The Empire Mine State Historic Park has been fined $138,000 after failing to meet a deadline to clean up the Magenta Drain, a polluted creek that flows into Veterans Memorial Park in Grass Valley.
And they face an estimated total penalty of nearly $500,000 before they complete a remediation project for the stream.
But the delay caused by a decision to use a passive treatment system will end up saving the state $2 million in construction costs and more than $32 million over the life of the system, according to a state parks spokesman.
The California Regional Water Quality Control Board issued two complaints against the park for violations in water quality that occurred after a May 2010 deadline for compliance. According to the complaints, serious violations in the levels of arsenic were recorded in June, July, August and September - as much as 35 times the allowable limit in June.
Unacceptable levels of iron and manganese also were recorded; manganese can cause symptoms similar to Parkinson's disease and recently has been linked to lowered intellectual function in children.
The Magenta Drain is a small creek that sends polluted water downhill from 367 miles of flooded and abandoned mine shafts in the state park. It flows through Memorial Park and eventually into South Wolf Creek and Wolf Creek, on to the Bear River and, eventually, the Pacific Ocean. The drain originates in a mine shaft and hits daylight in Woodpecker Ravine above the city park. It's course fenced off through the park, the stream flows past the tennis courts, large barbecue area, the veterans memorials and a children's playground area.
The Empire Mine closed in the mid-1950s after producing 175 tons of gold over 106 years - one of the richest mines in California. The state bought the mine for a park about 30 years ago and removed 46,000 tons of contaminated sediment from the area from 1986 to 1989.
After filing a lawsuit in 2004 over pollution in Little Wolf Creek, the environmental group Deltakeeper hammered out a compromise in 2006 with the state's Department of Parks and Recreation to clean up the Magenta Drain. The water board gave Empire Mine four years to plan and build a treatment system, despite pleas from Wolf Creek Community Alliance members to speed up the timeline.
"Arsenic is a pretty serious toxin that is very, very, common in tailing piles," said alliance board member David Brownstein. "We have a lot of big tailing piles sitting around here, at the Empire Mine and on private land. A hundred years of mining gave us an interesting history, but also a toxic legacy."
Manganese also is a serious pollutant and was one of the main concerns for Grass Valley when the city sued Newmont Mining Corp. over treating contaminated water from an abandoned gold mine, Brownstein noted.
Seven months have passed since the deadline for compliance - but a treatment system has not been built. The state water board issued the first complaint in November and a second complaint on Jan. 7.
"By May 18, 2010, they had to install some sort of treatment system to meet effluent limits," said water board compliance and enforcement supervisor Wendy Wyels. "Because they did not, under the California water code, we have to issue mandatory minimum penalties."
The parks department was assessed the minimum penalty of $3,000 per violation, Wyels said. The water board tests waterways for various pollutants, and they can tested more than once monthly; Wyels estimated missing the deadline is costing State Parks about $30,000 a month.
"We understand from their progress reports that (the treatment system) won't be (completed) until October 2011," Wyels said. "They are looking to install a wetlands treatment system, using plants to remove the metal."
Wyels added the state parks department has not paid the penalty for the first complaint or contacted her office, and the matter had been put on the agenda of a board hearing set for Feb. 2-4. The deadline for a response to the second complaint is Feb. 7.
"They have two options," Wyels said. "They can pay the entire amount, or they can put a portion into an environmental project. If they want to propose a project, they can - but it can't be to correct this problem. It needs to be in the same watershed, however."
Penalties can be waived only in certain cases, such as natural disaster or provable lab errors, which is not the case here, Wyels said.
Empire Mine park faces two challenges, Sierra Fund CEO Elizabeth Martin said: The acidified water in the Magenta Drain and the dust exposure on the trails.
According to Martin, one big issue that has hampered progress is that "abandoned mine remediation isn't very well understood."
The delay was partially due to "insufficient staff and expertise to properly evaluate and determine the best course of action to achieve the deadline," parks spokesman Roy Stearns wrote.
At first, the Parks Department planned to treat the groundwater discharge from Magenta Drain with a full-scale, active treatment plant that would have included sludge ponds, settling ponds and chemical storage areas.
But that plan had a significant downside, including increased secondary waste generation, increased truck traffic from chemical deliveries and sludge hauling, and high ongoing capital and operating costs, Stearns wrote.
Instead, the department has chosen a passive treatment system with a settling pond screened by trees and two engineered wetlands, and a pump station in a shed out of public view.
This passive system will have much less impact to nearby residents than an active treatment system, will not require hauling of chemicals, and replacement of the substrate in the wetland would only be required every 10 to 20 years, Stearns wrote.
"A green, sustainable solution, when viewed on a long-term basis, is more advantageous than a heavily engineered, full-scale treatment plant, which would have a large carbon emission footprint over the long term," Stearns wrote.
The passive treatment system will cost substantially less, Stearns said. The construction cost is estimated to be $4 million, as opposed to $6 million for an active treatment plant. And the annual cost is estimated at $2,500 per year, compared to $600,000 for an active system. The state is projected to save an estimated $32 million over the life of the treatment plant.
To contact Staff Writer Liz Kellar, e-mail firstname.lastname@example.org or call (530) 477-4229.