Advocates are urging federal regulators to consider the full environmental costs of a floating liquified natural gas terminal 12 miles off the Texas coast.

The Maritime Administration is accepting public comments until June 1 on a draft environmental impact statement for the ST LNG Export Terminal planned offshore in East Matagorda Bay, southwest of Houston.

The terminal would be built in four phases and designed to process up to 8.4 million metric tons of LNG per year at full capacity. The offshore terminal would be connected to a new 5.5-mile-long natural gas pipeline, which would be supplied by gas originating from the Tres Palacios Natural Gas Storage and Trading Hub and the Williams Markham Gas Processing Plant in Texas.

In an action alert, advocacy organization Earthworks said the Maritime Administration should better evaluate the project’s effects on the price U.S. consumers pay for natural gas, as well as regional air pollution and the climate.

The terminal has the potential to emit more than 9 million tons of greenhouse gases per year, the equivalent of nearly 670,000 cars and trucks driven for a year, according to permit documents. Despite this, the Maritime Administration’s environmental impact statement does not mention the project’s impact on the climate, according to Earthworks.

The facility could also emit up to 29,000 tons per year of health-harming “criteria” air pollutants, which can form smog and soot, along with 12,400 pounds per year of hazardous air pollutants.