News: Nation Feds say Exxon's delayed response to pipeline break made Yellowstone River oil spill worse January 2, 2013 | Modified: January 2, 2013 at 2:31 pm Leave a comment BILLINGS, Mont. (AP) — Feds say Exxon's delayed response to pipeline break made Yellowstone River oil spill worse. Sign Up for the Daily E-dition newsletter! Please enter your email address below to begin receiving the Daily E-dition newsletter. You must enter a valid email address in the field above! Thank you for signing up for the Daily E-dition newsletter! You should receive your first newsletter very soon. We're sorry, there was an error processing your newsletter signup. Please click here to visit our Newsletter Signup Center to register for this newsletter.