Code of 1986 is amended— (1) by striking 24-month period each place it appears in paragraphs (1) and (4) and inserting 7-year period , and (2) by striking paragraph (5). (b) Effective date The amendments made by this section shall apply to amounts paid or incurred after the date of the enactment of this Act. 513. Natural gas gathering lines treated as 15-year property (a) In general Subparagraph (E) of section 168(e)(3) of the Internal Revenue Code of 1986 is amended by striking and at the end of clause (viii), by striking the period at the end of clause (ix) and inserting , and , and by adding at the end the following new clause: (x) any natural gas gathering line the original use of which commences with the taxpayer after the date of the enactment of this clause. . (b) Alternative system The table contained in section 168(g)(3)(B) of the Internal Revenue Code of 1986 is amended by inserting after the item relating to subparagraph (E)(ix) the following new item: (E)(x) 22 . (c) Conforming amendment Clause (iv) of section 168(e)(3)(C) of the Internal Revenue Code of 1986 is amended by inserting and on or before the date of the enactment of subparagraph (E)(x) after April 11, 2005 . (d) Effective date (1) In general The amendments made by this section shall apply to property placed in service on and after the date of the enactment of this Act. (2) Exception The amendments made by this section shall not apply to any property with respect to which the taxpayer or a related party has entered into a binding contract for the construction thereof on or before the date of the enactment of this Act, or, in the case of self-constructed property, has started construction on or before such date. 514. Repeal of domestic manufacturing deduction for hard mineral mining (a) In general Subparagraph (B) of section 199(c)(4) of the Internal Revenue Code of 1986 is amended by striking or at the end of clause (ii), by striking the period at the end of clause (iii) and inserting , or , and by adding at the end the following new