Interstate 70 has been under study by Transportation Department officials for months – with seven possible scenarios for improving the highway. The Department says widening the highway to include a median wide enough to build some high-speed future transportation systems would be the best idea. The first environmental impact study has been finished and so surprises have been found. A Department spokesman says a lot of potential environmental problems are avoided by expanding I-70 within the existing corridor. The Department hopes all studies will be completed within three years.