Nitrogen and Phosphorus Leaching from Growing Season versus Year-Round Application of Wastewater on Seasonally Frozen Lands.

This article cites a research study focusing on the leaching of Nitrogen (N) and Phosphorus (P) in the seasonally frozen lands due to wastewater released by food processing industries of the United States. N and P are the main causes of surface water eutrophication. The potential for N and P leaching to the ground water due to land application of wastewater increases particularly in coarse-textured soils in the northern parts of the United States. In these parts of the country soils are frozen due to winter. A large quantity of wastewater is released by the food processing industry as a result of water requirements to clean food products and processing equipment. Therefore, wastewater disposal is a major challenge to the food processing plants that operate year-round. A temporary permits have been granted by the Minnesota Pollution Control Agency in Minnesota to allow application of treated food-processing wastewater during the winter. The limits of regulation on the rates of wastewater application on cropland are usually based on crop agronomic N requirements. Pretreatment of the wastewater to reduce N concentrations probably allows higher rates of wastewater application.