Each winter, the Upper Mississippi River, from about Keokuk, Iowa north, is closed to commercial navigation for about three months from the second week of December. As a result, a number of all-water movements shift to rail-barge and Peoria-Pekin area terminals experience a surge in volume. Whereas Grain Processing Corp. (Muscatine, Iowa) and Archer Daniels Midland Co. (Clinton, Iowa) ship gluten feed pellets and/or distillers dried grain supplement (DDGS, or "grain mash") down the Mississippi River from April thru November, they must ship these large volume, bulk commodities to an active barge loadout during December thru March. The Iowa Interstate Railroad (IAIS) benefits from this seasonal shift in transportation. Grain Processing Corp. and Archer Daniels Midland Co. typically route feed products via the Canadian Pacific Railway to the IAIS at Davenport, Iowa. From there, IAIS hauls this traffic to the Tazewell & Peoria Railroad's East Peoria Yard for