Tex. Natural Resources Code § 101.016

(a) An agreement authorized by this chapter may provide for the location and spacing of input wells and for the extension of leases covering any part of land committed to the unit as long as operations for drilling or reworking are conducted on the unit or as long as production of oil or gas in paying quantities is had from any part of the land or leases committed to the unit. However, no agreement may relieve an operator from the obligation to develop reasonably the land and leases as a whole committed to the unit.

(b) An agreement authorized by this chapter may provide that the dry gas after extraction of hydrocarbons may be returned to a formation underlying any land or leases committed to the agreement and may provide that no royalties are required to be paid on the gas so returned.