Greg Roczickz of Bethel generally shies away from the politics and corporate
policies tied to any invites
to tour an Alaska mine, but not when UAF's Cooperative Extension Service's involved.
I've been offered tours of
mines in the past mainly sponsored by the industry but the attraction for this one
was the fact it was being done by the University.
[It] raised my level of confidence and the credibility of the information I might be
getting
out of it. That's the idea behind extensions three-day extensive workshop
and tours of Fort Knox
and open pit gold mine outside of Fairbanks and Pogo,
a remote underground mine near Delta Junction. NovaGold Resources is nudging
toward developing a new mine in the middle of the Kuskokwim River drainage.
The goal extension is to provide those downriver from the proposed Donlin Creek
Mine
with the facts so that they can participate in that permitting process
and help determine the region's social and economic destiny.
Until World War two mining was the state's largest employer,
but the industry operated under different environmental standards.
Modern state and federal environmental laws and mining regulations are
relatively new,
and most new mines meet standards that didn't exist a few decades ago.
Part of what we're trying to do is
take some people to a couple modern mines
and give them the opportunity to visit
the mine, see how it operates, see the condition, see how
all the controls that are taken there,
all the employment, and see
how they address all the concerns, and then
to have those people go back to their communities
and share that information in their communities.
We're not trying to convince anybody on
what's the thing to do. I don't have a clue what the answer is
in any of these communities. It's something they're gonna have to decide on themselves,
but they need facts and
pretty objective facts. They need to be able to evaluate what's important to them
and make their own decisions. Bob Loeffler, former director of Alaska Department of
Natural Resources Division of
mining, land and, water, lead the workshops and field tours.
Participants included Annie Cleveland of Quinhagak,
David Paul of Kipnuk, John Phillips Sr. and Mildred Lupie from Kongiganak,
Roczickz and Jonny Evan of Bethel, Nick Alexi of Lower Kalskag,
and Helen Traylor with the Georgetown Traditional Council. Kinross Gold
Corporation leases the 12 square miles encompassing Fort Knox from the state
and the Alaska Mental Health Trust. The twelve-year-old operation extracts
low-grade,
low sulfur ore deposits from an open-pit. The presence of sulfur signals a
potential for acidic conditions,
so low means less need for precautions to prevent acid formation.
The Fort Knox ore for example contains less than half a percent
where Pogo nets about 3 percent. Low-grade on the other hand
equates to less gold, about 0.027 oz. for every ton of rock
compared to Pogo's average of 0.41 oz. per ton.
Decked out in safety gear complete with reflective vest,
hard hat, and safety glasses, the group ventured into the territory of Eric Hill,
superintendent of the three-quarter mile by one and three-quarter mile by 1400 foot deep
open pit. We had to come in here, strip down the overburn
in the brown rock and get the gray rock exposed. So the
granite from here is blasted. We drill a pattern out
30 feet deep, 6.75 inch holes
We fill that with explosives
and we break up the material. Once the materials broken,
our hydraulic shovels come into the materials,
load up the haul trucks, and ship it according
to where it needs to go. If it is A-grade ore, it
feeds to our mill complex and goes form here over to this
building off to our right which is the crushing building and we'll go look at that next. Production began in 1996 and will
continue until 2014,
with an additional two years to process the stockpile.
The mine employs about 400 people, with up to 275 working at any given time.
The staff also include seven environmental engineers.
From the lip of the pit, the 150 ton,
200 ton, and 240 ton trucks with tires as tall as two stacked Shaquille O'Neal's
resemble Tonka trucks. The deeper the pit,
the larger the truck, since it takes more time to haul the rock.
After two shovel dumps, equal to the weight of 75 adult elephants,
a 200-ton truck starts the long hog-backed trek
out of the pit to the gyratory crusher. The control room shimmies and shakes as
the 700 horsepower motor-driven
rock muncher grinds chunks as big as Volkswagens
and then a belt conveys the uniform cantaloupe sized rocks to the mill
or a stockpile. Inside the processing building in the soundproofed control room
overlooking the operation,
a poster addresses safety and environmental concerns.
Down below, safety earplugs barely muffle the rumble and tumble as the
two-story high
SAG mills, aluminum-coated clothes dryers filled with 3-inch and five inch ball
bearings, pulverize the high-gold content rocks.
The resulting gravel and dust falls through a screen onto a conveyor belt
to the Knelson batch concentrator. After adding water, this Tilt-O-Whirl-like
contraption slings slurry around at three G's
until gold-bearing minerals rise to the top and the overflow
goes to the leach tanks, where cyanide is added. The cyanide bonds with the gold as
the mixture flows through a sequence of seven leach tanks.
An activated carbon system, similar to charcoal,
absorbs the cyanide-gold from the fluid. The next tank separates the carbon from
the gold,
and the cyanide and carbon are then used again.. Cyanide is a dangerous yet common
industrial product
used, for instance, to make blue jeans. It also occurs naturally at low levels in
the environment,
but humans die when they ingest too much and so do fish.
The tailings end up in a 20-foot deep lake protected by an even thicker layer of
rock. Stay tuned for more details on this tailings pond. Meanwhile,
over in a little-known area, hand-picked workers melt the dust and pour the molten
gold into bars,
about 82 pounds, ninety-five percent pure,
worth about 1.1 million dollars. One of the council members turned to me and
said this is all about water quailty.
