Offshore oil and gas facilities must be periodically inspected and maintained to assure structural integrity and minimize pollution and safety risks. This involves periodic surface preparation and coating activities. In U.S. waters, the United States Coast Guard (USCG) prohibits the discharge of garbage from any fixed or floating platform (33 Code of Federal Regulations 151.73), including discharges related to maintenance activities. In 2007, the American Petroleum Institute prepared Bulletin 91 Planning and Conducting Surface Preparations and Coating Operations for Oil and Natural Gas Drilling and Production Facilities in the Marine Environment to meet the intent of MARPOL 73/78 (International Convention for the Prevention of Pollution from Ships), specifically Annex V, which regulates the discharge of garbage. USCG has specifically requested, however, that industry develop performance-based practices and quantifiable measurements for discharges related to surface preparation and coating activities.
In late 2007, offshore companies began using a Best Management Practices plan template that allows companies to establish—within a consistent framework—practices and procedures to minimize the discharge of spent abrasives and paint overspray to the surrounding waters to the maximum extent practicable. Plans that are developed based on this template meet the requirements of the U.S. Environmental Protection Agency Region 6 National Pollutant Discharge Elimination System Offshore general permit.
In May 2008, the Offshore Operators Committee hosted a workshop to better understand current practices conducted on offshore facilities. The workshop was the first step of a "due diligence" process to ensure that USCG concerns do not adversely affect ongoing operations in the Gulf of Mexico. Subsequent steps will build upon this by obtaining information about abrasives and coatings currently being used by industry and then developing a recommended practice to prevent their discharges into surrounding waters to the maximum extent practicable.
This paper describes the development of practices at Shell that are intended to meet the intent of MARPOL from a regulatory and industry standpoint. It provides information on surface preparation methods and coating types that have been used to reduce discharges, emissions, and wastes, as well as reduce costs and enhance the safety of offshore workers.
Over the past 10 years, significant changes have occurred in surface preparation methods and corrosion protection systems for oil and gas facilities in the marine environment. Increasingly stricter regulatory initiatives also mean that the offshore industry needs to continually evaluate its methodologies and procedures that can reduce safety and environmental effects of its activities. The harsh conditions of the marine environment require that operators diligently safeguard the integrity of their facilities, which are typically expected to have a service life of 20-plus years. As new and larger facilities expand into increasingly deeper waters, the distance from shore increases the related maintenance and transportation costs.