This is a PDF of the letter sent by four Senators; Senator Grassley, Senator Thune, Senator Hoeven, and Senator Johanns
to Assistant Secretary Mine Safety & Health, Joe Main.

 

This is the PDF of Joe Main's response to the four senators' letter above:

 

 

This appears to be a complete non-answer from Joe Main to the U.S. Senators' questions ! Please note that they requested the Asst. Sec. to reply to all 47 questions by late August. He did not! $afepro