Unless otherwise determined by the Secretary, each well drilled pursuant to the terms of the lease may be drilled or slant drilled to and into the subsurface of the tide or submerged lands covered by the lease from upland or littoral drill sites owned or controlled by the State or owned by or available to the lessee, or from drill sites located upon any lands filled before or after July 1, 1966, whether contiguous or noncontiguous to the littoral lands or uplands, or from any pier constructed before or after July 1, 1966, owned by or available to the lessee and available for such purpose, or from platforms or other fixed or floating fixtures in, on or over the submerged lands covered by the lease, or otherwise available to the lessee.