A two-week trial of an odor reduction process at Marietta's wastewater treatment plant is being considered a success by plant personnel and some neighborhood businesses.
"The odor wasn't completely eliminated, but it was greatly reduced," said Al Miller, project manager with Christy and Associates, Inc., which developed several business properties near the plant.
Since a failure in the plant's sludge processing equipment occurred in January 2010, businesses in the neighborhood have had to deal with the odor of raw sludge that emanates daily from the wastewater facility.
Following a meeting with business owners from the area in early May, city officials agreed to try applying a chemical called VX-456 for two weeks to help reduce odors from the unprocessed sludge.
Wastewater superintendent Steve Elliott asked Miller to help monitor how businesses were impacted by the odor reduction experiment, which ended last week.
"We had Dave Bricker, the general manager of the Hampton Inn and Microtel, keep track of any incidents there due to the odor situation, and he said no one had declined to stay or checked out over those two weeks," Miller said.
About the odor experiment
An odor-reducing chemical-VX-456-was added to the sludge dewatering process at Marietta's wastewater treatment plant for two weeks, beginning on May 22.
Plant staff and neighboring businesses say the chemical definitely reduced the smell from the raw sludge during the two-week trial period.
Wastewater superintendent Steve Elliott plans to request funding from city council to continue application of the chemical until new sludge processing equipment is installed at the treatment plant within the next two years.
Sherry Bailey is assistant manager at the Arby's restaurant located about half a block from the wastewater plant.
"I personally hadn't noticed if there had been an improvement but maybe we've just gotten used to it," she said. "When the weather gets hot and humid you notice it the most. It seems to just hang in the air."
An employee at the nearby Applebee's restaurant said she noticed the odor hadn't been as potent over the last couple of weeks.
Elliott said the plant ran out of the chemical last week, but during the two-week trial run a monitor of gases released during the sludge dewatering process showed a significant reduction in hydrogen sulfide, which would indicate that other odorous gases were also reduced by injecting the VX-456 into the process.
"There was still some odor, but it's not nearly as bad as it was before we used the chemical," he said.
Data collected during the trial run has been sent to Siemens AG, which provided the VX-456.
"We're currently waiting for information to come back from the company which will likely include a proposal and recommendation for continued use of the chemical," Elliott said. "When that information comes back I plan to take it before a joint session of the council finance and water, sewer and sanitation committees to ask for more funding to continue the odor reduction process."
Last month Elliott said $71,000 was a rough estimate of the annual cost to continue using the chemical, but a better figure would be available once the information comes in from Siemens.
Marietta Councilman Mike McCauley, D-2nd Ward, chairs the water, sewer and sanitation committee.
"I'll vote to continue the process," he said. "We looked at the expected expense during a previous meeting, and if the process worked I believe everyone was in agreement to continue to fund it."
McCauley noted the chemical application would likely have to continue for a couple of years until new sludge processing equipment is installed as part of a multi-million-dollar upgrade currently underway at the wastewater treatment plant. The project is expected to be completed in 2015.