, local officials Contains fact sheets on management program elements
Organization of the Decentralized Systems Management Handbook
Other US EPA Resources Public awareness and education tools Homeowners’ Guide Case studies of management programs TWIST database for system inventories Web site containing Examples of funding Model codes and ordinances Septage management examples
Onsite Wastewater Treatment Systems Manual Supplements and updates 1980 Design Manual Promotes transition to performance-based programs Supports and complements the Management Guidelines and Management Handbook Addresses management functions to support performance-based approach
Partners and their Key Activities Water Environment Federation (WEF) Address engineering community issues National Small Flows Clearinghouse Provide technical assistance and support the state onsite regulators National Environmental Health Association (NEHA) Develop credential for installers National Onsite Wastewater Recycling Association (NOWRA) Implement performance code Implement training institute National Association of Towns and Townships (NATaT) Reach out to Members Rural Community Assistance Program (RCAP) Provide technical assistance National Association of Wastewater Transporters (NAWT) Develop training for pumpers Develop pump truck driver certification Consortium of Institutes for Decentralized Treatment Develop university curriculum
www.epa.gov/owm/onsite