A site plan for rehabilitation, showing both existing and proposed final contours, shall be submitted. After any such operations, the site shall be made reusable for a use permitted in the zoning district. Where topsoil is removed, sufficient arable soil shall be set aside for retention on the premises and shall be respread over the premises after the operation is terminated. Except where lakes are created and retained, the area shall be brought to final grade by a layer of earth at least two feet deep or to original thickness, whichever is less, and capable of supporting vegetation or shall meet those requirements established by the DEP. Fill shall be of material acceptable to the DEP. Where deemed necessary by the Borough Council, the applicant shall be required to post a bond sufficient to cover the costs of reclamation.