HARVARD — The inventor of a new septic system that was approved for use in Massachusetts this past December was invited a Board of Health to the meeting after the board leaned about the system’s approval from interested residents.

”I am the inventor of the things you are going to see here tonight,” said David Presby.

Presby spent the March 28 meeting explaining how the Enviro-Septic system works and his testing methods. Presby also discussed two accompanying systems he was seeking state approval for as well as the bureaucratic difficulties he had with the Department of Environmental Protection.

Presby said he has seen many failed systems in the 20 years he has been in the septic system business. The septic systems people have been using for the past 100 years are pipe-and-stone systems. These systems use a large buried leaching field of stone as a place for bacteria to grow and remove toxins from the water that passes through them before reaching the water table.

Solids that go through the septic systems seal the soils that the water should pass through and can coat over the bacteria that should be processing the water, said Presby.

”This is what causes systems to fail,” he said.

He then went into the details of the Enviro-Septic System, which was recently approved for general use in Massachusetts. The system is comprised of a series of interlocking tubes, which can be made to fit into unconventional spaces or on slopes. They can also be up to one-sixth of the size of a conventional system.

The tubes allow the wastewater to cool, separating out solids. The tubes are then encased in a mat of fibers that provide improved surface area for the necessary bacteria to grow on.

”What I’ve developed is an ecosystem for the bacteria to use,” said Presby.

Presby tested the system in Canada alongside a conventional system because, due to the cold, it is one of the least hospitable places for the bacteria to grow. Presby said he wanted to test them under the worst conditions at maximum usage. The Canadian government supplied an independent third party to observe the study.

”It is 100 times safer to use this than conventional pipe-and-stone,” said Presby.

Presby’s study showed that the contaminants coming out of the Enviro-System were considerably lower than the conventional system. Some were even so low that they could not be measured. The only number that was higher were nitrates and nitrites, a result of the faster decomposition.

”I’ve probably done more testing than anyone in the country on septic systems,” he said.

Presby and his company, Presby Environmental Inc., function out of New Hampshire where 75 percent of all McDonald’s fast food restaurants use the Enviro-Septic system. Ninety percent of all new systems being installed in that state are Enviro-Septic as well. The system has also been approved in Maine, Vermont, Quebec and Indiana. There are currently 850,000 Enviro-Septic systems in the ground.

The basic system has been approved in Massachusetts. Presby is currently working with the Department of Environmental Protection office in Boston on approving two related systems as well.

Presby expressed some frustration during the meeting about the approval process, as he has been working with the system here for years trying to get it approved. Most of the difficulty he has run into is because the current regulations for septic system still revolve around the 100-year-old pipe-and-stone technology.

Regarding the regulations that still surround septic systems, Presby said, “You need to go to your local authorities first.”

Presby also told residents that if they wanted the septic regulations changed to accommodate the newer technology they should talk to their state representatives.