By John S. McClenahen No one knows for sure whether U.S. West Coast ports will close again if current labor-management contract negotiations fail and an 80-day "cooling-off" period under the Taft-Hartley Act expires. But manufacturers and other U.S. shippers are making contingency plans. The most likely moves, according to a survey done by BDP International, a Philadelphia logistics and transportation services company, include cargo diversions to East Coast ports, increases in safety stocks, alternate sourcing and diversions to Gulf Coast ports. However, some U.S. manufacturers apparently were not hurt by the first shutdown of West Coast ports at the end of September. BDP International quotes one U.S. manufacturer as claiming that fewer "dumped" foreign goods produced "orders from many companies looking for a domestic alternate source."