Posted on October 20, 2014 by Bob Berwyn
All-out remediation effort targets acid mine drainage near Keystone Ski Area
By Bob Berwyn
FRISCO — For decades, the abandoned Pennsylvania Mine has been oozing heavy metals — zinc, manganese, cadmium, lead and and arsenic — into the waters of Peru Creek, a small tributary of the Snake River near Keystone, Colorado. The site has been the focus of intensive study during the past 15 years with the goal of improving water quality downstream.
Last week, engineers and environmental experts took a big step toward trying to staunch that flow by blocking one of the mine tunnels. If all goes well, the new bulkhead could reduce the direct discharge from the mine by about two-thirds, said Jeff Graves, a remediation expert with the Colorado Division of Reclamation Mining and Safety.
Graves explained that the new plug should force the water back into its natural underground pathways, trickling and percolating down through layers of rock and earth, and not as prone to the oxidation that’s key in the formation of acid mine drainage. Essentially, the work will restore the groundwater flow to more natural, pre-mining conditions, he said. Continue reading
Filed under: Environment, rivers, water, water quality | Tagged: abandoned mine pollution, acid mine drainage, EPA, Pennsylvania Mine, Peru Creek, Snake River Colorado, Snake River watershed task force | Leave a comment »
Posted on October 19, 2014 by Bob Berwyn
Storage still near all-time lows
A 2014 water year map shows the continuing drought conditions in California, as well as dry patches from Texas, extending north into Oklahoma.
FRISCO — Near-average inflow to Lake Powell the past 12 months helped maintain storage at a similar level to last year in the key Colorado River reservoir. According to the Bureau of Reclamation. Continue reading
Filed under: Colorado, Environment, rivers, water | Tagged: 2014 water year, Colorado River, drought, Lake Powell | 1 Comment »
Posted on October 19, 2014 by Bob Berwyn
Microclimates may partially buffer some streams, at least temporarily, from warming air temperatures. bberwyn photo
‘The one constant is that a healthy watershed will be more resilient to climate change than one that isn’t healthy …’
FRISCO — Global warming is all but sure to raise stream temperatures in many areas, but it turns out that changes in air temperatures don’t offer a reliable proxy for projecting those changes.
Eapecially in the mountains streams of the West, topography and riparian conditions are huge factors in regulating stream temperatures.
The correlation between air temperature and stream temperature is surprisingly tenuous, according to stream ecologists at Oregon State University, who examined historic stream temperature data over a period of one to four decades from 25 sites in the western United States. Continue reading
Filed under: climate and weather, Environment, global warming, rivers, water | Tagged: aquatic ecosystems, climate change, global warming, stream temperatures | Leave a comment »
Posted on October 16, 2014 by Bob Berwyn
Is there mercury in your trout?
National assessment by USGS pinpoints regional mercury hotspots
FRISCO — Widespread mercury contamination is one of the many signs of continued global environmental degradation. Currently, there are fish consumption advisories for mercury in all 50 states in the U.S. Methylmercury concentrations in fish exceed the human health criterion in about one in four U.S. streams.
A new USGS report takes a comprehensive look at mercury contamination in streams across the United States, finding the highest concentrations in the Southeast and in the West, where some streams were degraded by historic mining activities.
Mercury is a potent neurotoxin that accumulates in fish to levels of concern for human health and the health of fish-eating wildlife. Much of the mercury originates from combustion of coal and can travel long distances in the atmosphere before being deposited. This can result in mercury-contaminated fish in areas with no obvious source of mercury pollution. Continue reading
Filed under: Environment, rivers, water, water quality | Tagged: Environment, mercury pollution, mercury stream assessment, USGS, water quality | 1 Comment »
Posted on October 6, 2014 by Bob Berwyn
How pure is your groundwater?
Iowa stream sampling shows common drugs turning up in well water
FRISCO — Research in a small stream near Des Moines, Iowa shows how pharmaceuticals and other hard-to-remove pollutants from treated municipal wastewater can travel into shallow groundwater following their release to streams.
“Water level measurements obtained during this study clearly show that stream levels drive daily trends in groundwater levels,” said Paul Bradley, lead author of the new U.S. Geological Survey study. Continue reading
Filed under: Environment, rivers, water, water quality | Tagged: Environment, groundwater, Persistent organic pollutants, pharmaceuticals, water quality | Leave a comment »
Posted on September 27, 2014 by Bob Berwyn
Salmon fisheries at risk with open-pit mine proposal
The EPA will be allowed to do a thorough evaluation of the impacts of a proposed copper mine in Alaska’s Bristol Bay, a federal judge has ruled.
By Bob Berwyn
FRISCO — A federal judge Friday ruled that the EPA can proceed with an environmental review of a proposed copper mine in Alaska’ pristine Bristol Bay.
U.S. District Court Judge H. Russel Holland rejected arguments that the EPA exceeded its authority by starting the review process in the absence of a specific permit application, and that the review violates the Alaska Statehood Act.
At issue is the proposed Pebble Mine, which would, according to environmental groups, become the largest copper mine in the world, potentially tainting huge areas of productive salmon habitat with dredged material and other pollutants. Continue reading
Filed under: Environment, rivers, water, water quality, wetlands | Tagged: 404 permit, Bristol Bay Alaska, Environment, EPA, mining, Pebble Mine, salmon | 1 Comment »
Posted on September 19, 2014 by Bob Berwyn
Microbeads are pathway for other environmental contaminants
FRISCO — Microplastics have long been documented as an environmental threat to oceans. European researchers recently warned of similar problems in Italian lakes, and now, Canadian scientists say they’ve found 2-millimeter plastic microbeads widely distributed along the bottom of the St. Lawrence River.
The team of researchers from McGill University and the Quebec government published their study this month in the Canadian Journal of Fisheries and Aquatic Sciences.
The paper explains that the pollution probably comes from cosmetics, household cleansers, or industrial cleansers, to which they are commonly added as abrasives. Owing to their small size and buoyancy, they may readily pass through sewage treatment plants. Microplastics are a global contaminant in the world’s oceans, but have only recently been detected in the surface waters of lakes and rivers. Continue reading
Filed under: Environment, rivers, water, water quality | Tagged: plastic microbead pollution, Stt. Lawrence River, water polluton, water quality | Leave a comment »