Public comments recently submitted to Maryland transportation officials about a Purple Line’s potential impact focused on concerns about the proposed light-rail line’s noise, vibrations and destruction of trees and wildlife.

The deadline to submit comments about the state’s final study of a 16-mile Purple Line’s potential environmental and community impact was Monday, but state officials said Wednesday that they did not have a final tally.

The comments included neighborhood groups who said the Maryland Transit Administration’s analysis did not adequately assess the noise, vibrations and loss of tree canopy that light-rail trains would bring to communities between Bethesda and New Carrollton.

Environmental activists said the state analysis missed the potential impact on an endangered species in Rock Creek Park. Trail advocates said it did not adequately address potential health impacts on people who use the Georgetown Branch trail between Bethesda and Silver Spring, where acres of mature trees would be cut to accommodate trains.

Casa de Maryland, an advocacy group for low-income Latinos, voiced concerns about residents and businesses being displaced from the internationally diverse Langley Park area. The study, the group said, did not adequately address impacts to “environmental justice populations,” primarily low-income and minority residents.

Map of the proposed Purple Line

The organization said it submitted a petition signed by 350 people asking for written documentation of how the state plans to prevent residents and businesses from being priced out of the area due to rents rising along with economic development around train stations.

The group also submitted a letter signed by 22 neighborhood organizations asking the state to create job training and placement programs to ensure local residents benefit from Purple Line construction jobs and those created by economic development.

Zorayda Moreira-Smith, the group’s manager of housing and community development, said Casa de Maryland supports a Purple Line for the area’s highly transit-dependent residents, but it wants the state to show how it would protect affordable housing and local jobs.

Without such planning, Moreira-Smith said in an interview, “The folks who would really benefit from it and who most need it would be displaced eventually and wouldn’t be able to benefit from it.”

The state’s analysis said the transit agency “understands small, local and [environmental justice] businesses will require some unique engagement.” It said the state will have a “business impact mitigation plan” to help local businesses during construction and will work with local officials on job development programs and affordable housing.

Maryland transit officials have said they plan to submit the final impact study to the Federal Transit Administration later this fall. If the federal agency approves it in a “record of decision,” state officials have said they plan to begin condemning private property to buy for the line’s right-of-way.

Paul Shepard, a spokesman for the Maryland Transit Administration, declined to respond to any points made in the public comments.

“We appreciate the comments we received,” Shepard said in an e-mailed statement. “We will review each in detail. Responses will be part of the Record of Decision, which will also document our mitigation commitments. We can’t yet respond to any specific comments until we have a chance to read and analyze them.”

State officials have said they hope to begin construction of the line in mid-2015 and open it in mid-2020. The state is seeking $900 million in federal funding and private investors to help build the $2.2 billion project.

The line would connect communities between Bethesda and New Carrollton — including Silver Spring, Langley Park, College Park and Riverdale Park — and link them to Metrorail, Amtrak and MARC commuter rail stations. State transit planners say two-car trains running along local streets, mostly in their own lanes, would be faster and more reliable than buses stuck in traffic and would reinvigorate older suburbs with new development around stations.

Leaders for the Town of Chevy Chase said state planners should redo the analysis and look again at other options, such as a less expensive busway, because the estimated construction costs of a light-rail line have “skyrocketed” from about $1 billion in 2007 to $2.2 billion. The final analysis also did not include all of the project’s design details, leaving the public unable to assess their potential impacts, town officials wrote.

John Fitzgerald, an environmental lawyer who lives in Chevy Chase near the proposed light-rail alignment, said the study left out an endangered species, the Hay’s Spring amphipod, which would be affected by a Purple Line’s construction and operations. The small, colorless crustacean is found in Rock Creek Park, downstream of the proposed alignment. Fitzgerald said the amphipod turns leaves into nutrients for other species. He said Rock Creek is the only known habitat for the Hay’s Spring amphipod.

Fitzgerald, who previously worked for environmental groups, said the state must consult with the U.S. Fish and Wildlife Service to assess the potential impacts to the crustacean, as well as ways those impacts could be reduced.

The state’s study found “no long-term impacts on known rare, threatened or endangered species,” according to the executive summary.

Fitzgerald said he and other environmental activists are considering a lawsuit to prevent any rail line construction until the endangered species issue is addressed.

Advocates for the Georgetown Branch extension of the Capital Crescent Trail said a light-rail line would “irrevocably destroy” the rare parkland in an otherwise densely developed area. The state also has not fully informed the public about other “reasonable alternatives” that could avoid or minimize such impacts, including a busway, said the Friends of the Capital Crescent Trail.