The Crested Butte News Serving the Gunnison Valley since 1999
County recommends all Irwin wells get tested
By Mark Reaman
Gunnison County is alerting property owners in Irwin that tests conducted on individual domestic wells in the Irwin area have shown high levels of some heavy metals in the water.
As a result, the county recommends all residents in the Irwin area have their wells tested. Arsenic appears to be the most prominent metal found in the tests but there are indications of other heavy metals in the area as well.
According to Gunnison County community development director Russ Forrest, the U.S. Environmental Protection Agency conducted testing a year and a half ago on nine domestic wells belonging to residents who voluntarily let the agency test the water.
The EPA also tested surface water, ground water and soils in the Irwin area. The results of the tests were recently sent to the county. After looking them over, the county believed the results warranted alerting the public.
Forrest said the county heard Wednesday, February 17 from the state that only those who participated in the testing were made aware of the results, so the county felt it important to make this information available to those individuals who may be affected.
According to the EPA report, arsenic levels exceeded government safety standards. “Except for one sample (at the Forest Service North Campground) total arsenic was detected in all drinking water samples at concentrations exceeding its Cancer Risk,” the report states. “One drinking water sample collected during the Phase I investigation contained total arsenic above the Maximum Contaminant Level…”
In a press release from the county, it was recommended that residents in the Lake Irwin Townsite and the properties around Lake Irwin test their wells at this time for heavy metals. Residents and property owners in the Lake Irwin area are receiving notices from Gunnison County that include guidance about how to test private wells.
“The main message to the public is that they should get their private wells tested,” explained Gunnison County public health director Carol Worrall. “Heavy metals can be found in well water and that’s why this message about testing is important. Without testing, it is hard to say what would need to be done. Consultation with state water experts did not advise anything beyond testing at this point.”
EPA toxicologist Bob Benson said high arsenic levels could have a detrimental impact on human health. “We know arsenic is a known carcinogen,” he said. “It can cause skin and bladder cancer and result in skin lesions. Typically in cases like this, the agency notifies the well owner of the test results and the homeowner has to make his or her own choice on how to use the water.”
EPA site assessment/project manager Jean Wyatt said the testing took place in 2014. It took some time to compile the results and prepare letters to the well owners.
Wyatt said the source of the arsenic remains a mystery. There is no evidence that it is emanating from old mine sites. And arsenic can occur naturally. “We just cannot figure out hydrogeologically what is causing it,” Wyatt said.
According to the EPA report, given that a glacial moraine formed Lake Irwin, there is a possibility the elevated concentrations of arsenic could be attributed to sediment from the moraine in Lake Irwin.
The sources of hazardous substances associated with the Ruby District West site also include contaminated soils, mine tailings and waste piles at mines, adits, and exploration pits, according to the report. “Due to the many potential different sources in the area and complex hydrogeology in the area a detailed investigation would be needed in order to fully determine sources and contributions to ground water contamination in the town of Irwin,” the report states.
Wyatt said when looking at one-time sampling, it is difficult to conclude if there is a long-term problem. “Frankly, it’s hard to figure out if it’s constant or if the levels change depending on what’s going on water-wise,” she explained. “It’s a snapshot. That’s one of the problems with mine sites in general. There are so many components and trying to identify what’s really going on is difficult. It’s not unusual to see different sample results during high water flows and low flows.”
Despite the extensive sampling investigation no definitive source of contamination could be specifically attributed to the higher levels of metals in these wells, so EPA was unable to take an action, Wyatt noted.
The town of Crested Butte has been notified of the Lake Irwin water issue since some of that area is located within the town of Crested Butte’s watershed. “The town is now tracking the issue,” a press release from the town stated Friday afternoon. “Lake Irwin lies within the Town’s watershed. However, the Town of Crested Butte regularly tests incoming water at its intake. Heavy metal levels at the Town’s intake are well below the State of Colorado maximum contaminate level (MCL) for human health. Water is then treated at the Crested Butte treatment plant before distribution to end users on the Town water system.”
According to EPA remedial project manager Sabrina Forrest, the EPA did not conduct the testing based on any single incident but was getting information in the vicinity of old mines the agency is monitoring.
The EPA concluded, “updated data and target information would help determine if more Superfund program involvement was needed.” That decision has not been made.
Wyatt emphasized that the homes with private wells are located in highly mineralized mining areas. “It is not unusual to see elevated metals concentrations in groundwater in such naturally occurring mineralized areas,” she said. “Because of the extremely complex hydrogeology and the presence of naturally occurring high metals, mining sources could not be conclusively identified. Even a more extensive hydrogeologic investigation may still not fully determine the source of the metals. Due to these reasons, the specific homeowners have been provided information on a home treatment system to reduce metals in their drinking water to a protective level.”
Citizens can test their wells through a number of sources. Gunnison County recommends contacting the Colorado State University Extension to conduct a heavy metals test. The test costs approximately $240 and produces results within seven to ten days. Testing can be done through the Colorado State University Extension office in Gunnison. Concerned property owners can contact Eric McPhail at (970) 641-1260.
