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national air carrier
An airline with annual revenues of between $100 million and $1 billion.
National Environmental Policy Act (NEPA)
Federal law providing for environmental assessments of impacts and public input into all federally funded projects; an environmental study could be either an environmental impact statement or environmental assessment.
National Highway System (NHS)
An approximately 155,000-mile, still-to-be-designated network, to provide an interconnected system of principal routes to serve major travel destinations and population centers; picks up where the Interstate Highway System left off.
no-build alternative (also known as “no-action alternative”)
Option of maintaining the status quo by not building transportation improvements; serves as a baseline for comparison of “build” alternatives.
North American Free Trade Agreement (NAFTA)
A formal agreement, or treaty, between Canada, Mexico and the United States of America to promote means for improved and increased free trade between the three countries; the effect of NAFTA on transportation was to increase the need to upgrade existing, and build new, transportation facilities between and within the countries.
no turn on red (NTOR)
This message on signs is used to indicate that a right turn on red (or left turn on red for one-way streets) is not permitted at an intersection.
notice of intent (NOI)
A notice that is prepared to inform the public that an environmental impact statement will be prepared for a project.
nonattainment area
A metropolitan area that has failed to meet national ambient air quality standards.