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Summary of Non Discharge Alternatives. Division of Water Quality Aquifer Protection Section. Single Most Important Take-Home Point. Waste water is a resource! When properly managed treated wastewater can provide a beneficial reuse.
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Summary of Non Discharge Alternatives Division of Water Quality Aquifer Protection Section
Single Most Important Take-Home Point • Waste water is a resource! • When properly managed treated wastewater can provide a beneficial reuse. • Treated wastewater effluent discharged to a river (Lumber) is a resource to those down stream. • Treated wastewater applied to the land has potential benefits to your community.
Overview • Non-Discharge - Land Application Unit • Factors for the Feasibility of Non-Discharge • Non-Discharge Systems (15A NCAC 02T ) • Irrigation Systems (.0500) • Single Family Residence (.0600) • High Rate Infiltration (.0700) • Reclaimed Water Systems (.0900) • Decentralized Wastewater Systems
Who Are We andWhy Are We Here? • Responsible for permitting and enforcing compliance for any wastewater system that does not discharge into waters of the State, or subsurface disposal (Onsite WW by DEH).
Who needs a Non-Discharge System? • Unable to connect to local sewer • Subsurface system rejected (SFR only) • County Health Department • On-Site Wastewater (Division of Environmental Health) • Discharge system rejected (Surface Water) • Must show that Non-discharge is not feasible before pursuing NPDES permit. • Does not comply with NPDES regulations • No nearby surface waters • Reclaimed wastewater applications to replace potable water • Conjunctive Use (Golf courses, industrial applications, non-potable indoor plumbing) • Recycle Systems (closed-loop)
What Controls The Feasibility of A Non Discharge System? • $$$$ • Soil Characteristics • Agronomic Rates • Storage Requirements • Setbacks • Design Criteria
Soils Characteristics • Maintain an acceptable loading rates based on saturated hydraulic conductivity. • Maximum irrigation rates. • Proper design and operation prevents runoff, ponding and groundwater mounding. Courtesy of the Maryland Envirothon Soils Manual
Agronomic Rate • Maintain an acceptable nutrient loading based on predicted uptake by vegetation. • Updake determined by Realistic Yield Expectation (RYE)
Storage Requirement / Water Balance • The storage requirement is intended to allow adequate storage when application is prohibited (during rain, snow and freeze events). • Based on • Precipitation • Evapotranspiration • Drainage (obtained from the KSAT value) • Run-off
Setbacks • The minimum separation between portions of the treatment and disposal system and physical features. • Surface water • 200 feet – High Rate Irrigation • 100 feet – Spray/Drip Irrigation • 25 feet – Reclaimed water • Property Line • 150 feet – Spray Irrigation • 50 feet – Drip Irrigation • 0 feet – reclaimed water • Habitable residents • 400 feet - spray irrigation • 0 feet - reclaimed water
Design Criteria • Effluent Quality • BOD • TSS • Turbidity (Reclaimed) • Ammonia • Nitrate • Fecal Coliform • Upset Pond (Reclaimed) • Flow Equalization (25% of inf.) • Power Reliability
What is Wastewater Irrigation System? • Controlled surface application of wastewater effluent on vegetated land surface. • Application utilizing spray heads or drip system • Use of natural ecosystems to attenuate/assimilate wastewater effluent • Atmosphere (evaporation / volatilization) • Soil (filtration) • Plants (nutrient uptake / mineralization) • Microorganisms (degradation).
What is Non-Discharge High Rate Infiltration System? • Controlled surface application onto the land or basin at an application rate that meets the following rates: • > 1.75 inches/week Coastal • > 16.8 inches/week Non-Coastal • Minimal use of natural ecosystems to attenuate/assimilate wastewater effluent • Can be applied at rates > agronomic rates • Greater setbacks than regular irrigation system • More Stringent effluent limits than regular irrigation.
Factors for Utilizing High Rate Infiltration Systems • Decreased disposal area requirement • Not required to meet Agronomic Rates • Must meet Ammonia and Nitrate Effluent limits • Greater Setback Requirements
What is a Reclaimed Water System? • The utilization of tertiary treated wastewater used in a beneficial manner and for the purpose of conservation of the States water resources. • Beneficial Use May include: • Irrigation of Golf Course, • Irrigation of Parks or Public Property, • Dust Control, • Soil Compaction, • Cooling Water.
Reclaimed Water Utilization Requirements (2T .0910) • Irrigation type utilization: • Residential lawns, golf courses, parks, cemeteries, schools • Commercial or industrial grounds, • Landscape areas, highway medians, roadways • Industrial and non-irrigation type utilization: • Industrial process or cooling water • Decorative ponds or fountains • Fire fighting or suppression • Dust control, street sweeping soil compaction • Individual vehicle washing for personal purposes • Shall not be used for: • Irrigation of direct food chain crops • Swimming pools, hot tubs, spas, or similar • Direct reuse as a raw potable water supply
Reclaimed versus Standard Irrigation • Disadvantages: • More costs in meeting more stringent effluent standards. • More costs in meeting more stringent design requirements. • Advantages: • Higher quality effluent • Receive a beneficial use of the effluent. • Replaces the use of potable water. • Less land requirements due to reduced setbacks. • Reduced requirements on restricted access. • Reduced Setbacks.
Reclaimed Water Conjunctive Use • Other wastewater utilization or disposal methods are available to the facility at all times. • Facility is permitted for both the originally permitted disposal method and for a beneficial use of reclaimed water. • Reclaimed water option is not necessary to meet the wastewater disposal needs of the facility
Reclaimed Water Distribution Lines - Design Requirements (2T .0909) • All piping, valves, etc. are either: • Color coded purple (i.e., Pantone 522), or • Have Warnings stating “CAUTION: RECLAIMED WATER – DO NOT DRINK”. • Cross Connection Control
Decentralized Wastewater Systems • They include • single-home onsite systems • cluster systems that may serve many hundred of homes (or equivalent flows). • Serve entire communities or multiple communities. • Systems that collect, treat and reuse or dispose of wastewater at or near its point of generation (Crites and Tchobanoglous 1998).”
Decentralized Wastewater Systems • Advantages • Improved treatment compared to septic systems. • Decreased cost for transporting of wastewater compared to a centralized system. • Community controls system – sense of ownership. • Operator requirements often result in decreased operational expenses. • Provides flexibility in system design to meet the specific conditions of the site. • May provide better watershed maintenance by minimizing the transfer of water between watersheds.
Decentralized Wastewater Systems • Disadvantages • Capital and operational costs spread out among fewer users. • Less resources to address operational problems • Homeowners often have more responsibility to maintain facility. • Transfer of ownership does not always result in proper notification of responsibilities to new owner.
Single Most Important Take-Home Point • Wastewater is a resource! • When properly managed treated wastewater can provide a beneficial reuse. • Treated wastewater effluent discharged to a river (Lumbar) is a resource to those down stream. • Treated wastewater applied to the land has potential benefits to your community.
For More Information • Land Application Unit • Spray irrigation, reclaimed water, etc. • Web Site: http://h2o.enr.state.nc.us/lau/main.html • Phone: (919) 733-3221 • NPDES Unit • Surface water discharge • Web Site: http://h2o.enr.state.nc.us/lau/main.html • Phone: (919) 733-5083 • Division of Environmental Health • Septic tank with subsurface discharge • Website: http://www.deh.enr.state.nc.us/osww_new/new1//index.htm • Phone: (919) 733-2895