It is recognised that it may be desirable to mine and remove coal to ensure long-term site safety, or facilitate remediation or environmental protection.
Cydnabyddir y gallai fod yn ddymunol cloddio am lo a symud glo i sicrhau diogelwch hirdymor y safle, neu i hwyluso’r gwaith adfer neu i warchod yr amgylchedd.