Section 4110.4-2 - Decrease in land acreage(a) Where there is a decrease in public land acreage available for livestock grazing within an allotment:(1) Grazing permits or leases may be cancelled or modified as appropriate to reflect the changed area of use.(2) Grazing preference may be canceled in whole or in part. Cancellations determined by the authorized officer to be necessary to protect the public lands will be apportioned by the authorized officer based upon the level of available forage and the magnitude of the change in public land acreage available, or as agreed to among the authorized users and the authorized officer.(b) When public lands are disposed of or devoted to a public purpose which precludes livestock grazing, the permittees and lessees shall be given 2 years' prior notification except in cases of emergency (national defense requirements in time of war, natural disasters, national emergency needs, etc.) before their grazing permit or grazing lease and grazing preference may be canceled. A permittee or lessee may unconditionally waive the 2-year prior notification. Such a waiver shall not prejudice the permittee's or lessee's right to reasonable compensation for, but not to exceed the fair market value of his or her interest in authorized permanent range improvements located on these public lands (see § 4120.3-6 ).43 FR 29067, July 5, 1978, as amended at 49 FR 6451, Feb. 21, 1984; 49 FR 12704, Mar. 30, 1984; 54 FR 31485, July 28, 1989; 60 FR 9963, Feb. 22, 1995; 71 FR 39505 , July 12, 2006