Current through Register Vol. 30, No. 38, September 20, 2024
A. A 4.13 General Permit allows for the use
of a separated waste-water streams, denitrifying system for a dwelling.
1. Definition. For purposes of this Section a
"denitrifying system using wastewater streams" means a gravity flow treatment
and disposal system for a dwelling that requires separate plumbing drains for
conducting dishwasher, kitchen sink, and toilet flush water to wastewater
treatment tank "A" and all other wastewater to a wastewater treatment tank "B."
a. Treated wastewater from tanks "A" and "B"
is delivered to an engineered composite disposal bed system that includes an
upper distribution pipe to deliver treated wastewater from tank "A" to a
columnar celled, sand-filled bed.
b. The wastewater drains downward into a sand
bed, then into a pea gravel bed with an internal distribution pipe system that
delivers the treated wastewater from tank "B."
c. The entire composite bed is constructed
within an excavation about 6 feet deep.
d. The system operates under gravity flow
from tanks "A" and "B."
e. An
engineered sampling assembly is installed at the midpoint of the disposal line
run and at the base of the composite bed during construction to monitor system
performance.
2. An
applicant may use a separated wastewater streams, denitrifying system where
total nitrogen reduction is required under this Article before release to the
native soil.
B.
Performance. An applicant shall ensure that a separated waste-water streams,
denitrifying system is designed so that the treated wastewater released to the
native soil meets the following criteria:
1.
TSS of 30 milligrams per liter, 30-day arithmetic mean;
2. BOD5 of 30
milligrams per liter, 30-day arithmetic mean;
3. Total nitrogen (as nitrogen) of 30
milligrams per liter, five-month arithmetic mean; and
4. Total coliform level of 1,000,000
(Log10 6) colony forming units per 100 milliliters, 95th
percentile.
C. Notice of
Intent to Discharge. The applicant shall comply with the Notice of Intent to
Discharge requirements in
R18-9-A301(B)
and
R18-9-A309(B).
D. Design, installation, operation, and
maintenance requirements. The applicant shall comply with the applicable
design, installation, operation, and maintenance requirements in
R18-9-A312,
R18-9-A313(A),
and
R18-9-A313(B).
E. Reference design.
1. An applicant may use a separated
wastewater streams, denitrifying system achieving the performance requirements
specified in subsection (B) by following a reference design on file with the
Department.
2. The applicant shall
file a form provided by the Department for supplemental information about the
proposed system with the applicant's submittal of the Notice of Intent to
Discharge.
