NORWICH — After years of back and forth between school and municipal officials, Marion Cross School has taken steps to mitigate the issues of its failing wastewater management system that sometimes results in polluted discharge pooling up on the Norwich green.
The elementary school is considering “pre-treatment” options for the effluent that drains into the four leach fields on the western side of the Norwich green, a request for construction proposals from the school district released last week said. Pre-treatment would allow the school to continue using the existing septic system “knowing that any future breakout … will not impact public health and safety.”
Costs will be provided in the proposals themselves, which are due from vendors by 10 a.m. Tuesday.
Pre-treatment of the school’s wastewater is also required if Marion Cross is going to build its own cafeteria. The school introduced a hot lunch program for the first time this fall and now has to truck in food from Hanover rather than cooking on-site due to its limited wastewater management capacity.
The school also is looking to increase the number of staff and students using existing facilities, as meter data from the school shows that current flow levels are “considerably less” than permitted flows.
While the infrastructure of the original system, which was installed in 1988, is considered to be in good condition, and the leach fields themselves are functional, the school continues to endure effluent breakout when temperatures drop.
The four leach fields on the green are hemmed in on three sides by Main Street, Route 5 and Girard Way. The triangle of concrete causes an effluent backup when the ground freezes.
“The water can’t find its natural path out of the beds,” said Jamie Teague, the Dresden School District’s business administrator. “When it freezes all the way around the leach fields, it creates a bathtub. The effluent has nowhere to go but up.”
Beginning in the fall of 2018, the school considered a number of options beyond on-site replacement or improvement, including moving the leach field to nearby athletic fields owned by the Dresden School District, or connecting to Hanover or Hartford’s wastewater systems.
But when testing requests from Hartford prevented the issue from being on the ballot at that year’s Norwich Town Meeting, the issue got kicked down the road.
For the past two years, to prevent the overflow Marion Cross hasn’t drained into the leach fields in the colder months, from December through March. Instead the school uses a “store and dose” approach, which contains the effluent in a septic tank before it’s trucked over to a treatment plant.
“But it’s very costly to pay to get rid of the effluent that way,” said Steve Revell, owner of the Lincoln, Vt.-based environmental consulting group Lincoln Applied Geology. Revell has worked extensively with Marion Cross on the issue.
“The state has indicated to us that pre-treatment ends up eliminating a very significant portion of the bacteria, and then we’ll use ultraviolet disinfection to eliminate it completely,” Revell said. “Then when the overflow occurs we don’t need to stop using the system, because whatever is emanating from them has no significant bacterial impact.”
Marion Cross isn’t locked into one specific pre-treatment technology. “We’re looking for technology that fits the terrain,” Teague said.
A Hanover High class did a deep dive into the septic system last spring and presented pre-treatment technology options to the Norwich School Board. The group focused on low energy-intensive “living technologies,” like an algae wheel, which uses photosynthesis to clean wastewater.
“Some of the kids who were in the class went to Marion Cross,” said Jeannie Kornfeld, a Hanover High chemistry teacher who co-taught the course. This meant that they had a personal stake in the project, she said. Kornfeld herself is also from Norwich, and hopes that pre-treatment will bring an end to the intermittent wintertime closures of parts of the town green due to the contaminated discharge.
Frances Mize is a Report for America corps member. She can be reached at fmize@vnews.com or 603-727-3242.