Paint Dumping in our community . Is this Legal or Illegal ?

It was brought to our attention from a community member that 

there is paint dumping of over 200 gallons of Oil Based and Latex paint in a dug area

in the ground behind the building of the San Jacinto Unified School District on

the property of 2045 S San Jacinto Ave, San Jacinto, CA 92583

We had a pilot fly over the area and got the following area footage.

The Community is wanting answers on why this is taking place instead of being 

disposed properly.