Almost all I've heard is water quality.
Permitting a mine, there are lots and lots of permits,
but it is water quaility, water quaility, water quailty and I said you got it. It is protecting the fish
and water quailty. That is typically the issue in a large mine. Mining companies collect data for
years before addressing water quality permits
and meet many established standards for water quality.
Basically, the mine must not discharge water that would adversely affect people
or fish. To comply with these standards, Fort Knox does not discharge
any water at all. Every aspect that involves a drop of water requires a
permit
and must pass state and federal regulations. That process includes up to
60 permits ranging from food service
to a toilet flush and an environmental impact statement,
or EIS. Written by an agency contracted to the federal government,
this independent review of the mine proposal specifically considers public
input from
village meetings, written comments, and consultations with tribes.
In fact, the public tells the agency what to study
to understand a mine's environmental effects. Some of those study topics include
water quality and flow, rock characterization,
Wildlife and Fisheries, habitat,
wetlands, subsistence and traditional values,
noise and visual, social-economic,
archaeological and cultural, cumulative impacts,
and possible alternatives. No mine proposal can proceed past this point
without approval of everyone involved.
That list includes the Alaska Department of Natural Resources,
Environmental Conservation, Fish and Game,
Transportation and Public Facilities, and the Environmental Protection Agency,
US Army Corps of Engineers ,community leaders, and tribal elders.
I would welcome a mine
in an orderly fashion,
as long as they abide by all these
rules and regulations. Basically,
the developers come up with a three- tiered plan that identifies the risk of
something happening,
the consequences if something happens, and a back-up plan.
In the case of Fort Knox, engineers designed a natural sump or water
fence in which the whole process floats downhill
into a tailings lake and not a drop escapes the mine.
This is commonly referred to as a
a leaky dam construction and
so its designed for
water
to seep through in certain amounts.
When it is constructed,
you have
transition rock on the outside. Then it comes in
and first it hits what is called a
filter zone which is
a low permeability zone. A material that is about five foot
thick. So any water that comes through
the rock dam hits that transition zone
in slow permeability, and it gets carried down and
ends up in a sump down here which is
underneath that pump building. Behind the
filtered zone, you have a sealed zone, which is a
high permeability. So
that seepage then all feeds all back into the dump
and gets pumped up to the black line you see there
and back into the tailings impoundment. Alaska's mind to maintain healthy fish
populations downstream.
In fact, the Fish and Game Department tout Fort Knox for improved pre-mining fish
habitat and increased populations.
The Pogo mine doesn't look quite as spectacular as Fort Knox,
mainly because most of the action occurs underground. Mine operator and manager
Teck Cominco
expects to produce 350,000 to 500,000 ounces of gold annually
or upwards of 5.6 million ounces over the next decade.
Teck Cominco maintains a local hire policy,
with 63 percent of the 257 workers from the area.
Unlike Fort Knox, the gold ore is concentrated in a 12- to-15-foot
wide dipping vein of quartz in the mountainside between Liese creek
and Pogo creek.
Extraction requires considerably less equipment than Fort Knox
and involves a conventional underground mining technique of cut and fill
and drift and fill. An underground water treatment facility handles the high
water flow,
and ventilation fans push 500,000 cubic feet of air per minute
through 15 miles of tunnels to maintain breathable air,
remove diesel exhaust, and heat the air in winter. The processing complex
includes a mill,
barracks, dry stack tailings, waste rock dumps,
a recycled water tailings pond, an airstrip,
gravel pits, fuel storage areas, and a local network of
roads. The mill process parallels Fort Knox,
but due to the higher gold content in the ore, Pogo separates about sixty percent
of the gold through a flotation system
and the rest from vat leaching. As part of the cut and fill process,
operators return more than half of the 11 million tons of tailings,
the crushed rock without gold, mixed with cement,
to the underground cavities. So after we get the gold out at the rock,
we squeeze the moisture out of it with these big pressure filters. I'll show you down there,
these pressure filters.
Then we haul it up here,
place in about 15 percent moisture in and compact it.
This is where in closure,
we'll take that growth media that we saw stockpiled along the
road with tree stumps and all the
organic material, and we'll re-spread that over here.
It will stabilize
and revegitate.
Then we should be able to leave and not have
any long-term issues.
From an environmental standpoint, none of the dry stack involved cyanide
or other difficult chemicals.
And any tailings in contact with cyanide end up underground as cement paste,
so little can potentially leach into the water. Even so,
environmental engineers carefully monitor the dry stack and water from
underground shafts.
Given the rules and regulations, the backup plans, and all the other hands-on
details,
Greg Roczickz of Bethel was still concerned, rightfully so,
about the chemicals in the extraction process, but more importantly, he said
people need to understand the process so they can decide how mines will affect
their future.
Coming on this trip, actually, has really broadened my perspective and actually
raise my level confidence that it can be done in a much
safer manner. But I do believe certainly that,
especially the large mining companies or any miner actually or
anybody, they're in it for a profit and they're going to try and get the most they can.
I'm reassured by the level of responsibility that
more of them are taking now, albeit, they may have been forced to go there
in recent years. That's
part of the responsibility we have is to make them
hold up to that.