The fight over a proposed oil well in St. Tammany Parish made its first appearance in federal court Wednesday, with Judge Carl Barbier probing both sides with questions about the status and nature of the project.

Ostensibly, Wednesday’s hearing at the federal courthouse in New Orleans was prompted by a lawsuit Abita Springs filed against the U.S. Army Corps of Engineers over the wetlands permit the Corps issued to Helis Oil & Gas Co., which is planning to use controversial hydraulic fracturing, or fracking, technology at a three-acre drilling site northeast of Mandeville.

Lawyers from the Tulane Environmental Law Clinic, which is representing the town, argued that the Corps did not provide evidence that it had considered less environmentally sensitive areas for the drilling pad, and therefore the permit should be vacated.

But Barbier’s questions ranged far and wide, occasionally coming back to the Corps permit, but also delving into other subjects, some of which are the subject of state litigation over the project.

In one exchange, he grilled Tulane student lawyer Rachael Ruiz over whether Abita Springs had hired experts to study what other sites would be viable.

“Do you have some suggestions to where else they could do this?” he asked her.

Ruiz replied that she did not, but that the burden lay on the Corps to show in the record that it had considered other sites, something she said was lacking.

“We have no evidence in the record of them looking at other alternatives,” she said.

There was a closed-door meeting on the topic between the Corps and John Johnston of the Louisiana Geological Survey, she acknowledged, but the records of that meeting were scant and did not detail the deliberations she said were required by federal regulations.

Barbier also directed sharp questions at Lisa Jordan, another attorney representing Abita Springs, about whether the town was worried about the well’s potential impact on its water supply in the Southern Hills Aquifer.

The aquifer, Barbier noted, covers a large area.

“Even if they move it, it would be through the aquifer, right?” he asked her.

Jordan tried to steer the conversation back to whether the Corps had followed federal rules when it issued the permit.

“The law says they have to look at non-wetlands, and there is no evidence they did that,” she said.

Barbier noted, however, that Helis submitted four sites, all of which were on wetlands, and said the company concluded that the proposed site was the least environmentally dangerous. What’s more, Barbier said, if a non-wetlands site could have been identified, surely the company would have chosen it.

“What would be the motive to pick a wetlands site with all the hoops they have to jump through?” he said.

Barbier also questioned John Sullivan, a U.S. Department of Justice attorney who represented the Corps at the hearing.

Referring to a letter the Corps sent to Helis in December of 2014 advising that the Environmental Protection Agency had concerns about Helis’ alternate site consideration, Barbier asked if that had ever been addressed.

Sullivan said that the EPA had withdrawn its objection after Helis had submitted a 500-page supplemental packet of information.

“The Corps of Engineers reviewed the new and the old information,” Sullivan said.

Harry Rosenberg, who represented Helis at the hearing, said the company chose the best spot to drill a commercially viable well and be environmentally conscientious.

After an hour and a half, Barbier thanked the attorneys and said he would issue a decision “in due course.”

The federal suit is one of several legal battles over the well, most of which are playing out in state courts. The furthest advanced of those is a suit brought by St. Tammany Parish and the Concerned Citizens of St. Tammany alleging that parish zoning laws should trump state regulations and that the state Department of Natural Resources should not have been allowed to issue a permit for the well.

A state district judge in Baton Rouge ruled in favor of DNR and Helis in that case, but the parish appealed, and that appeal was heard last month at the 1st Circuit Court of Appeal. No decision has been issued.

Construction at the site is on hold while the appeal plays out.

Helis’ proposed well is north of I-12 and east of La. 1088 in a wooded area near Lakeshore High School. The company wants to drill a 13,000-foot vertical test well to collect samples for testing. If the samples are promising, the company plans to drill a mile-long horizontal shaft and hydraulically fracture, or frack, the well.

Fracking is a controversial process that involves pumping water, sand and other chemicals into the ground at high pressure to create tiny fissures in rock through which oil and natural gas can be extracted.

Follow Faimon A. Roberts III on Twitter, @faimon.