North Carolina Administrative Code › Title 15A - Environmental Quality › Chapter 02 - Environmental Management › Subchapter U - RECLAIMED WATER › Section .0400 - DESIGN STANDARDS › Section 02U .0402 - DESIGN CRITERIA FOR DEDICATED RECLAIMED WATER TREATMENT FACILITIES

Current through Register Vol. 39, No. 2, July 15, 2024
(a) In addition to the design criteria
				  established in Rule .0401 of this Section, the requirements in this Rule shall
				  apply to all new and expanding dedicated reclaimed water treatment
				  facilities.
(b) Each facility,
				  except for those using septic tanks or lagoon treatment, shall provide flow
				  equalization with either a capacity based upon a representative diurnal
				  hydrograph or a capacity of 25 percent of the daily system design
				  flow.
(c) Dual facilities shall be
				  provided for all essential treatment units.
(d) Effluent from the treatment facility
				  shall be discharged to a five-day side-stream detention unit if either the
				  turbidity exceeds 10 NTUs or if the permitted pathogen levels cannot be met.
				  The facility shall have the ability to return the effluent in the five-day
				  side-stream detention unit back to the head of the treatment
				  facility.
(e) The public shall be
				  prohibited access to the wastewater treatment facility or the five-day
				  side-stream detention unit.
(f) The
				  storage and five-day side-stream detention units shall have either a liner of
				  natural material at least one foot in thickness and having a hydraulic
				  conductivity of no greater than 1 x 10-6 centimeters
				  per second when compacted, or a synthetic liner of sufficient thickness to
				  exhibit structural integrity and an effective hydraulic conductivity no greater
				  than that required of the natural material liner. Liner requirements of the
				  unit or separation distances between the bottom of the storage basin and the
				  groundwater table may be reduced if it can be demonstrated by predictive
				  calculations or modeling that construction and use of the unit will not result
				  in contravention of assigned groundwater standards at the compliance
				  boundary.
(g) By-pass and overflow
				  lines shall be prohibited.
(h)
				  Multiple pumps shall be provided wherever pumps are used.
(i) A water-tight seal on all treatment and
				  storage units or two feet of protection from the 100-year flood elevation shall
				  be provided.
(j) 30 days of
				  residual storage shall be provided.
(k) Utilization areas shall be designed to
				  maintain a one-foot vertical separation between the seasonal high water table
				  and the ground surface.
(l)
				  Influent pump stations shall meet the sewer design criteria set forth in
				  15A NCAC
				  02T .0300.
(m) Domestic, commercial, or industrial
				  dedicated reclaimed water systems, including single-family residence
				  facilities, with flow less than 1,000 gallons per day, are exempt from meeting
				  Paragraphs (c) and (h) of this Rule, if repair or replacement of essential
				  treatment units can be completed within five days.
(n) Facilities shall be provided with a flow
				  meter to measure the volume of treated reclaimed water applied to each
				  field.
Authority
					 G.S.
					 143-215.1;
					 143-215.3(a);
Eff. June 18, 2011;
Readopted Eff. September 1,
					 2018.