After its second malfunction this year, the Cornell Veterinary College’s animal carcass digester resumed operation this week. The digester, which overflowed earlier this month and released 1,600 gallons of hydrolysate effluent into the Ithaca sewer system, will no longer operate unattended.
The released fluid — which is the product of chemical digestion of animal remains — was diluted with 90,000 gallons of potable water and also flowed into the stormwater collection system feeding into Beebe Lake and Fall Creek.
The machine overflowed unattended for at least 14 hours before a worker observed water leaking under the door, according to a letter obtained by The Ithaca Journal from Paul Jennette, a biosafety engineer at the Veterinary College, to the New York State Department of Conservation.
Though tests showed the water to have been fully sterilized before its release, the University plans to increase monitoring of the machine.
“Monitoring data indicate that prior to the accidental discharge, the digester had completely finished its six-hour, 300-degree-Farenheit treatment cycle, ensuring there was no biological hazard associated with the release,” the University said in a statement.
The University attributed the latest malfunction to a manufacturer’s programming error, which has since been rectified.
“The manufacturer has corrected the error and modified the program to add safety checks, and has removed the feature that allowed the digester to drain and fill automatically. Those functions will no longer occur without action by an on-site operator,” the statement said.
The digester’s air vent outlet has also been rerouted to a special containment space that will keep any future overflow out of city sewers.
Original Author: Eliza LaJoie