OPA-90 — US Oil Pollution Act 1990

The Oil Pollution Act of 1990 (33 USC §2701 et seq.) was enacted by the United States Congress in the immediate aftermath of the Exxon Valdez disaster of 24 March 1989. OPA-90 replaced a fragmented patchwork of federal liability statutes — the Federal Water Pollution Control Act, the Deepwater Port Act, the Outer Continental Shelf Lands Act, and others — with a single, comprehensive framework imposing strict liability for oil pollution in US navigable waters, the contiguous zone, and the exclusive economic zone (EEZ). The regime is administered jointly by the US Coast Guard (USCG), the Environmental Protection Agency (EPA), the Pipeline and Hazardous Materials Safety Administration (PHMSA), and the National Pollution Funds Center (NPFC).

OPA-90 is significantly stricter than MARPOL Annex I and is explicitly not pre-empted by MARPOL or any other international convention — Congress made clear that state and federal law supplement rather than yield to international obligations. Every vessel trading to a US port, offshore terminal, or operating in the EEZ must understand OPA-90's requirements as a distinct compliance layer on top of MARPOL.

Vessel Response Plan (VRP)

A Vessel Response Plan is mandatory for:

· Tank vessels ≥ 400 GT carrying oil in bulk as cargo.
· Non-tank vessels ≥ 400 GT using oil as fuel (bunker vessels).
· Offshore facilities and certain mobile offshore drilling units (MODUs).

The VRP must be submitted to and approved by the USCG (via the NVMC — National Vessel Movement Center) and renewed every five years or following any material change in vessel structure, equipment, or operating area. The plan must address three discharge scenarios:

Average Most Probable Discharge (AMPD) — the typical small operational spill (e.g., a hose coupling failure during cargo transfer). VRP must demonstrate response capability within 1 hour.
Maximum Most Probable Discharge (MMPD) — a larger but credible accident scenario. VRP must address response within 6 hours.
Worst Case Discharge (WCD) — the total loss of the vessel's largest cargo tank(s) or bunker capacity. VRP must specify full OSRO mobilisation, skimmer deployment, and shoreline protection strategies. The WCD scenario governs OSRO contract sizing.

OSRO contracts

Vessels subject to VRP requirements must have pre-existing contracts with USCG-classified Oil Spill Removal Organisations (OSROs) capable of responding to the WCD scenario in each USCG Captain of the Port (COTP) zone in which the vessel operates. The USCG classifies OSROs by geographic zone and by response capability tier (Tier 1 through Tier 4 for open-water response; shore and inland classifications separately).

Major OSRO providers include Marine Spill Response Corporation (MSRC), Clean Caribbean Cooperative (CCC), O'Brien's Response Management, and various regional cooperatives. Annual drills and tabletop exercises are required to validate response capability; unannounced USCG exercises are conducted periodically and results affect VRP approval status.

Certificate of Financial Responsibility (COFR)

Every vessel over 300 GT that uses the navigable waters of the United States, or that operates in the EEZ to transship or lighter oil, must carry a valid COFR issued by the USCG. The COFR evidences the vessel's ability to pay for oil spill clean-up costs and natural resource damages up to the applicable OPA-90 liability limit. Limits (as of the most recent USCG adjustment) are broadly:

Single-hull tank vessels — $3,200 per gross ton, with a minimum of $6m and a maximum that can exceed $80m for a VLCC.
Double-hull tank vessels — $1,900 per gross ton (lower limit recognises reduced risk). Periodically adjusted by USCG rulemaking.
Non-tank vessels — $1,000 per gross ton, minimum $950,000.

A COFR is typically backed by a letter of undertaking from a P&I Club, a surety bond from a USCG-approved surety, or by the vessel owner's own evidence of financial resources. Operating in US waters without a valid COFR is a strict-liability civil penalty offence and will result in vessel detention.

Liability framework

OPA-90 imposes strict liability — that is, liability without the need to prove negligence — on the "responsible party" (owner, operator, or demise charterer) for all removal costs and damages resulting from a discharge of oil into US waters. Recoverable damages include: removal costs, natural resource damages (assessed by federal and state trustees), real and personal property damage, lost profits and earning capacity, loss of subsistence use of natural resources, and government revenue loss. The liability limits described above cap the responsible party's exposure — but the limits are removed entirely in cases of:

· Gross negligence or wilful misconduct.
· Violation of a federal safety, construction, or operating regulation.
· Failure to report the discharge.
· Failure to co-operate and provide reasonable care after the discharge.

