(2) The size and shape of spacing units shall be such as will result in efficient and economical development of the pool or field as a whole and the size thereof may not be smaller than the maximum area that can be efficiently drained by one well.

(3) An order establishing spacing units for a pool or field shall specify the size and shape of each unit and the location of each permitted well thereon in accordance with a reasonably uniform spacing plan. If an owner finds that a well drilled at the prescribed location would not produce in paying quantities or that surface conditions would substantially add to the burden or hazard of drilling such well, then the owner may apply to the department for permission to drill a well at a location other than that prescribed by such spacing order. The department shall notify adjacent mineral owners of such application and any such owner may request a hearing by the board to consider the application. If no request for a hearing is made in writing within 20 days, the department may issue an order approving the drilling site. Any order by the board or department under this section shall include in the order suitable provisions to prevent the production from the spacing unit of more than its just and equitable share of the oil and gas in the pool.

(4) An order establishing spacing units for a pool or field shall cover all lands determined or believed to be underlaid by such pool or field and may be modified by the board from time to time to include additional areas determined to be underlaid by such pool or field. When necessary to prevent waste of oil or gas, to protect correlative rights or to provide for more efficient drainage, an order establishing spacing units in a pool or field may be modified by the board to increase the size of spacing units for future wells in a pool or field or any zone thereof or to permit the drilling of additional wells on a reasonably uniform plan in such pool, field or zone. [Formerly 520.065; 1981 c.146 §4; 2007 c.672 §18]