FOR nearly a decade, the United States government's interest in the so-called Law of the Sea Treaty lay bottomed on the ocean floor. But US diplomatic salvagers are raising the treaty out of the depths and toward acceptance.
The US may sign the pact - which it spurned in 1982 - as early as this summer. It could be many months before the treaty (formally the United Nations Convention on the Law of the Sea) is ratified by the Senate, however.
US-led efforts to update and recodify international rules and customs governing maritime shipping, navigation, rights of passage, fishing, and the like culminated in 1982 when the Third UN Conference on the Law of the Sea adopted the agreement. But the Reagan administration repudiated the treaty, owing to the regulation of deep-seabed mining contained in Part XI.
At issue were what some people depicted to be an El Dorado of mineral wealth in the seas' inky troughs - especially softball-sized nodules, rich in manganese, nickel, and other metals, that litter parts of the ocean floor. Although the economical recovery of these minerals is decades in the future, developing countries were determined to share in the wealth if commercial mining eventually becomes feasible.
The UN conferees established in Part XI a cumbersome structure for regulating deep-seabed mining. Worse, in the eyes of critics, Part XI obligated the major mining nations to share technology and mineral claims with a UN-controlled competitor.
Free-market conservatives in the US, Britain, and Germany denounced the Part XI regimen as seabed socialism, and their governments refused to sign the pact.
Washington's interest began to flicker again about 1990, however, for several reasons:
* Despite concerns about Part XI, ``people saw that 90 percent of the convention was useful and necessary,'' says James Lawless, an official in the Commerce Department's National Oceanic and Atmospheric Administration.
``For both security and commercial reasons, the United States has a big interest in stability of the law of the sea,'' says Louis Henkin, a professor of international law at Columbia University. ``That law is intrinsically unstable without a treaty.''
* Heightened attention to the global environment spurred interest in the sea treaty's environmental provisions. ``Many people recognized that in the Law of the Sea Treaty, we already had the most comprehensive international environmental treaty in existence,'' says Daniel Nyhart, a professor at the Massachusetts Institute of Technology.
* In the 1980s, some countries asserted aggressive new ocean rights. ``We saw a tremendous growth in unilateral claims by coastal nations on international seas,'' says James Broadus, director of the Marine Policy Center at the Woods Hole Oceanographic Institute in Woods Hole, Mass.
* Clearly the convention was going to enter into effect, with or without the US, as many small countries proceeded to ratify it. The treaty will become effective Nov. 16, after Guyana's approval last fall achieved the required 60-nation ratification threshold. While nonsignatories will not be bound by the pact, some Americans were uneasy at the prospect of the US's remaining aloof.
* Finally, many developing countries were willing to modify the provisions on deep-seabed mining. ``The Part XI provisions were pushed during the heyday of third-world interest in global wealth transfers, the `New International Economic Order,' the OPEC cartel, and so on,'' says a State Department official who asked not be named. ``The developing countries finally realized they had created a nonstarter.''
Since last spring US negotiators at the UN have been working to resolve disputes over Part XI. In the view of many participants and outside observers, the deep-seabed-mining regulations have been rendered effectively toothless.
Some US mining executives remain unappeased, however. Last month mining-industry representatives testified before a House of Representatives subcommittee against the revised treaty, contending that Part XI still created regulatory uncertainty that would deter future investors.
Some conservative pundits continue to denounce the treaty as inimical to free enterprise.
Many experts say Part XI has received far too much attention, however. ``The notion of immense riches under the sea is rather a phantom,'' Mr. Broadus says. ``The nodules are not an economically important resource. The significant stakes in the Law of the Sea Treaty are all the other ocean uses it covers.''