Auger holes shall not extend closer than 500 feet (measured horizontally) to any abandoned or active underground mine workings, except as approved in accordance with § 816.79 of this chapter.
30 C.F.R. §819.21
Auger holes shall not extend closer than 500 feet (measured horizontally) to any abandoned or active underground mine workings, except as approved in accordance with § 816.79 of this chapter.
30 C.F.R. §819.21