The Oil Spill Liability Trust Fund (OSLTF), administered by the NPFC, can advance up to $1bn per incident when the responsible party is unknown, cannot pay, or when damages exceed the limit. The Fund then seeks recovery from the responsible party by subrogation.

Tank vessel construction requirements

OPA-90 mandated a phased elimination of single-hull tank vessels from US waters, completed by 2015 (with limited exceptions for smaller vessels). All tank vessels now trading in US waters must be double-hulled (or equivalent protective location per MARPOL Regulation 19). Annual structural inspections by the USCG complement flag-state and classification surveys. OPA-90 also requires operators of tank vessels >250 bbls capacity to submit a Spill Mitigation Procedures document as part of the VRP, detailing measures to minimise spill volume in the event of a grounding or collision.

Drug and alcohol testing

OPA-90 directed USCG to establish mandatory drug and alcohol testing for crew members involved in any marine casualty — serious marine incident (SMI) testing (46 CFR Part 4). Testing applies to the person in charge of the vessel and any crew member directly involved in a casualty. Breath and urine testing must occur within two hours of the casualty wherever practicable. Results form part of the marine casualty investigation. Pre-employment, random, periodic, post-incident, and reasonable-cause testing programmes are all required under 46 CFR Part 16 for commercial vessels subject to manning requirements.

State law co-existence

Unlike many federal environmental statutes, OPA-90 expressly preserves state law — Section 1018 provides that nothing in OPA-90 pre-empts any state from imposing additional liability or requirements with respect to the discharge of oil or a substantial threat of discharge. Several states have enacted supplementary regimes:

California — California Lempert-Keene-Seastrand Oil Spill Prevention and Response Act (OSPRA); stricter financial responsibility, mandatory spill response advisors for tank vessels, state-level OSRO classification.
Washington — Oil Spill Prevention Act; requires dedicated financial assurance above OPA-90 minimums for Puget Sound and coastal operations.
Alaska — Terminal operations and tanker regulations; mandatory pilotage, tug escorts, and enhanced contingency plans in Prince William Sound and Cook Inlet.

Practical onboard requirements

Declaration of Inspection (DOI) — required before each cargo transfer operation. Both the vessel representative and the shore facility must sign the DOI confirming that all pre-transfer checks (hoses, valves, communications, overflow alarms) have been completed.
Person in Charge (PIC) qualification — the master or officer in charge of a cargo transfer must hold a valid PIC designation under 33 CFR Part 156. PIC qualification is separate from STCW certification and requires specific training and examination.
Spill reporting — National Response Center (NRC) — any discharge of oil into US navigable waters, regardless of quantity, must be reported to the NRC (telephone 1-800-424-8802) as soon as the responsible party has knowledge. Failure to report within 24 hours is an independent criminal offence. MARPOL SOPEP notification procedures do not substitute for NRC reporting.
SOPEP supplementation — vessels trading to US waters typically maintain a Shipboard Oil Pollution Emergency Plan (SOPEP) under MARPOL Annex I alongside an OPA-90 VRP. The VRP references and incorporates the SOPEP but contains US-specific notification trees, OSRO contact details, and WCD calculations not found in a standard SOPEP.

Notable enforcement cases

Exxon Valdez1989 (catalyst)
The grounding in Prince William Sound, Alaska — 11 million gallons of crude oil — directly prompted Congress to enact OPA-90. The subsequent civil and criminal litigation established benchmark figures for natural resource damages and demonstrated the inadequacy of the pre-OPA liability regime.
Cosco Busan2007
Container vessel struck the San Francisco Bay Bridge in fog, spilling approximately 53,000 gallons of bunker fuel. The pilot and operator were both prosecuted; the operator's captain-of-the-port suspension and the pilot's criminal conviction highlighted OPA-90's extension of liability beyond the vessel owner.
DBL 1522005
Dumb barge in the Houston Ship Channel; a single-hull design that experienced structural failure during cargo transfer. The case reinforced the double-hull phase-out schedule and the importance of structural surveys on aged tank barges operating in US waters.

Industry compliance practice

Shipowners and operators with significant US trade maintain dedicated OPA-90 compliance packages separate from their standard ISM documentation. These typically include: a current COFR for each vessel (with renewal tracked 90 days in advance), executed OSRO contracts with proof of exercise completion, vessel-specific VRPs lodged with the NVMC, PIQ-qualified officer lists, and standing arrangements with US maritime attorneys for casualty response. P&I Clubs provide OPA-90 letters of undertaking as standard for members on US trades, and most club correspondents in major US ports have OPA-90 response checklists for the first 24 hours following any incident.