Employee of Orica initiated a successful blast. The NYS Police called Callanan's to report a bus had been hit on the NYS Thruway. MSHA was notified. It was determined that a rock pierced the roof of the W bound bus. 3 people were injured: #1 in the neck & back, #2 in the leg. #3 treated for abrasions. Victims transported to St Mary's Hospital in Amsterdam and released.