(May 17, 2019) Aiming to reduce use of chemical fertilizers at Eagle’s Landing Golf Course, Worcester County officials are teeing up a request with the Maryland Department of the Environment to amend the Mystic Harbour Wastewater Treatment Plant discharge permit to increase nitrogen levels and eliminate nutrient concentration limits for monitored injection wells.
Public Works Director John Tustin said the county recently received state approval after sending a formal request in April to reopen the discharge permit, which will require subsequent legal notice prior to a public hearing.
“We received the draft permit that revises the level of nitrogen,” he said. “There will be no negative impacts on the environment as a result of these changes.”
Among the changes outlined in an April 4 letter from Deputy Director of Public Works John Ross to MDE officials requesting the discharge permit be reopened were a pair of counterbalancing changes to allowable nitrogen levels, including increasing the monthly discharge concentration from 3 milligrams per liter (mg/l) to 5 mg/l, while also reducing the maximum monthly flow from 250,000 gallons per day (gpd) to 150,000 gpd.
In the letter, Ross said state guidelines for golf course nutrient management recommend an annual maximum of 0.7 pounds of total nitrogen per thousand square feet of application. Under that standard, the roughly 98 acres encompassing Eagle’s Landing Golf Course would be able to accept just under 3,000 pounds of nitrogen yearly.
Ross noted the current Mystic Harbour discharge permit allows a monthly flow rate of 81,000 gpd at a concentration of 3 mg/l, which yields roughly 740 pounds of total nitrogen at Eagle’s Landing.
At roughly a quarter of potential capacity, the concentration levels are significantly less than recommended, Tustin said.
“If we were to keep that permit level in place and spray irrigate on Eagle’s Landing … the golf course operator would have to come back and apply liquid nitrogen to meet their growing needs,” he said.
Tallying up the outcome of boosting allowable nitrogen concentrations to 5 mg/l, which is on par with the Glen Riddle Golf Club in Berlin, would result in more than 1,200 pounds of nitrogen at Eagle’s Landing, Tustin said.
“Which is still less half the maximum recommended loading,” he said.
The Mystic Harbour treatment plant employs injection wells to dispel up to 250,000 gpd of effluent, which could be scaled up to at least twice that capacity if future demand warrants.
The injection wells deliver water underground for later applications, such as irrigating golf course greens.
The other change sought for the Mystic Harbour discharge permit would eliminate allowable yearly average concentrations of nitrogen, nitrite, phosphorous chloride and total dissolved solids for monitored injection wells.
“They’re just ground water monitoring wells, they’re not drinking water wells,” he said.
Tustin said nitrogen and other nutrient levels are closely monitored in the Mystic Harbour effluent, with the currently mandated limitations at injection wells problematic due to environmental challenges.
“We have exceeded the permit limit in chloride (or salt),” he said.
The violations, which stem from injection wells where effluent disposal has yet to occur, are primarily due to proximity to and influence from Sinepuxent Bay, where background levels of chloride and total dissolved solids are environmentally boosted, Tustin said.
Tustin said the Mystic Harbour effluent was tested for chloride this March and registered a chloride level of 63 mg/l, which is within allowable concentrations for areas served by a public-water system.
“Being the ground water monitor wells are imbedded into the ground water near the bay, it’s bound to be salty,” he said.