A group of St. Tammany Parish residents hoping to stop Helis Oil & Gas from drilling a fracking well in the parish has sent letters to the U.S. Army Corps of Engineers and the Louisiana Department of Environmental Quality urging them to halt consideration of Helis’ application for a wetlands-mitigation permit.

The two letters, sent Tuesday, allege that Helis failed to properly fill out parts of its permit application.

If the agencies refuse to suspend the permitting process, Concerned Citizens of St. Tammany, the group behind the letters, plans to ask the courts to issue a temporary restraining order.

Marianne Cufone, the attorney who sent the letters, said that because the Corps of Engineers didn’t make Helis’ entire permit application available without a formal Freedom of Information Act request, the public was not given due notice of the application.

The letters are just the latest maneuver in a battle over Helis’ plans to put a single well on an undeveloped 960-acre tract near Lakeshore High School. Ever since word of the plans emerged, various individuals and groups have mounted a vigorous opposition.

In addition to packing public meetings — often waving signs and sporting specially made T-shirts — fracking critics have flooded local elected officials and regulatory agencies with emails and calls demanding they stop the well. Some elected officials, such as Covington Mayor Mike Cooper and Abita Springs Mayor Greg Lemons, have publicly announced their opposition to the well.

Helis has failed to attend many of those public meetings, but it has issued written statements stressing its commitment to safety.

The actual drilling pad is an area of about 10 acres off a private road. The company has proposed drilling 13,000 feet into the ground — through the Southern Hills Aquifer, which supplies the parish’s drinking water — to the Tuscaloosa Marine Shale formation, which stretches like a belt across Louisiana’s midsection, from St. Tammany Parish to Texas.

Although Helis has just one test well planned for now, the company has options on 60,000 acres in St. Tammany Parish, according to an April letter sent to parish and school system officials.

Cufone’s letter to the Corps says the agency’s public notice of Helis’ application fails to provide enough information “to give a clear understanding of the nature and magnitude of the activity” because it does not make the whole application public. It says the Corps should restart the public comment period, which ends Thursday, “so that all interested parties have adequate time to review and provide meaningful comments on this proposal.”

Corps spokesman Ricky Boyett said the agency is confident the application was proper and everything was in order.

Full applications are not automatically public record because they may contain proprietary information, he said. But, he said, due to the number of requests for Helis’ application, the Corps will put the full application online Thursday. There are no plans to extend the public comment period, he said.

In her letter to DEQ, Cufone alleges that the application submitted by Helis doesn’t say where the company is incorporated, list its officers, provide an estimated schedule of development or say whether wastewater treatment is planned before water is discharged. These omissions invalidate the application, Cufone argues.

Cufone’s letter is currently under review by DEQ’s legal department, a spokesman said.

To get oil from the Tuscaloosa Marine Shale, Helis plans to utilize a method known as hydraulic fracturing, or fracking. In that process, massive amounts of water, sand and a chemical cocktail are injected into the ground to create cracks in the rock formations through which oil and natural gas can be pumped to the surface. The method has been blamed for a variety of health and environmental problems in other areas.

Last week, the company agreed at the request of parish officials to delay a planned “unitization hearing” by 30 days. The hearing, originally scheduled for this week, is intended to set the boundaries of a drilling unit. It does not examine the potential impacts of the well on the environment or consider public sentiment. A unit order, however, must be obtained before a company can apply for a drilling permit.

The company also agreed this week to drill the well in phases, first drilling a vertical well only and testing samples from the target depth before deciding whether to drill the horizontal portion of the well and start the fracking process. Testing the samples could take three to four months.

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