Sec. 501. (a) Military construction for the Safeguard anti-ballistic missile system is authorized for the Department of the Army as follows: Military family housing, Grand Forks Safeguard site, North Dakota, two hundred and eighteen units, $6,004,000. (b) Authorization contained in this section shall be subject to the authorizations and limitations of the Military Construction Authorization Act, 1973, in the same manner as if such authorizations had teen included in that Act.