GRASS VALLEY, Calif. (KTXL) — Modern life mingles with reminders of the California gold rush across Grass Valley.

Rusty relics of once-thriving gold mines give silent testimony to the rich history upon which the city was built.

Gage McKinney is a historian and award-winning author. His family’s roots in Nevada County go back five generations.

“Forty-niners came in and began with hand tools working the streams,” McKinney explained. “Everything was in such a rush, such a rush forward.”

Three generations of McKinney’s relatives worked at the once-thriving Idaho-Maryland Mine in Grass Valley, originally called the Eureka Mine.

“Discovered about 1853,” McKinney said.

According to McKinney, miners found gold within an outcropping of quartz at the original mine site. From there, they started digging, following that vein of quartz like a treasure map into the earth.

“Down for 30 feet originally, 100 feet eventually, and it made men rich,” McKinney said.

He told FOX40 he wrote a book about one of the men who profited from the mine.

“And his name was Errol MacBoyle and he grew up in Oakland, and he just fell in love with this place,” McKinney said.

MacBoyle was a well-educated mining engineer. He purchased the Idaho-Maryland Mine during a time when it was struggling in the 1920s.

MacBoyle’s crews dramatically turned the mine’s fortunes around.

“Because at Christmas 1927, his miners underground made contact with the Dorsey vein in the Idaho-Maryland Mine, which is the richest vein,” McKinney explained.

Under MacBoyle’s ownership, the mine had some of its most profitable years, and as a result, so did Nevada County.

“There was a tremendous boom and what people said about this county in the 1930s, ‘There is no Depression here,’” McKinney said.

Production at the Idaho-Maryland Mine peaked around 1940 and 1941.

The mine was the richest gold-producing mine in California and the second-highest gold-producing mine in the U.S.

“Well then World War II came along and America had to shift its economy,” McKinney said.

And in the shift, McKinney said the federal government decided gold was non-essential. 

“They really wanted the gold miners to go back to copper mining, that’s what America needed,” McKinney explained.

As the war ended, the price of gold was fixed at $35 per ounce. Inflation was on the rise, the mine had fallen into disrepair and stopped being a profitable venture.

“And so, in 1956, the gold mines here closed in Grass Valley,” McKinney explained.

In its nearly 100 years of operation, the Idaho-Maryland Mine produced 2.4 million ounces of gold, which is 75 tons of high-grade gold.

Some people believe there is more gold still down there.

Ben Mossman, the CEO of Rise Gold, is one of those believers. His company bought the mine 2017.

“This mine is a big deal,” Mossman told FOX40. “There’s very few deposits like this in the world.”

The company did some exploratory drilling and hit what the old-time miners would call “paydirt,” high-grade gold embedded in quartz.

“With our very first hole, we hit very good values,” Mossman said. “So, it has a lot of potential. A lot of work still needs to be done to prove up that potential.”

A large concrete silo is the only structure still standing from the days when the mine was active. The shaft is sealed and covered by a steel plate.

To reopen it and send workers underground, Rise Gold needs approval from the Nevada County Board of Supervisors. A final decision could come by the end of this year.

In the meantime, the company was able to send a camera deep down the mine shaft. 

“Having this shaft that’s still in good condition is a major part of why you can reopen the mine,” Mossman explained.

The rectangular passageway goes underground more than a half-mile into the Earth. 

At Rise Gold’s Grass Valley office, Mossman showed FOX40 maps acquired from the mine’s previous owners, revealing nearly 100 miles of tunnel.

“So, you can see they’ve driven this tunnel along the veins and the red hatching is where they have quartz veining,” Mossman said, referring to the map.

From the information on the old maps, the company was able to create 3D computer models — but reopening the mine is a tall order.

Groundwater has crept in over the years and now fills most of the mine. Rise Gold would have to build a water treatment plant, pump all the water out, purify it and release it into a nearby creek.

Mossman added that the whole process would take about a year.

The process is one of many measures the company would have to undertake to make the mine compliant with the California Environmental Quality Act.

Surveys commissioned by Rise Gold show strong community support for reopening, but the project also has many opponents who say “mining is our past not our future.”

Opponents to reopening the mine have organized an effort called Mine Watch. Mine Watch signs posted around Grass Valley read, “Protect our air, water, quality of life. No mine.”

A recently released draft environmental impact report on the project is more than 1,000 pages thick.

Rise Gold found the report favorable. Mossman said current technology provides for cleaner and quieter gold mining.

“Regulations that are required by the state and the county are very stringent,” Mossman said.

A public comment period is open through April 4.

“And now in this phase, with the public participation, they can look through that report. If they think there’s something that was missed or should be studied more, they can bring that up to the county government,” Mossman explained.

“And the county government will have to consider all of that information before they issue the final report,” Mossman continued. “So, it’s a very robust process. It’s a scientific process and it’s based on very stringent requirements of the state of California.”

If the project is approved, Rise Gold plans to employ 300 people, paying an average wage of 94,000 a year plus benefits.

The Nevada County Planning Commission has scheduled a public comment meeting on the draft environmental impact report for March 24.

Back at the Searls Historical Library in Nevada City, McKinney did not wish to offer his opinion about the future of the mine. He’s focused on the kind of treasures that cannot be bought or sold.

The historian offered nuggets of wisdom in a community remembering its past and pondering its future with the potential of a 21st Century gold rush.

“History is the story that helps people to be rooted where they are and to feel that they belong. And what I want is for us all to continue to feel that this is our home and this is the place where we belong,” McKinney said.