The Ins and Outs of Wastewater Lagoon Sludge Disposal

Where there are wastewater lagoons, there is sludge. If the lagoon collects too much sludge, the effluent will end up with high amounts of ammonia, biochemical oxygen demand (BOD) and total suspended solids (TSS)—plus, it stinks. Sludge disposal is the key to keeping your wastewater lagoon in Bethel, OH functioning properly and free of excess odor.

Sludge is composed of dirt, sand, inorganic compounds, heavy metals and, of course, human waste. Over time, these solids settle at the bottom of the lagoon and create a thick layer of sludge. To prevent those solids from taking over the lagoon, they must be removed on a regular basis. Here’s how the process works.

Dredging for sludge

Unlike a septic system, wastewater lagoons usually don’t have to be dredged for 20 to 30 years. However, you’ll still need to test sludge levels every five years. This allows you to monitor how quickly the sludge is building up, and its composition. Sludge composition determines how many heavy metals and nutrients are present, which will in turn determine how the sludge must be handled.

Lagoons are usually dredged for sludge—that is, the sludge is mechanically removed from the lagoon. Some wastewater lagoons use a dredge pump to make the process easier. Then the sludge is dried and sent to a landfill or other similar disposal facility. If the metal content exceeds the levels set forth in EPA Rule 503, it must be sent to a landfill.

Landfills tend to be expensive, and a single wastewater lagoon can produce thousands of pounds of sludge. Some wastewater lagoon managers opt to send the sludge to a land application facility. As long as the metal content isn’t too high, the sludge can be used for composting and fertilization. In fact, dewatered sludge is often used to fertilize alfalfa and grass hay. (Suddenly that alfalfa sprout salad may seem a lot less appealing!)

Drying the sludge is necessary, since there’s about one to four percent solids for every pound of material. In other words, for every 100 pounds of wet sludge, you’ll get one to four pounds of solid material after it’s dried. As you might imagine, it’s far more cost effective to dewater that sludge before it’s disposed of—especially because landfills price disposal by weight.

The drying process can be performed by laying the sludge out in lined drying beds, so the water can evaporate naturally. Some manufacturers are creating special bags that hold sludge and remove the solids, allowing the water to be squeezed out.

The method you use for wastewater lagoon sludge disposal depends on your specific circumstances in Bethel, OH. There are multiple ways to remove the sludge and process it for fertilizer or disposal, but it will largely depend on your land area, facilities and budget.

For more information about sludge disposal and our other sanitation services, reach out to the friendly team at Gullett Sanitation Services Inc. today. We’ll be happy to help you find the disposal solutions you need.