Current through Register Vol. 49, No. 13, September 23, 2024
Subpart
1.
General.
New construction, replacement, or existing MSTS designed under
this chapter are considered conforming if they meet the requirements of this
part. Existing MSTS constructed before February 4, 2008, are considered
conforming if they meet the requirements of this part, except for subpart
4, items D and E.
Subp. 2.
Treatment
required.
All sewage discharged from a dwelling or other establishment
not served by a system issued a permit containing effluent and discharge limits
or specific monitoring requirements by the agency must be treated according to
local ordinances that comply with this chapter, chapter 7082, and Minnesota
Statutes, section
115.55.
Subp. 3.
Public health and
safety; imminent threat.
A. To be in
compliance, all MSTS must:
(1) have treatment
processes and devices that do not allow sewage or sewage effluent contact with
humans, insects, or vermin;
(2)
disperse sewage effluent into soil or sand below final grade, with the effluent
remaining below final grade;
(3)
not discharge to drainage tile, the ground surface, or surface water or back up
sewage into dwellings or other establishments;
(4) treat and disperse sewage effluent in a
safe manner, including protection from physical injury and harm; and
(5) not have received hazardous
material.
B. MSTS must
be deemed an imminent threat to public health or safety for noncompliance with
item A and any other condition that poses an imminent threat as determined by a
qualified employee MSTS inspector or licensed MSTS inspection
business.
Subp. 4.
Groundwater protection.
To be in compliance, all MSTS must:
A. meet the requirements of part
7080.1500, subpart
4, item D;
B. not be seepage pits, cesspools, drywells,
leaching pits, sewage tanks, and treatment vessels that observably leak below
the designated operating depth;
C.
not allow viable fecal organisms to contaminate underground waters or zones of
seasonal saturation;
D. employ
nitrogen reduction processes that reduce nitrogen contribution to groundwater
as determined in subitem (1) or (2):
(1) if
the discharge from an MSTS will impact water quality of an aquifer, as defined
in part
4725.0100, subpart 21, the
effluent from an MSTS, in combination with the effective recharge to the
groundwater, must not exceed a concentration of total nitrogen greater than 10
mg/l at the property boundary or nearest receptor, whichever is closest;
and
(2) if the discharge from an
MSTS will not impact water quality of an aquifer, as defined in part
4725.0100, subpart 21, best
management practices developed by the commissioner to mitigate water quality
impacts to groundwater must be employed; and
E. not exceed a groundwater discharge of
phosphorus to a surface water that exceeds the phosphorus standard to the
receiving water.
Subp.
5.
Other conformance.
To be in compliance, MSTS must meet the requirements of items A
and B.
A. All methods and devices used
to treat and disperse sewage must be designed to conform to all applicable
federal, state, and local regulations.
B. Systems no longer in use must be abandoned
according to part
7080.2500.
Subp. 6.
System operation.
To be in compliance, an MSTS must meet performance standards
and be operated and managed according to its operating permit and management
plan, as described in part
7081.0290. To be in compliance, an
MSTS designed before February 4, 2008, must be operated according to applicable
requirements of part
7080.2450.
Subp. 7.
Compliance criteria for
systems receiving replacement components.
Components of existing MSTS that cause noncompliance must be
repaired or replaced. The repaired or replacement components must meet
technical standards and criteria in parts
7081.0110 to
7081.0280. The remaining
components of the existing system must comply with subparts
2 to
5, including subpart
4, item D, if constructed
after February 4, 2008.
Subp.
8.
Upgrade requirements.
A. MSTS in compliance with this part shall be
issued a certificate of compliance. Systems found not in compliance shall be
issued a notice of noncompliance.
B. MSTS issued a notice of noncompliance
based on criteria in subpart
3 shall be repaired or
replaced within ten months or as directed by Minnesota Statutes, chapter 145A,
whichever is most restrictive.
C.
MSTS issued a notice of noncompliance based on criteria in subpart
4 or
5 shall be repaired or
replaced according to local ordinance requirements.
D. Systems issued a notice of noncompliance
based on criteria in subpart
6 must immediately be
maintained, monitored, or managed according to the operating permit.
Statutory Authority: MS s
115.03;
115.55
