Septic System Design

A septic system or individual subsurface sewage disposal system is a system used for the disposal of sanitary sewage into the ground which is designed and constructed to treat sanitary sewage in a manner that will retain most of the settleable solids in a septic tank while discharging the liquid effluent to a disposal field.

The design and construction of septic systems in New Jersey are governed by the Standards for Individual Subsurface Sewage Disposal Systems, State of New Jersey Administrative Code N.J.A.C. 7:9A (the Standards). There are a variety of septic systems that can be designed some of which are preferred in order to compensate for physical limitations and environmental concerns impacting the site. Sites located within the Pinelands National Reserve (Pinelands) are subjected to additional standards not otherwise required for properties located outside of the Pinelands. More particularly, the Pinelands require that new residential development on less than 3.2 acres to be designed in conformance with an approved alternate septic system. One exception to the alternate system requirement is a cluster subdivision development where lots sizes can be reduced to no less than 1 acre, but the development's lot average is 3.2 acres.

However, for non-residential development in the Pinelands, the size of the given parcel directly dictates the size of the development proposed. The Pineland's nitrate dilution model is used to determine when given certain project parameters if the nitrogen concentration in that wastewater exceeds the 2 mg/l threshold. The model takes into account soil type, size of the lot (acres), type of septic system and the anticipated amount of daily wastewater generated (gallons).

The Standards has established flow rates for a variety of uses ranging from residential dwellings to camp sites, restaurants, office buildings and much more. The various septic systems depicted in the Standards are listed below:

• Conventional Septic System
• Soil Replacement, Bottom Lined
• Soil Replacement, Bottom Lined
• Mounded Septic System
• Soil Replacement, Mounded System

Septic system design, construction or alteration is approved by the county board of health or its authorized agent. When a sewage disposal system is beyond the scope or not in strict compliance with the requirements of the Standards, the application can be submitted for a Treatment Works Approval to the New Jersey Department of Environmental Protection. This application process is lengthier and more costly.

Our experience and knowledge permits us to properly understand the applicable regulations, correctly evaluate the site's geology and its limiting horizons, and propose the most effective septic system design.