Excessive lagoon sludge accumulation contributes to the poor performance of any treatment system. Removing sludge from lagoon cells improves treatment and addresses violations in the Department of Environmental Quality enforcement action.
The City of Harlem, Montana has a three cell partially mixed aerated lagoon system constructed in 1985. The lagoon system discharges to the Milk River.
Stahly Engineering & Associates, Bozeman, MT and the City of Harlem staff conducted a lagoon survey in 2009. Each cell was sampled in multiple locations using a sludge judge probe assembly operated from a small boat. Solids volumes were calculated using the lagoon bottom area multiplied by the sludge depth.
WaterSolve, LLC, a national leader in dewatering operations located in Caledonia, Michigan, and a master distributor of TenCate GeoTube® products bid the project. The project was financed by a grant from the Renewable Resource Grant and Loan program of Montana’s Department of Natural Resources.
A subcontractor to WaterSolve, SRS Crisafulli, Inc., Glendive, MT, a manufacturer of sludge removal dredge systems, provided the dredge, float line, and operator/trainers to the jobsite, located on the other side of the Charles M. Russell National Wildlife Refuge.
Montana Rural Water System’s Dan Kramer offered a training program: Sludge Removal for Small System Wastewater Operators Workshop, a Continuing Education Credit for Montana Certified Operators, approved by the Montana DEQ, as part of this training and demonstration project.
The sludge removal project, completed in July, 2013, is the initial step in a comprehensive facility upgrade for the City of Harlem.