Justin VanDenEinde, left, a student at St. John's University in Collegeville, and Jennifer Ridler, a student at St. Cloud State University, clean furniture Monday at the Dorothy Olson Aquatic Center in Willmar. Summer workers and employees with the city of Willmar Public Works Department are preparing the center for its June 10 opening. The center will be open daily from noon until 7 p.m., weather permitting. Daily admission is $4. Tribune photo by Gary Miller