For the second time in less than a week, a state district judge has dealt a serious blow to opponents of a plan to drill a fracking well in St. Tammany Parish.

The latest rebuff came from Judge William Morvant, of the 19th Judicial District in Baton Rouge, who ruled Monday that state law prohibits parish authorities from stopping Helis Oil & Gas Co. from acting on its state-issued drilling permit.

It followed a decision Friday by a judge in Covington that the town of Abita Springs lacks the authority to enforce zoning laws outside of its boundaries.

In his ruling at the end of a nearly hourlong hearing, Morvant came down on the side of the arguments presented by Helis and the Louisiana Office of Conservation, which said the state constitution expressly gives the Legislature the right to regulate the oil and gas industry. In turn, they said, the Legislature has delegated that responsibility to the Office of Conservation, which is part of the Department of Natural Resources.

“This expressly forbids St. Tammany Parish from interfering or prohibiting the drilling of a well,” Morvant said.

The doctrine at issue, known as pre-emption, states that the state law trumps parish law when the two conflict.

Morvant said any attempt by the parish to interfere with Helis’ permits would be unconstitutional.

He also rejected arguments by attorneys for the parish and for the group Concerned Citizens of St. Tammany, who conceded that the state has the right to regulate oil and gas but argued that the parish has dominion over land use.

The proposed well site, in a wooded tract east of La. 1088, about a mile from Lakeshore High School, is zoned residential. That zoning prevents industrial uses such as fracking, opponents of the well have argued.

In addition, Carl Conrad of the law firm Blue Williams, which represents the parish in the fracking dispute, argued that a provision in state law that requires the commissioner of conservation to “consider” a parish’s master plan actually requires him to “adhere to” that plan.

Morvant disagreed with Conrad’s interpretation. “That flies in the face of the plain language of the law,” he said.

Matt Jones, an attorney for Helis, said Commissioner of Conservation James Welsh did consider St. Tammany’s master plan when he issued a drilling permit on Dec. 19. The permit had a list of attached conditions, which Jones said were evidence of that consideration.

Morvant agreed, saying Welsh “clearly fulfilled” the requirements of the law.

Morvant issued a final ruling on those two issues, saying that he knew an appeal is likely. “I would like to see them before the Court of Appeal or the Supreme Court as quickly as possible,” he said.

Helis spokesman Greg Beuerman said the ruling vindicated what the company has been saying all along.

“Energy issues are governed by the state of Louisiana,” he said.

Marianne Cufone, an attorney representing Concerned Citizens of St. Tammany, said she was disappointed with Morvant’s decision, which she said sets a dangerous precedent.

“Now all the state’s zoning is subject to (the Department of Natural Resources),” she said. “We could have an oil and gas well in the middle of Baton Rouge.”

Nevertheless, Cufone wouldn’t commit to an appeal, saying that the members of CCST will have to map out their strategy going forward.

Conrad also demurred when asked about an appeal, saying parish authorities would make that decision.

Parish Councilman Jake Groby, who attended the hearing, said he would push for an appeal.

“I plan to request that they explore the option deeply,” Groby said. The ruling “is the beginning of the industrialization of St. Tammany Parish,” he added.

Groby acknowledged, however, that persuading some of his colleagues to go forward with an expensive suit might be difficult.

Parish President Pat Brister issued a statement that seemed to afford the ruling some finality. “The court has given us an answer about where the state’s authority ends and where St. Tammany’s begins,” she said.

Morvant’s ruling follows one issued Friday by Judge William Knight in Covington. In his ruling, Knight dismissed a suit brought by Abita Springs against Helis to prevent the well from being drilled. Knight ruled that Abita Springs has no right to attempt to enforce parish zoning rules outside the town limits.

Other legal challenges to the project remain — most notably a federal lawsuit filed by Abita Springs against the U.S. Army Corps of Engineers. That suit accuses the Corps of illegally denying a request for a public hearing on Helis’ application for a permit to drill in wetlands; that application is still under review by the Corps.

No hearings have been scheduled in the federal suit.

Controversy over Helis’ plans has raged fiercely in St. Tammany Parish since they first became public in April 2014.

The company has proposed drilling a 13,000-foot-deep well on a wooded tract north of Interstate 12. The goal is to determine if the site could be a viable commercial producer of oil through the process of hydraulic fracturing, or fracking. When a well is fracked, water, sand and other chemicals are injected into the rock formations to create tiny fissures, through which oil and natural gas can be extracted.

Proponents have said the increased production from fracking has helped spur a reduction in American dependence on imported oil.

But the process is controversial around the nation, where it has been blamed for many environmental and health problems. Some communities have attempted to ban it, with varying degrees of success.

In St. Tammany, opposition has focused on the potential threat to the parish’s water supply in the Southern Hills Aquifer.

Opponents have taken their campaign online and to public meetings and courtrooms.

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