A bill to amend the Regional Rail Reorganization Act of 1973 with respect to the light density lines which are not designated by the U.S. Railway Association to be operated in the final system plan.

Defines "interim light density lines" for purposes of the Regional Rail Reorganization Act as meaning all rail properties used or useful in providing local rail service, except rail properties designated as profitable lines or approved for abandonment.

Authorizes an additional appropriation of $5,000,000 to the Interstate Commerce Commission for use by the Rail Services Planning Office in carrying out its functions pursuant to such Act. Increases from $26,000,000 to $50,000,000 the appropriation to the United States Railway Association for administrative expenses.

Directs the Association and the Office, following the effective date of the final system plan, to begin a further study of interim light density lines, including (1) analysis of the methodology used to determine the economic viability of light density lines, (2) analysis of subsidy standards and suitability criteria developed by the Office prior to issuance of the final system plan, and (3) development of an accounting system to determine the revenue, costs, and operations of light density lines as economic units.

Requires the Association to issue a final report within 270 days of the effective date of the final system plan on the methodology to be used to determine the economic viability of interim light density lines, and submit copies of such report to the Senate Committee on Commerce and the House Committee on Interstate and Foreign Commerce.

Sets forth deadlines and requirements for further reports by the Association reviewing and reevaluating the economic viability of interim light density lines.

Permits rail service on light density lines operated by the Corporation or any profitable railroad pursuant to this Act to be discontinued, to the extent such discontinuance is not precluded by the terms of leases and agreements, if (1) the final report of the Association made pursuant to this Act does not designate rail service to be operated over such lines; and (2) 60-day notice is provided to involved parties. Sets forth requirements governing abandonment of such lines.

States that the Federal share of rail continuation subsidies for interim light density lines shall be 100 percent.

Requires recipients of rail continuation subsidies to implement the accounting and information system developed by the Association pursuant to this Act.