Authorizes the Administrator to provide for an alternative mechanism of compliance for a marine vessel if: (1) the vessel employs a control technology that reduces emissions of sulfur oxides and particulate matter to at least the same degree as the reduction that would be achieved through compliance with the applicable fuel sulfur content limitation; and (2) the emission reductions achieved are in addition to any reductions required to achieve compliance with an applicable engine emission standard.

Requires: (1) the Administrator, no later than December 15, 2008, to establish and periodically revise standards for emissions of oxides of nitrogen, particulate matter, hydrocarbons, and carbon monoxide from newly-manufactured and in-use main and auxiliary engines in oceangoing marine vessels that enter or leave a U.S. port or offshore terminal; and (2) such standards to require, beginning January 1, 2012, that the engines achieve the greatest degree of emission reduction achievable through the application of available technology.

Directs the Administrator, upon determining that the maximum level of control required by regulations applicable to on-road, nonroad, and stationary engines or achieved by sources from which control technologies may be transferred, including sources that use advanced aftertreatment technologies, will not be technically achievable by January 1, 2012, to promulgate: (1) standards that require the level of control that will be technically achievable by that date; and (2) additional standards that require either such maximum level of control or the level that will be technically achievable beginning January 1, 2016.