(a) Upon termination of lease, permanent improvements, unless otherwise provided by written agreement with the surface owner and filed with the Superintendent, shall remain a part of said land and become the property of the surface owner upon termination of the lease, other than by cancellation. Exceptions include personal property not limited to tools, tanks, pipelines, pumping and drilling equipment, derricks, engines, machinery, tubing, and the casings of all wells: Provided, That when any lease terminates, all such personal property shall be removed the word “terminates”; and in the last sentence of the paragraph, within 90 days or such reasonable extension of time as may be granted by the Superintendent. Otherwise, the ownership of all casings shall revert to Lessor and all other personal property and permanent improvements to the surface owner. Nothing herein shall be construed to relieve lessee of responsibility for removing any such personal property or permanent improvements from the premises if required by the Superintendent and restoring the premises as nearly as practicable to the original state.

(b) Upon cancellation of lease. When there has been a cancellation for cause, Lessor shall be entitled and authorized to take immediate possession of the lease premises and all permanent improvements and all other equipment necessary for the operation of the lease.

(c) Wells to be abandoned shall be promptly plugged as prescribed by the Superintendent. Applications to plug shall include a statement affirming compliance with §226.28(b) and shall set forth reasons for plugging, a detailed statement of the proposed work including kind, location, and length of plugs (by depth), plans for mudding and cementing, testing, parting and removing casing, and any other pertinent information: Provided, That the Superintendent may give oral permission and instructions pending receipt of a written application to plug a newly drilled hole. Lessee shall remit a fee of $15 with each written application for authority to plug a well. This fee will be refunded if permission is not granted.

(d) Lessee shall plug and fill all dry or abandoned wells in a manner to confine the fluid in each formation bearing fresh water, oil, gas, salt water, and other minerals, and to protect it against invasion of fluids from other sources. Mud-laden fluid, cement, and other plugs shall be used to fill the hole from bottom to top: Provided, That if a satisfactory agreement is reached between Lessee and the surface owner, subject to the approval of the Superintendent, Lessee may condition the well for use as a fresh water well and shall so indicate on the plugging record. The manner in which plugging material shall be introduced and the type of material so used shall be subject to the approval of the Superintendent. Within 10 days after plugging, Lessee shall file with the Superintendent a complete report of the plugging of each well. When any well is plugged and abandoned, Lessee shall, within 90 days, clean up the premises around such well to the satisfaction of the Superintendent.