WA5A. The Washington farm consisted of six barns, a milking parlor, and an office (Figure 2-2). The facility had a capacity of 4,400 milking cows and 1,200 dry cows in three units. Construction of the dairy was completed in 2002. The farm had freestall style barns, with automated flushing that occurred four times daily. Manure was transferred to the upper lagoon from a sand separation pit. The two earthen-lined settling lagoons were located to the south of the barns, and were used in alternate years. Liquids were skimmed, separated and returned as flush to the barns. One lagoon was actively filled while the other was drying or sludge was being entirely removed. The settled solids (sludge) were completely removed within a year by front-end loader. These removed solids were then strained through screens and centrifugal/screw presses with the liquid transferred to large serpentine concrete basins for secondary settling. These settled solids were then dried for bedding. Removed water from the settled solids was stored in a large clarified water storage basin for dilution of barn flush water from the lagoon. Sludge from the settling basins prior to complete removal was periodically applied on surrounding land utilizing underground pressurized pipes and a no-till soil injector. Wastewater entered the measured lagoon from the northwest corner. Gaseous emissions occur both during lagoon filling and during sludge removal. The east lagoon was rectangular with dimensions of 183 m (600 ft) by 72 m (235 ft). The west lagoon was five-sided with dimensions of approximately 183 m (600 ft) long and 83 m (271 ft) wide with the southwest corner of the lagoon cut off. The east lagoon was measured for gaseous emissions. At maximum capacity this lagoon had a liquid depth of 5 m (18 ft), surface area of 13,098 m2 (141,000 ft2) and a volume of 186,300 m3 (2,005,500 ft3). Sludge was last removed from the lagoon in 2006. Figure 2-2. Aerial View of WA5A
