The Attorney General shall arrange for appropriate places of detention for aliens detained pending removal or a decision on removal. When United States Government facilities are unavailable or facilities adapted or suitably located for detention are unavailable for rental, the Attorney General may expend from the appropriation “Immigration and Naturalization Service—Salaries and Expenses”, without regard to section
6101 of title
41, amounts necessary to acquire land and to acquire, build, remodel, repair, and operate facilities (including living quarters for immigration officers if not otherwise available) necessary for detention.