Wednesday, November 09, 2011

Lagoon Treatment of Leachate Added by Bi-County Solid Waste Management

Bi-County Solid Waste Management expects to save up to $20,000 each month with the help of its latest step toward self-sufficiency.


The Montgomery County landfill's executive director, Pete Reed, said the majority of leachate, or contaminated water, on the site will eventually be treated in the lagoon that began holding water after the May 2010 flood that shut down Clarksville's wastewater treatment plant.




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"They had to put a permit on us and start charging us $9,000 to 10,000 a month, but if we had a parameter that goes above, then we had ... surcharges that could be an additional $15,000 in that month," said Reed, who added that the landfill went above that parameter 2-3 times a year.


As those costs started to build, along with the high costs of hauling the leachate off the site, Reed said the decision was made to create a $750,000 system featuring the lagoon that holds 1.3 million gallons and will be able to decontaminate the water over a 30-day period.


Three separate pools hold the water that is pumped in from various locations throughout the site. The two pools with a white foam layer on top are anoxic zones, meaning aerators pump in oxygen, while the middle pool is anaerobic, with a pump that puts in a different mixture of chemicals.


Beginning in May of this year, Reed said micro-organisms that are trained to eat ammonia and other chemicals were added to help treat the water by releasing the nitrates and taking out any odor. Although Reed said the pools have reached the optimal amount of the "bugs" that come from Paris, Tenn., it will still be a few months before the system is fully operational.


Reed said the lagoon has already ensured the landfill won't go beyond its monthly parameters at the wastewater treatment plant, and eventually the treated water will overflow into a clarifier that will filter out the sludge and transport the clean water to a 7 million gallon holding pond adjacent to the lagoon. That water will be used for irrigation on the grass at the site, as well as the nearby woods and, if it's clean enough, into local streams.


Depending on the season, Reed said the system could put out about a million gallons each month. Before it can be used for irrigation or anything else, several samples of the water will have to be approved by the state.


Even with the new system, some leachate will still go to the wastewater treatment plant, but the cost of the permit and the manpower required will be reduced significantly. Reed said he doesn't expect the loss of income from the landfill to have much effect on the plant's bottom line, since it's expanding and gets plenty of money from industrial sources.


"We hope that by this time next year, we'll be pretty much self-contained," Reed said. "Nothing will have to go out, other than (recyclables)."


View the original article here

1 comment:

Fonso said...

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