Any project that receives Federal funding is required by the National Environmental Policy Act (NEPA) of 1970 to perform an alternatives analysis. This is to make sure the alternative selected is most advantageous when considering all potential environmental and social impacts. There are different tiers of evaluation depending on the size and scope of the project. Due to the size and scope of the Purple Line it required an Environmental Impact Statement (EIS) which has multiple stages including a draft (DEIS) which gets put out for public and formal agency review and then the final (FEIS), which is also published for public review. The final step is that the EIS gets approved by way of the Record of Decision (ROD). Before any Federal funding can be received, the ROD must be in place.

The Federal Transit Administration (FTA)’s Record of Decision (ROD) marks the end of a thorough and extensive process to identify and then avoid, minimize or mitigate possible impacts to communities, historic structures and natural resources such as parks, wetlands and streams. The ROD summarizes the purpose and need of the project, the alternatives considered, the comments received during the review period and responses to those comments, the factors that support the selection of the proposed alternative, and the commitments to be carried into further engineering and construction of the project.

The Final Environmental Impact Statement (FEIS) builds upon the Alternatives Analysis/Draft Environmental Impact Statement (AA/DEIS) completed in October 2008. The FEIS assesses the potential transportation and environmental impacts and benefits of the Purple Line Preferred Alternative and the No Build Alternative. The FEIS was prepared by FTA, in cooperation with MTA, in accordance with the National Environmental Policy Act of 1969 (NEPA). It includes a Draft Section 4(f) Evaluation, prepared in accordance with Section 4(f) of the U.S. Department of Transportation Act of 1966, as well as other applicable laws. The FEIS addresses comments on the AA/DEIS, guides decision-making, and meets the federal and state regulatory obligations of FTA and Maryland Department of Transportation Maryland Transit Administration (MDOT MTA).

Potential impacts of the alternatives under consideration are presented in the AA/DEIS along with information on their benefits and costs. This document also proposes ways to avoid or reduce the possible impacts that could result from the alternatives under consideration. In addition, the AA/DEIS estimates the capital and operating and maintenance costs, the ridership, and cost effectiveness of each alternative. The AA/DEIS for the Purple Line follows the relevant FTA’s guidelines.

The AA/DEIS was available for public review for 90 days from October 17, 2008 to January 14, 2009. During this time, the Maryland Department of Transportation Maryland Transit Administration (MDOT MTA) held a series of public meetings and accepted and recorded public comments on the document and the project. The State of Maryland considered the public comments in making the decision on which alternative it selected. The Preferred Alternative was selected by Governor O'Malley in August 2009.