The Minnesota Pollution Control Agency (MPCA), St. Paul, Minn., is investigating possible violations of the organization’s rules at a landfill in Winona, Minn. According to the Associated Press, the MPCA plans to determine if it excavated the landfill before it took the required measures to ensure rain would not wash away the soil. The organization is excavating the 35-acre site, which closed in 1998, to line older portions to prevent leachate from entering the groundwater.