Mark and Tamara Miller were pleased to move into their new 5-bedroom home, complete with an on-site wastewater reuse system. Poor soil conditions, setbacks, and limited area left the Millers with on-site reuse as the only option to develop their Raleigh North Carolina homesite. Since this would be one of only a few permitted residential reuse systems by the North Carolina Department of Environmental Quality (NCDEQ), many homeowners would be leery of such a system. However, the Millers embraced the idea as it would allow them to build in their desired location and be environmentally friendly by irrigating their highly treated reuse quality wastewater throughout their property.
The initial 600 gallons per day reuse system consisted of a membrane bioreactor (MBR) which could not meet the required effluent criteria on a consistent basis. This forced the NCDEQ to require the Millers to bring the system into compliance. Over a two-year period, the manufacturer, equipment supplier, and installer David Brantley & Sons, Inc. worked to bring the system into compliance without success. Cory and Shane Brantley, the installers and operators of the system reached out to Gary MacConnell, P.E. of MacConnell & Associates, P.C. for advice on bringing the system into compliance. Working together, the Brantleys and MacConnell felt that the best option would be to replace the MBR treatment system with an E-Z Treat recirculating media system which has NSF/ANSI 40: Residential Onsite Systems, NSF/ANSI 350: Onsite Residential and Commercial Water Reuse Treatment Systems, and NSF/ANSI 245: Nitrogen Reduction certifications.
In the revised design, MacConnell used as much of the original system as possible including: 1,500 gallon septic tank, 3,500 gallon upset tank, and 4,500 gallon reclaimed water storage/irrigation tank complete with duplex irrigation pumps, irrigation system (spray heads and piping), and control panel. The following components were added to the system: new 1,500 gallon septic tank to replace existing tank, 1,000 gallon septic tank, E-Z Treat Model 600 Pod, GF10 Best Polylock filter with 1/32-inch openings, Hach Model TU5300SC turbidimeter with Model SC200 controller, metering pump to feed turbidimeter, Bio-Dynamic Model XT 2000 Tablet Chlorinator, solenoid and water meter for adding supplemental potable water to irrigation tank, and modifications to control panel.
The new system has performed as designed to meet or exceed NCDEQ’s stringent reuse standards as summarized below:
Parameter | Results for 7/2/2019 |
BOD5 | <2.0 mg/L |
Fecal Coliform | ??? |
Ammonia | <0.1 |
TSS | <2.5 mg/L |
Turbidity | 2.3 NTU |
The owners are pleased with the modified system and not getting notices from NCDEQ. With the addition of supplemental potable water they are now able to meet their irrigation needs during the warmer month.
Key Players:
Owner: Mark and Tamara Miller
Engineer: MacConnell & Associates, P.C.
Installer/Operator: David Brantley & Sons, Inc.
Treatment System: E-Z Treat, Inc.
“Reuse Comes to On-Site Systems – A Success for One Family” Presentation by Gary MacConnell P.E.PDF