When the drainfield failed on a residential home outside Chapel Hill, North Carolina, the lot’s small size prevented homeowners from installing a new one. Sewer service was not available at the site, and so the owners faced the very real possibility of losing their home.
The North Carolina Department of Water Quality wanted to help the homeowners find a solution; but, to maintain public health, the DWQ had to ensure that any new system could meet local National Pollutant Discharge Elimination System standards.
Enter engineer Kevin Davidson of Agri-Waste Technology. He worked with Orenco Systems’ area sales manager Todd Harrell to devise a solution. Davidson suggested to the DWQ that the homeowners install an AdvanTex AX20-RTUV. This would provide excellent wastewater treatment through the use of a packed-bed media filter and ultraviolet disinfection, a combination that would clean the wastewater to better than secondary treatment standards.* Treated effluent from the system was expected to meet NPDES permit limits for surface discharge into a ditch or body of water, eliminating the need for a drainfield.
The DWQ approved the permit — the first time an AX-RT unit was approved for surface discharge in the state of North Carolina.
Davidson designed the new system using the homeowner’s own septic tank, a 1,000-gallon baffled concrete tank, for primary treatment. The AX-RT’s configuration eliminated the need for a discharge tank, separate UV basin, and several risers and lids.
“The AX-RT is great for those repair projects because you can just drop it in behind the existing equipment, even if the equipment is not Orenco’s,” Harrell says.
The entire installation — including all electrical, plumbing, drainage and landscaping work — took only three days. An Orenco Biotube effluent filter was placed in front of the septic tank’s outlet, and the AX-RT unit was installed behind the tank. The system discharges directly to a drainage ditch on the property.
With the success of this project, Davidson is now working on 10 other AdvanTex systems, most of which are using AdvanTex AX-RT units to allow for direct discharge.
“The AX-RT is the best unit when you look at aesthetics, installation cost, ability to treat waste, and support from Orenco,” Davidson says. “Compared to other technologies, I would grade Orenco at the top.”
For more information, visit Orenco.com or call 800-348-9843.
*NSF International Standard 40 Evaluation Report, April 2002. (Evaluation performed by NovaTec Consultants, Inc.)
