Wednesday, July 23, 2014/lk
Port of Sunnyside commissioners on Monday of this week learned a new National Pollutant Discharge Elimination System permit will likely take effect in August.
Port Engineer Bob Farrell told the commissioners there hasn’t been any public comment on the matter. He said a final determination to issue the permit will be made after the Washington State Department of Ecology evaluates all comments received during the public comment period.
The new permit, explained Farrell, will allow the port district to greatly expand its wastewater processing capabilities.
The current permit allows the port district to discharge 550,000 gallons of wastewater from its sequencing batch reactors daily - between Oct.1 and June 30.
In place until Dec. 31 is an interim discharge limitation that keeps discharge rates at the current levels. “As long as we can meet quality requirements for discharge, we are permitted to discharge to surface water as soon as the permit becomes effective,” Farrell said in his report to the commissioners.
Beginning Jan. 1, 2015, under terms of the new permit, the discharge rate will increase to 1.1 million gallons per day.
The point of compliance for testing wastewater discharged on the port’s sprayfields, based on the new permit parameters, will be between 3 and 4-foot soil depth instead of at groundwater depth.
Farrell said soil nitrate concentrations are not to be exceeded in two consecutive sampling events.
Sampling, he said, must be conducted prior to irrigation in the spring and after irrigation in the fall. The new parameters limit the maximum soil nitrate levels to 30 milligrams per kilogram.
Hearing that the permit process is nearly complete, Commissioner Jim Grubenhoff said, “It’s nice to have that move forward.”