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Technology cells down below the photozone, reducing or eliminat- ing summer blooms (see Figure 1, right). Another two horse- power blower feeds air to eight fine-bub- ble diffusers located below and forward of the coarse bubble water moving diffuser bars. Because the fine bubbles are too small to rise through the Figure 1: The water-moving aerator by Reliant Water Technologies moves more than 9 million gallons of water per day. The weight of the water makes the sludge a constantly moving fluid mass along the lagoon bottom, releasing gases and allowing natural bacteria to break down organic solids. Another blower provides DO through fine bubble diffusers that are placed forward and below the water moving diffusers. coarse bubbles and turbulence on the surface, they are car- ried horizontally forward for 25 to 35 feet, diffusing dissolved oxygen into the water. Due to the water column becoming free of polluting ammonia, nitrogen, and hydrogen sulfide gases, the water can hold more oxygen, thus improving water quality overall. Successful installations of water-moving aerators have shown the following results: — Midwestern 28-acre segmented municipal lagoon system • Problem: Could not meet effluent permit requirements. • Resolution: Four WQA units reduced effluent ammonia, BOD, and TSS to the point that the lagoons were in compliance within eight months. —Southeastern 2-acre chicken-rendering lagoon • Problem: Extremely high ammonia and an inability to hold DO with 4-20HP aerators. • Resolution: Turned 2 large aerators off, and a WQA unit cut ammonia in half and brought DO to over 3 PPM. —Northeastern 3-acre racetrack infield lagoon • Problem: Extremely high fecal coliform and E. coli counts leaving the lagoon during the racing season • Resolution: One WQA unit reduced both fecal coliform and E. coli counts over 99% during the racing season. — Eastern 1/4-acre hog waste lagoon • Problem: Wanted to use lagoon water for pen wash- down, but sludge was breaking the surface of the lagoon — and ammonia, nitrogen, phosphates, and BOD were extremely high • Resolution: In 60 days, one WQA aerator leveled the sludge in the lagoon to 3 feet under the surface, while at the same time reducing all the residual components in surface water from 50% to 70%. Conclusion Wastewater lagoons, both municipal and industrial, have been proven to be an effective waste treatment technol- ogy for many years, if the land is available. But, because of their low level of technology, they have a tendency 44 Water Online The Magazine, Wastewater Edition ■ wateronline.com Jim Dartez is the president and CEO of Reliant Water Technologies. The company is located in New Orleans, LA, and can be reached at (504) 400-1239 or jdartez@reliantwater.us.com. to be neglected and burdened with mini- mal attention. After a number of years, if effective attention is not provided to the lagoon, problems become apparent and effluent quality falls out of compli- ance or becomes an ongoing problem. One of the major problems facing lagoon owners, has been the inability to effectively mix the lagoon in such a way as to allow for the sludge to become evenly distributed around the lagoon. This lack of total mixing causes the sludge to form into mounds that hold undigested organic solids. The mounds also hold large amounts of waste gases that have a tendency to degrade the lagoon's water quality, and feed intense algae blooms that only add to the problems. Standard aeration technologies have not focused on mixing, so they do little, if anything, to address the sludge buildup problem. But a new patented design of a low-powered air-lift-based aerator has proven to use the weight of slow-moving water to break up sludge mounds located on the lagoon bottom. Eventually, tons of slowmoving water turns the sludge in the lagoon into a fluid bottom layer readily accessible to natural bacteria. While the bacteria digests the organic solids in the sludge, the waste gases are oxidized in the water column. This unique aerator, which uses a total of only 4 HP of energy, also adds oxygen to the water at a rate of over 1.5 lbs of DO per HP/hr. At a time when the economies of small communities and rural industries do not allow for lagoon upgrades and overhauls, this new low-powered, low-priced water-moving aeration technology is: • Providing lagoon owners a low cost way to get back into compliance • Rehabilitating old lagoons that have been considered out of date • Providing lagoon owners with another, lower-priced answer to lagoon overhauls other than vacuuming or dredging.