New Mexico Administrative Code
Title 20 - ENVIRONMENTAL PROTECTION
Chapter 7 - WASTEWATER AND WATER SUPPLY FACILITIES
Part 3 - LIQUID WASTE DISPOSAL AND TREATMENT
Section 20.7.3.603 - DESIGN; TERTIARY TREATMENT STANDARDS
Current through Register Vol. 35, No. 18, September 24, 2024
A. Tertiary treatment systems shall provide total nitrogen (TN) removal in addition to secondary treatment.
B. For lots that exceed the allowable hydraulic loading pursuant to Subsection C of 20.7.3.301 NMAC, a department approved tertiary treatment unit may be installed. The treatment unit must be capable of removing TN to a concentration equal to or less than the concentration limit calculated pursuant to Subsection C 20.7.3.603 NMAC.
C. Utilizing the standard loading equation, (flow (gpd) X conc. (mg/l) X 8.34 lbs./gal. X 365 days/yr)/ 1,000,000 = lbs./yr/ac., and assuming an average of 60 mg/l of TN in the septic tank effluent and a maximum flow of 500 gpd/ac, the following simplified equation shall be used for determining the required TN concentration allowed for a specific lot size: total nitrogen concentration (in mg/l) = [lot size (in acres) / design flow (in gpd)] x 30,000.
D. The treatment unit shall be operated in accordance with the manufacturer's specifications and department approval conditions.
E. Total nitrogen effluent testing, when required pursuant to Subsection C of 20.7.3.901 NMAC, shall meet the concentration limit calculated pursuant to Subsection C of 20.7.3.603 NMAC.
