The Army Corps of Engineers presented a study of navigation on theMississippi River at meeting in Davenport last night. Corps project managerGary Loss says improving the locks is a high priority.The Sierra Club is following the progress of the Corps’ study. Theenvironmental group’s spokesman Mark Beorkrem (burk’-rem) says any expansionof commercial navigation should be put on hold.Beorkrem says the environmental impact outweighs any benefits of expansion.Agricultural interests suuport the improvements to keep the costs of movinggrain down.