Obama administration on Wednesday authorized natural gas exports from a fourth U.S. facility, unexpectedly accelerating a review process that would-be gas exporters and their allies in Congress had criticized as too slow.

This speed at which the latest approval was reached - just five weeks after the previous project - puts the Department of Energy on a potential pace to rule on several more projects before year's end.

But the permits are drawing concerns from skeptics of unlimited exports who warn that the United States risks giving away the nation's economic advantage of cheap and abundant energy. They warned that the nation is quickly approaching a threshold that could lead to a spike in natural gas prices that would harm consumers and businesses.

Dominion Resource Inc's conditional permit for liquefied natural gas exports from its Cove Point terminal on Maryland's Chesapeake Bay came just over a month after the Energy Department approved exports from a terminal in Lake Charles, Louisiana.

Dominion's was the fourth natural gas export permit issued by the administration. It was the third permit issued this year, following a pause of nearly two years in review of applications to export gas to all but a handful of countries covered by free trade agreements.

Cove Point's conditional approval to export up to 0.77 billion ft³ a day of natural gas, pushes the overall amount of gas exports permitted to 6.37 billion ft³ a day.

With domestic production of natural gas booming, about two dozen projects are seeking to send surplus gas abroad.

Just a decade ago, many were worried that the United States would have to import more gas to meet its energy demands. The swift change in energy fortunes sparked an intense debate over how the United States should handle its newfound gas wealth.

After approving Cheniere's Sabine Pass terminal in 2011, the department took a nearly two-year break in its export review while it commissioned two studies on the economic impact of exports to weigh these concerns.

Elena McGovern, an energy analyst for the Eurasia Group, said the latest permit "indicates a willingness on the part of the DOE to continue steadily processing pending approvals, rather than take a pause in order to review pricing impacts or other considerations."

But a group of industrial companies led by Dow Chemical has argued that unfettered exports will hinder the resurgence of U.S. manufacturers who are currently enjoying cheap gas prices.

America's Energy Advantage, the industry coalition making the case against unlimited exports, called for the department to immediately undertake an evaluation of the impact of its decisions so far and to "clearly articulate in advance its criteria" for determining whether additional exports are in the public interest.

The department acknowledged that after Cove Point, its approvals had crossed the 6 bcf a day threshold that was considered the "low" export scenario in the economic study it commissioned to explore the economic impact of gas exports.

Analysts in a Reuters poll last month predicted that LNG exports would hit 6.3 bcf a day by 2020, once several approved projects are operating.

"The United States is now squarely in the range that experts are saying is the most likely level of U.S. natural gas exports," said Senator Ron Wyden, the Democratic chairman of the Senate Energy Committee.

Before approving any exports above that range, Wyden said the agency must examine the most recent data about the U.S. natural gas supply and demand to prove that exports will not have a "significant impact on domestic prices."

Wyden and other export critics have complained that the study, commissioned by the Department of Energy and released in late 2012, on the economic effects of sending gas abroad used outdated data.

Potential Pause?

To address these worries, the department may pause its review process around year-end to consider new information provided in the Energy Information Administration's preliminary annual energy outlook for 2014, which is expected in December, ClearView Energy Partners said in a research note.

Still, the consulting firm said that the department could approve three more projects this year if it continues to move in one-month increments.

Next in line for review by the DOE is an expansion of Freeport LNG's terminal, followed by Sempra's Cameron LNG project and Veresen Inc's Jordan Cove project.

The department has picked up the pace between approvals. Nearly three months passed between decisions on Freeport LNG's Quintana Island, Texas terminal and the Lake Charles terminal, which was okayed on Aug. 7.

While defending its commissioned LNG export study as "fundamentally sound," the department pledged in the Cove Point order that it would "continue taking a measured approach in reviewing the other pending applications."

Some boosters of gas exports said the administration should move faster to approve pending applications.

"The United States has a narrowing window of opportunity to join the global gas trade," Senator Lisa Murkowski, the top Republican on the Senate energy committee, said in a statement.

Noting that Cove Point filed its application in 2011, she called on the department to move with "timely purpose" to the next decision.