New oil spill legislation pending before a congressional conference committee has been thefocus of much attention. An important provision of the bill would create a contingency planning requirement for tanker owners and onshore oil producing, refining and transportation facilities.

Both the House and Senate versions of the oil spill bills require that the owners and operators of tank vessels and facilities submit contingency plans for the prevention, containment and cleanup of oil spills.Current U.S. legal requirements for such plans are haphazard. The Senate version of the new law would impose a deadline of as little as one year after enactment of the Oil Pollution Act for executive department implementation of the plans.

Among the proposals of the contingency plan requirement are:

* A description of the method of response to a "worst-case oil spill" in adverse weather conditions from the largest vessel known to transit the area covered by the plan.

* Identification of personnel and equipment, by contracts with cleanup companies or otherwise, to remove the spill promptly and mitigate damage to the environment.

* Procedures for early detection of oil spills and notification of national and regional strike forces. Although not specifically set forth in the bills, such procedures could include special watches, vessel patrols and fixed-wing aircraft or helicopter overflights to detect spills.

* Inventory of oil spill containment equipment. This information would include the number, types, operational capacity and availability of the equipment to implement the plan.

* Programs for personnel training (including surprise drills). The new law would also require a periodic inspection by owners as well as the government of containment booms, skimmers, vessels and other major equipment used to remove oil.

* Description of the means, such as use of dispersants, to be employed by vessel crews to contain and clean up the spilled oil, and to protect and mitigate the damages to the environment, including fish and other marine life.

* Arrangements for pre-positioning of oil spill containment and cleanup equipment and trained personnel at strategic locations from which they can be deployed promptly to the spill site.

* Procedures for safe disposal of any oil or hazardous materials recovered. Such procedures would, of course, have to consider the requirements of federal, state and local law.

In addition, vessel and facility operators would have to provide a detailed description of how the plan will be coordinated with the national contingency plan, regional and local plans and response efforts.

This requirement means that vessel and facility operators will have to familiarize themselves with the many phases of contingency planning above the private industry level and coordinate their efforts with federal, state and local governments.

After submission and approval, the provisions of the plans would be legally binding on vessel and terminal operators, and the federal courts would have jurisdiction to restrain violations of the plans or compel the owners and operators to implement the plans.

The provisions of the bills that would significantly raise the limits of liability of vessel owners and operators and shippers of bulk oil cargoes have elicited much attention. But the new legislation also mandates sweeping changes in prevention and removal measures.

The new law may require tank vessels operating on U.S. navigable waters to carry appropriate removal equipment employing the best technology that is ''economically feasible." Among the most widely publicized proposals is the requirement that tank vessels be fitted with double hulls and double bottoms.

In order for vessels to operate in U.S. waters, the plans will have to be approved by the government to ensure that they are adequate to contain and remove oil spills and give sufficient consideration to such factors as the amount of vessel traffic in the area, the value and sensitivity of surrounding wildlife and other natural resources and the history of prior oil spills.

The proposed legislation makes it clear that in the future high priority will be given to requirements for detailed, carefully thought out and realistic advance planning for oil spills.