At the end of 2001, Southeast Corridor Constructors began the project of widening I-25 through the city of Denver. Major digging for new bridges and light rail left much of the dirt displaced in large piles around the project. Because of NPDES Phase II potential restrictions and fines, Southeast Corridor Constructors and Revex/Bowman worked together to find a solution to stabilize some of the dislodged soil in June 2002. An area at University Blvd. and I-25 was chosen for the test plot. Two hills around a drainpipe area were sprayed with Guardian Soil Stabilizer. On September 13, 2002, a major rain event dropped an inch of rain in 30 minutes, flooding I-25 under the Logan Street Bridge. The existing drainage system under the Logan Street Bridge was clogged by sediment that ran off the stock dirt piles and into the street in a short amount of time. Below are pictures of two different areas on the I-25 corridor. The top set of pictures are of a hill stabilized with Guardian and the bottom set of pictures are of a hill at Logan Street that was left unstabilized.