AUGUSTA, Maine — A remote mountain in the woods of far northern Maine is once again the focal point of a major debate over mining as landowners seek sweeping changes to state regulations in response to the rising price of gold and silver.

Environmental and conservation groups are accusing the state’s largest landowner — J.D. Irving — as well as some lawmakers of attempting to rewrite Maine’s mining regulations in the span of a few weeks without adequate public scrutiny or debate.

The result, opponents warn, could be poisoned lakes, streams and groundwater sources near Bald Mountain and other Maine places where gold, silver and other valuable metals are locked away in the bedrock.

“I don’t think I have ever seen a piece of business done in the Legislature this way, at least not a piece of major environmental legislation,” Jeff Reardon of Trout Unlimited in Maine said Tuesday.

Bill supporters, meanwhile, said they have no intention of weakening Maine’s environmental standards and that new technologies have made mining dramatically safer from an ecological standpoint. But they suggested that Maine’s existing regulations — adopted 21 years ago — have stymied growth of a natural resources industry that could create hundreds of jobs in rural areas for decades to come.

“Since the law changed in 1991, not a single permit has been issued for a metallic mine” in Maine, Anthony Hourihan, director of land development for Irving, said Tuesday during a phone interview. But from Irving’s perspective as both a long-term landowner in the state and a major employer of Maine workers, the project “has to be done right,” he said.

“If it can’t be done without creating environmental legacies, it shouldn’t be done,” Hourihan said.

Lawmakers in Augusta are holding work sessions all this week on a last-minute bill sponsored by Rep. John Martin, D-Eagle Lake, that would remove the Land Use Regulation Commission from the mine permitting process. Instead, all permitting would be consolidated within the Department of Environmental Protection.

The proposal also would rewrite regulations regarding mine waste storage, monitoring and reclamation of the land after mining operations cease.

Although the proposals would apply statewide, they were inspired by renewed interest in the potential big-money metal deposits buried in Aroostook County’s Bald Mountain. Irving, which jointly owns the property with Prentiss & Carlisle, estimates the project could create 700 jobs and generate $120 million in tax revenue.

Geologists have known for nearly 40 years that Bald Mountain — located west of Ashland and Portage — harbors significant deposits of gold, silver, copper and other valuable metals. But despite years of research and expenditures topping $25 million, none of the half-dozen companies involved in the property over the decades have successfully mined the site.

The costs of extraction and permitting have been major factors for the inaction, although the rising price of gold, silver and copper has revived interest in the project. And then there are environmental concerns tied to “metallic sulfide mining.”

The Maine Geological Survey estimates that the Bald Mountain deposit contains roughly 30 million tons of sulfide, 2.4 million tons of rock containing copper and 1.4 million tons containing gold and silver. But those precious metals are found at trace levels — estimated at 0.02 ounces of gold per ton of rock and 0.04 ounces of silver per ton.

Capturing those metals would require removing massive amounts of sulfide rock — dubbed “overburden” — and then likely using chemicals such as cyanide to separate the valuable metals from the rock in a process resulting in hazardous wastewater.

Compounding the environmental concerns, the massive amounts of overburden contain sulfide, which reacts with air and precipitation to produce sulfuric acid. The resulting “acid mine drainage,” if left untreated, can contaminate groundwater sources and poison nearby water bodies, killing fish and other wildlife.

While mineral mining is a small industry in Maine today, residents of the Blue Hill peninsula need not look far to find examples of the environmental impacts from metallic sulfide mines in the days before protective regulations.

Acid mine drainage from the former Callahan mine in Brooksville and the Kerramerican mine in Blue Hill has contaminated area coastal sites and streams, requiring massive cleanup projects. The Callahan mine is a federal Superfund site.

Whether the proposed regulatory changes pending with lawmakers will adequately address those pollution concerns is a matter of debate.

Irving’s Hourihan said mining technologies have changed in recent years and new treatment options help avoid the environmental problems found at older sulfide mines. But he said the current regulatory system is too burdensome to navigate and does not offer enough flexibility to accommodate new technologies.

“Basically, the different folks we have been talking to said, realistically, it is almost impossible to permit a mining operation in Maine now,” Hourihan said.

But Reardon with Trout Unlimited said the late introduction of the bill — in the final weeks of the legislative session and without prior notice — means that his and other groups have had no time to study the issue.

Sean Mahoney with the Conservation Law Foundation pointed out that the late-session proposal would scrap and replace regulations that took a special committee more than a year to develop in 1990 and 1991.

“As drafted, it is breathtakingly broad and is such an overreach that in the first work session it was clear that even the attorneys couldn’t defend it with a straight face,” Mahoney said.

Mahoney said he hopes lawmakers will defer judgment on the bill and instead spend the rest of the year studying the issue before next year’s legislative session.

Sen. Thomas Saviello, R-Wilton, chairman of the Environment and Natural Resources Committee, said Monday that the committee plans to devote at least four days to the issue this week and likely will continue into next week, pending approval from legislative leaders. This is the only major issue left on the committee’s plate.

Hourihan said Irving is optimistic that lawmakers can complete work on the bill this session, noting that it would likely take at least one to two years for the rulemaking process plus time for permitting. But if lawmakers were unable to complete work on the bill this session, he added, “Bald Mountain will stay as it is today.”

“For us, it’s about getting this right,” he said.