 Then in 1938, Material Service Corporation purchased the property and has owned it ever since.The Metropolitan Water Reclamation District of Greater Chicago (MWRD) contracted to use the quarry for stormwater overflow in 1998 as part of the Deep Tunnel or Tunnel and Reclamation Project (TARP) for the metropolitan area.The Thornton Quarry supplies 7.9 billion gal US of stormwater storage, allowing the water to be treated before release into the waterways.