Delaware Administrative Code
Title 7 - Natural Resources and Environmental Control
5000 - Division of Watershed Stewardship
7400 - Watershed Assessment Section
7403 - Regulations Governing The Pollution Control Strategy For The Indian River, Indian River Bay, Rehoboth Bay And Little Assawoman Bay Watersheds
Section 7403-8.0 - On-site Wastewater Treatment and Disposal System Performance Standards
Universal Citation: 7 DE Admin Code 7403-8.0
Current through Register Vol. 28, No. 3, September 1, 2024
8.1 All OWTDSs in the Indian River, Indian River Bay, Rehoboth Bay and Little Assawoman Bay Watersheds are required to reduce their nutrient wastewater loads.
8.2 Requirements for large OWTDSs having flows greater than 20,000 gallons per day (gpd):
8.2.1 All new systems shall meet Performance
Standard Nitrogen level 1 (PSN1).
8.2.2 All replacement systems shall meet
Performance Standard Nitrogen level 2 (PSN2).
8.2.3 When the operation and maintenance
permit expires for an existing system, the Department will require the system
to meet Performance Standard Nitrogen level 2 (PSN2). If the Department deems
that the OWTDS must be redesigned to meet PSN2, the owner or operator of the
system will have up to 60 months from the permit expiration date to bring the
OWTDS into compliance with the new standard.
8.2.4 Where the system location is identified
as having high potential for phosphorus mobility, new OWTDSs shall meet a
Performance Standard Phosphorus level 1 (PSP1).
8.2.5 When the operation and maintenance
permit expires for an existing system, and the system location is identified as
having high potential for phosphorus mobility, the system must comply with the
Performance Standard Phosphorous level 1 (PSP1). If the Department deems that
the system must be redesigned to meet PSP1, the owner or operator of the system
will have up to 60 months from the permit expiration date to bring the OWTDS
into compliance with the new standard.
8.3 Requirements for large OWTDSs having flows greater than 2,500 gpd but less than 20,000 gpd:
8.3.1 All new systems shall meet a
Performance Standard Nitrogen level 2 (PSN2).
8.3.2 All replacement systems shall meet a
Performance Standard Nitrogen level 3 (PSN3).
8.3.3 When the operation and maintenance
permit expires for an existing system, the system must meet a Performance
Standard Nitrogen level 3 (PSN3). If the Department deems that the large OWTDS
must be redesigned, the owner or operator of the system will have up to 60
months from the permit expiration date to bring the OWTDS into compliance with
the new standard.
8.3.4 When the
operation and maintenance permit expires for an existing system and the system
location is identified as having high potential for phosphorus mobility, the
system must comply with the Performance Standard Phosphorous level 2
(PSP2).
8.4 Requirements for small OWTDSs having flows less than or equal to 2,500 gpd:
8.4.1 All new and replacement systems shall
meet a Performance Standard Nitrogen level 3 (PSN3).
8.4.2 Department approval and use of advanced
treatment units shall be in accordance with the Regulations Governing the
Design, Installation and Operation of On-Site Wastewater Treatment and Disposal
Systems and the Innovative and Alternative System Approval Checklist.
8.4.3 All permit applications shall be
prepared in accordance with the Regulations Governing the Design, Installation
and Operation of On-Site Wastewater Treatment and Disposal Systems and these
Regulations.
8.4.4 To provide
proper operation and maintenance of the innovative and alternative onsite
wastewater treatment and disposal system, the permittee is required to adhere
to Department permit conditions. These permit conditions require mandatory
operation and maintenance for the life of the system by maintaining a service
contract with a certified service provider.
8.4.5 In instances where central sewer will
become available within five years, the requirements of Section 8.4 will be
waived after the Department receives a letter (with an approved Certificate of
Public Convenience and Necessity (CPCN) where applicable) stating when central
sewer will become available from Sussex County, the appropriate municipality,
or the wastewater utility.
8.5 Large systems will be operated and monitored in accordance with permit conditions, and the following:
8.5.1 Large systems shall be operated by a
Department licensed operator. The class level of the operator required and
frequencies of inspections will be in accordance with the Regulations for
Licensing Operators of Wastewater Facilities.
8.5.2 Large systems shall be sampled as
outlined in the permit conditions.
Disclaimer: These regulations may not be the most recent version. Delaware may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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