To reauthorize the Generalized System of Preferences, and for other purposes.

Amends the Trade Act of 1974 to extend duty-free treatment under the Generalized System of Preferences through June 30, 2000. (Sec. 1) Provides, upon request filed with the Customs Service, for the liquidation or reliquidation (refund of duties) on entries of articles to which duty-free treatment under the Generalized System of Preferences would have applied if it had been in effect between June 30, 1998, and the date of enactment of this Act. (Sec. 2) Amends the Tariff Act of 1930 to allow a duty drawback (refund of duty) for methyl tertiary-butyl ether (MTBE), a finished petroleum derivative, provided certain requirements are met. (Sec. 3) Revises the methodology used to calculate the refund of duties on the export of finished petroleum derivatives that have been manufactured with (and substituted for) a qualified article which is of the same kind and quality (whether imported duty-paid or domestic). Redefines the term "qualified article" to include certain manufactured articles (primary forms), including articles of the same kind and quality, or any combination thereof, that are transferred as certified in a certificate of delivery or certificate of manufacture and delivery to an exporter in a quantity not greater than the quantity of articles purchased or exchanged for use in the manufactured article. (Sec. 4) Directs the Secretary of the Treasury, upon proper request, to reliquidate as free of duty certain entries of: (1) nuclear fuel assemblies; and (2) water resistant wool trousers. Requires a refund of any duties paid with respect to such entries. (Sec. 6) Directs the U.S. Customs Service, upon proper request, to: (1) liquidate or reliquidate as if the special column one duty rate applicable for Canada applied to certain entries or withdrawals for warehouse of mueslix cereal during 1992 through 1995; and (2) refund to the importer any excess duties paid with respect to such entries. (Sec. 7) Directs the Foreign Trade Zones Board to expand Foreign Trade Zone No. 143 to include areas in the vicinity of the Chico Municipal Airport in accordance with the application submitted to the Board by the Sacramento-Yolo Port District of Sacramento, California, on March 11, 1997. (Sec. 8) Amends the Consolidated Omnibus Budget Reconciliation Act of 1985 to provide for the use of customs user fees, to the extent funds remain available after making certain reimbursements, for salaries for up to 50 full-time equivalent inspectional positions to provide preclearance services. Provides for the collection of a $1 customs user fee from each passenger aboard a commercial vessel whose arrival: (1) originated in Canada, Mexico, a U.S. territory or possession, or any adjacent island; or (2) originated in the United States and was limited to such places. (Currently, such fees are prohibited.) Earmarks, subject to appropriations Acts, a specified amount of certain customs user fees for the Customs Service for automated commercial systems. Directs the Commissioner of Customs to establish an advisory committee, consisting of representatives from the airline, cruise ship, and other transportation industries, to advise the Commissioner on issues related to the performance of the inspectional services of the U.S. Customs Service. (Sec. 9) Amends the Tariff Act of 1930 to exempt certain woven fabrics containing silk or silk waste from the country of origin marking requirements under such Act.