C. A natural buffer strip at least 50 feet wide must be maintained between the working edge of an excavation and any private road or right-of-way. If a private road is contained within a wider right-of-way, the buffer is measured from the edge of the right-of-way. The width of the natural buffer strip adjacent to a private road may be reduced if the applicant receives written permission from the person or persons having a right-of-way over the private road.

Except for paragraph B, the department may not grant a variance from the provisions of this subsection. The department may grant a variance from paragraph B, provided that if the variance will not result in the natural buffer strip being reduced to less than 50 feet between the working edge of the excavation and any road or right-of-way, whichever is farther from the excavation, and provided that if the owner or operator installs visual screening and safety measures as required by the department.

A distance specified in this subsection is measured from the outside edge of the shoulder of the road or edge of the right-of- way unless otherwise specifically provided.

7. Property boundary. A natural buffer strip at least 50 feet wide must be maintained between any excavation and any property boundary. A natural buffer strip at least 25 feet wide must be maintained between any topsoil excavation and a property boundary. These distances may be reduced to not less than 10 feet with the written permission of the affected property owner or owners, except that the distance may not be reduced to less than 25 feet from the boundary of a cemetery or burial ground. The buffer strip between excavations owned by abutting owners may be eliminated with the abutter's written permission, provided the elimination of this buffer strip does not increase the runoff from either excavation across the property boundary. Any written permission to reduce a buffer must provide that it remains in effect until mining ceases and must be recorded in the registry of deeds. All property boundaries must be identified in the field by markings such as metal posts, stakes, flagging or blazed trees. The department may not grant a variance from the provisions of this subsection.

8. Erosion and sedimentation control. All reclaimed and unreclaimed areas, except for access roads, must be naturally