Using untreated parcels of soil as a control, other parcels of land were treated with chemical fertiliser and others with soil treated with sewage waste. The result was that the soil treated with sludge from Haspolat treatment plant was more fertile and the soil structure had been improved. Grain crops planted were most prolific when grown on the soil treated with sewage from the treatment plant.
A report stated that the Haspolat Treatment Plant produces 3,000 tons of treated waste sludge annually, and that the heavy metal content in the sludge is below the upper limit values. This could be an advantage to agriculturual production since the cost of chemical fertilisers has increased significantly.