The Iowa Department of Natural Resources (DNR) is investigating a small diesel fuel spill on Wednesday from a Union Pacific Railroad Company train. At approximately 10:45 a.m., Union Pacific contacted the Glidden Fire Department to inspect a suspected leak in refrigeration cars stopped near the Velvet Ave. crossing in Glidden. First responders found less than 10 gallons, had leaked from the units due to loose fuel caps. The spill had been cleaned up and contained by the time an environmental specialist from the DNR arrived on the scene Wednesday afternoon. Initial reports indicate no waterways were affected by the spill. The DNR is evaluating if any enforcement action will be required against Union Pacific.