Mine project threatens Bristol Bay salmon fishery: EPA report

Source: Seattle PI

Seattle PI - Joel Connelly

The great fishery in Alaska’s Bristol Bay should beware diggers of open pit gold mines,  erectors of 685-foot-high tailings dams and builders of haul roads that cross salmon-spawning streams, according to a detailed — and devastating — new federal analysis.

According to the latest revised scientific assessment by the U.S. Environmental Protection Administration, a multi-billion-dollar mining project, located cheek to jowl with two major salmon-spawning streams, could have near and long term impacts on the world’s largest sockeye salmon fishery.

The river systems of Bristol Bay, where many Seattle fishers go each year, generates about $500 million in direct economic expenditures and sales each year, and has provided employment for more than 14,000 full- and part-time workers.  Bristol Bay supports major commercial, spot and native fisheries.

The “mine footprint” would be potentially enormous and fall between the Nushagak and Kvichak rivers,  largest of the Bristol Bay watersheds.

The two rivers account for half of Bristol Bay’s salmon production.  The annual commercial harvest averages 25.7 million sockeye salmon .

“The Pebble deposit, the most likely site for near-term, large-scale mine development in the region, is located in the headwaters of tributaries to both rivers:  Therefore, both of these watersheds are subject to potential risks from mining,” said the EPA’s scientific assessment.

The Bristol Bay Native Corp. and nine tribes have asked the Obama administration to use the Clean Water Act to block mining development.  Two foreign companies, the London-based Anglo American and Canada’s Northern Dynasty Minerals, have proposed the huge mining development.

Sen. Maria Cantwell, D-Wash., a critic of the proposed mine, said Friday:  “This report is evidence of the devastating impact that the proposed Pebble Mine would have on Bristol Bay salmon and the thousands of Washington state jobs that depend on them.”

After examining three mine scenarios, the EPA’s listing of potential impacts includes:

–Mine Footprint: Depending on which mine scenario is developed, 24, 56 or 90 miles of streams would be lost due to mine pits, tailings storage facilities, waste rock piles, and the elimination, blockage or dewatering of the streams.  Either 5, 15, or 22 miles of spawning or rearing habitat for sockeye salmon, Chinook salmon and coho salmon would be lost.

–Stream flow Reductions:  “Altered stream flow due to retention and discharge of water used in mine operations, ore processing, transport and other processes would reduce the amount and quality of fish habitat, the EPA found.  Reductions in flow exceeding 20 percent would “adversely affect habitat” in an additional 9.3, 16 and 34 miles of salmon streams.

–Wetlands loss:  Depending on which mine scenario came about, 1,200 or 3,000 or 4,800 acres of wetlands would be lost, which “would reduce off-channel habitat for salmon and other fishes,” the EPA concluded.  Wetlands provide important rearing habitat for juvenile salmon.

–Waste leakage:  Waste water treatment would, presumably, meet all state and federal standards.  “However,” concluded the EPA assessment, “water quality would be diminished by uncollected leakage of tailings and waste rock leachates from the containment system,” the agency reported.

–Transportation corridor:  Mine development would include major road development, in a region that includes not only spawning streams but IIlliamna Lake, Alaska’s largest freshwater lake.  In the Kvichak River watershed, reportes the EPA, “the transportation corridor would cross 53 streams and rivers known or likely to support migrating and residents salmonoilds . . . The corridor would run near Illiamna Lake and cross multiple tributary streams near their confluence with the lake.

“Diminished habitat quality in streams and wetlands below road crossings would result primarily from altered flow, runoff of road salts, and siltation of habitat for salmon spawning and rearing and production of invertebrate prey.”

The potentially most devastating, and longest lasting, threat to Bristol Bay’s fishery would come if the mine’s tailing dams were to fail.

“Because there is no plan for their removal when mining activities cease, the tailings storage facilities and their component dams are likely to be in place for hundreds to thousands of years, long beyond the life of the mine,” the EPA reports.

One projected tailings dam would be 685 feet high, higher than the St. Louis Gateway Arch and the Washington Monument.

The EPA evaluated two potential failures of tailings dams.  If a dam or dams were to fail, concluded the government’s scientists:

–”There would be a complete loss of suitable salmon habitat in the North Fork Koktuli River along at least 18.6 miles of stream habitat . . . Deposited tailings would degrade habitat quality for both fish and the invertebrates they eat.”  (Deposited tailings would be highly toxic based largely on their copper content.)

–”Ultimately, spring floods and storm flows would carry some proportion of the tailings into the Nushagak River.” The Koktuli River is a major tributary of the Nushagak.

The Koktuli River watershed is a major producer of Chinook salmon.  The Nushagak River watershed, on the whole, is the largest producer of Chinook salmon in the Bristol Bay region:  The EPA estimates its annual runs averaging more than 190,000 fish.

The dangers to Bristol Bay’s salmon fishery would not be temporary.

“The ore deposit would be mined for decades, and wastes would require management for centuries or even perpetuity,” the EPA reports.  “Engineered waste storage systems of mines have been in existence for only about 50 years and their long-term behavior is not known.”

The “Superfund” effort to clean up mine sites and smelter sites in the Northwest has been bedeviled by one more factor laid out by the EPA:

“Mine management or ownership may change over time.  Over the long time span (centuries) of mining and post-mining care, generations of mine operators must exercise due diligence.  Priorities are likely to change in the face of financial circumstances, changing markets for new metals, new information about the resource, political priorities, or any number of currently unforeseeable changes in circumstance.”

The public has until May 31 to comment on the assessment, prepared by the agency’s Seattle-based Region  X office.  The EPA has made no final regulatory determination.

“I look forward to the EPA moving forward and finalizing a Bristol Bay Watershed Assessment,” said Cantwell.  “I will continue to fight to protect Washington fishing jobs.  Because the future of Bristol Bay must be determined by science, not politics.”

But Sen. Lisa Murkowski, R-Alaska, a strong supporter of resource industries in the 49th State, raised alarm that the EPA assessment is a bid to preempt the mine project before any formal proposal is submitted.

“Attempts to prejudge any mining project before the full details of that proposal are submitted to the EPA for review is unacceptable,” Murkowski said in a statement.  “If the EPA has concerns about the impact of a project, there is an appropriate time to raise them — after the permit has been made, not before.

“It is clear to me that a preemptive veto of resource development is quite simply outside the legal authority that Congress intended to provide the EPA.”