In order to protect groundwater from seepage from manure storage facilities, lagoons and holding ponds, DEQ regulations require that all waste retention facilities be constructed of compacted or in-situ soil materials at least 12 inches thick and with a maximum permeability rating of 0.0014 inches per hour. Synthetic liner materials must be of at least 20 mils thickness. If these standards for lagoons and manure holding facilities are met, combined with the benefit of self-sealing caused by manure storage, groundwater can be adequately protected. Return to Table of Contents . V. Land Application of Manure Use of manure in combination with row crop production and improved pastures is designed to remove accumulated nutrients through the cropping system.
Animal waste is a valuable fertilizer and soil conditioner.
When managed properly, the nutrients in manure can be substituted for commercial fertilizers while saving money and protecting groundwater and surface water. Solid manure can be incorporated by tillage immediately following its application, and liquid manure slurry can be injected into the soil. Manure application should be applied near the time that planting will occur to maximize nitrogen uptake by crops and minimize the loss of nitrogen through runoff or leaching through the soil profile. Liquid manure and lagoon effluent can also be applied to land areas by irrigation over growing crops. Care must be taken, however, to prevent burning of some plants by the waste materials and to avoid excessive runoff.