Print
Share page with AddThis

I/A Systems and Nitrogen Aggregation Loading Plan FAQs

test

What is an Innovative/Alternative (I/A) septic system?

Innovative/Alternative (IA) on-site septic systems are designed to prevent excess nutrients, such as nitrogen, from entering estuaries and freshwater ponds, by removing much of the nitrogen in wastewater before it leaches into the ground.  Under the Title 5, MA DEP must approve an I/A technology before it can be used in Massachusetts.  There are 4 categories of approval:

  • General Use systems will provide a level of environmental protection at least equivalent to that of a conventional on-site system designed in accordance with Title 5.
  • Piloting is intended to provide field-testing and technical demonstration to determine if the technology can or cannot function effectively.
  • Provisional Use approval is intended for evaluation of alternative systems that appear technically capable of providing levels of protection at least equivalent to those of a standard on-site disposal system.
  • Remedial Use systems improve existing conditions at a particular facility or facilities served by a failed, failing, or nonconforming system.

In each case, the system owner must follow the inspection and testing schedule required by the DEP in its approval letter.

Click HERE to visit the Massachusetts Alternative Septic System Test Center website.
 
What is a Nitrogen Aggregation Plan?
 

Properties located within a Zone II (See “What is a Zone II?”) as well as properties not connected to a public water source (Town water) are restricted to one (1) bedroom for every 10,000 sq ft of land area.  A Nitrogen Aggregation Plan (NAP) is a process whereby open space area (referred to as “credit land”) may be used to obtain additional bedrooms for an undersized property (referred to as “facility land”).  To qualify as "credit land", the land must meet certain criteria as outlined in MA DEP's Guidelines for Title 5 Aggregation of Flow and Nitrogen Loading 310 CMR 15.216.  The credit land must be located within the same Zone II as the facility land, and both the facility and credit land must be restricted in perpetuity through either an appropriate conservation restriction or a nitrogen loading restriction and easement.  The aggregation of nitrogen loading for on-site septic systems must be performed in an environmentally acceptable manner and in accordance with the provisions of Title 5 of the State Environmental Code, 310 CMR 15.000.  NAPs require Board of Health review and approval at a public meeting.

For information about available credit land in your area, please contact a professional engineer.