Northern Mariana Islands Covenant Implementation Act

Northern Mariana Islands Covenant Implementation Act - Declares it is Congress' intention in enacting this legislation to: (1) ensure effective immigration control by extending the Immigration and Nationality Act, as amended, in full to the Commonwealth of the Northern Mariana Islands with special provisions allowing for the orderly phasing-out of the nonresident contract worker program, and the orderly phasing-in of Federal responsibilities over immigration to the Commonwealth; and (2) minimize, to the greatest extent possible, potential adverse effects such phase-out might have on the Commonwealth's economy.

(Sec. 2) Amends the Act approving the Covenant to Establish a Commonwealth of the Northern Mariana Islands in Political Union with the United States of America (the Covenant Act) to apply the Immigration and Nationality Act, as amended, to the Commonwealth over a ten-year transition period during which the Attorney General shall implement an immigration transition program for it.

Sets forth a statutory scheme for: (1) temporary alien workers; (2) immigrants; (3) adequate employment in Commonwealth's tourism industry after the transition period ends; (4) nonimmigrant investor visas; (5) lawful entry under Commonwealth immigration laws; and (6) entry into the Commonwealth under one-time grandfather provisions for certain long-term employees.

Directs the Secretaries of the Interior and of Labor to develop a technical assistance program to aid Commonwealth employers in securing employees from among U.S. labor, including lawfully admissible freely associated state citizen labor. Authorizes appropriations.

Authorizes the Attorney General and the Secretary of Labor to establish Immigration and Naturalization Service, Executive Office of Immigration Review, and Department of Labor operations in the Commonwealth.

Directs the President to report to specified congressional committees an evaluation of the overall effect of the transition program and the Immigration and Nationality Act upon the Commonwealth.

Prohibits the Commonwealth from permitting an increase in the total number of alien workers present there on the date of enactment of this Act. Authorizes appropriations.