- [Narrator] Mount Saint Helens is no secret
to those who like to climb and trek on its broad,
snowy slopes.
Especially on the mountain's south side,
it's easy to forget what this mountain is capable of,
unless you make a trip to the rim for a reminder.
This is as close as most people get,
to Mount Saint Helens' dangerous side.
An unfriendly, forbidding crater that's off-limits
to everybody.
Well, just about everybody.
After signing away our life in liability forms,
we were allowed to join the few scientists,
who do have permission to enter the crater.
But, we were warned.
- [Chris] You're going in an active volcano.
There could be steam explosions.
You're dealing with poisonous gas.
You're dealing with weather, I mean,
you're going into a harsh environment.
You're just a visitor, and hopefully you're welcomed.
- [Narrator] Our helicopter hovered briefly,
above the hundred foot high Loowit Falls,
before setting down on the north end of the crater.
- We're right I the blast.
Actually, we're right at the edge of the creator,
right here, and if it went off,
like it did in 1980, we wouldn't be alive to talk about it.
- [Narrator] Our only transportation out of here, flew off,
leaving us alone for the day,
and within minutes we got a taste of what passes for normal,
in this place.
- [Charlie] This is one reason
that it's closed to the public,
some of these rocks coming down are actually
as big as a Volkswagen.
And, a hard hat wouldn't do ya any good.
- [Narrator] Charlie Anderson led the way,
deeper into the crater.
He's an independent geologist and volcanologist.
He knows the dangers as well as anyone,
yet he still gets excited about coming here.
- In fact, this is my hundred and fortieth trip,
since 1980, and this sort of a disappointing year,
because I've only made it up here twice.
Normally I make it up here ten or twelve times a year.
- [Narrator] The other researchers are here
to help document the changes taking place
in this exotic, other-worldly landscape.
Travel here is extremely difficult.
There are no trails in the crater,
and the going is slow.
Up ahead is the volcanic dome, 1,000 feet high,
which has been growing in violent, and unpredictable
fits and starts, ever since the 1980 eruption.
- [Charlie] The last dome building event was actually
in October of 1986.
We had steam eruptions occur without any warning
between 1989 to 1991,
and I happened to be in the crater when one of those went,
and all I did was go behind a rock,
and just pray, and the thing shot out ash, and stuff,
about sixteen, seventeen thousand feet above the dome.
And, we were wondering if we'd ever walk out of that one,
ya know.
- [Narrator] Things are quieter today.
Everyone is cautiously wary,
yet eager to find out what lies ahead.
- [Chris] It's an adventure.
I can't pass it up being a geologist, I mean,
I have a volcano in my backyard, an active volcano.
- [Narrator] Chris Barrens has been with Charlie
on over 40 research trips to the crater.
- [Chris] There's about a cross-section
of approximately a 3,000 year history,
so just to read the historical part of past eruptions,
and present eruptions, to me as a geologist,
is extremely exciting.
- [Narrator] The question on every geologist's mind,
is when will this mountain erupt again?
Predicting that is the trickiest part of volcano science.
But, there are other changes taking place here,
that are worth understanding,
and possibly, worth worrying about.
One of the newest dangers,
is a glacier that straddles the dome.
That's much bigger than it first appears.
- These lines over here are crevasses.
Crevasses on a glacier show glacial movement,
and it's moving down the mountain, actually.
From September, 2002 to July, 2003,
the glacier advanced down the mountain 60 feet.
Which is incredible.
In July, 2003 there was approximately 80 feet more snow,
than there was last year at that time.
- [Narrator] Charlie was among the first to document
the glacier's formation,
and his research indicates that it's growing unusually fast.
- [Charlie] I don't think anybody in the world has seen
a glacier grow from almost the very first snowflake.
This is the fastest new glacier growing
in the continental United States.
While most glaciers are starting to recede on mountains,
because of global warming, this one keeps advancing.
One of the many reasons why this glacier is advancing,
and accumulating, it's on the north side of the mountain,
which has little sunlight,
so, the shadows keep the snow from melting.
- [Male Voice] Wow.
- [Narrator] A steady stream of dirt and rock,
also ends up scattered on the ice.
This layer of debris forms an insulating blanket,
that keeps the ice from melting,
and allows the glacier to build larger and larger everyday.
Glaciers, of course, aren't uncommon in the Cascades.
But, the rapid pace of this glacier's growth,
sets it apart from others in the northwest.
Just 50 miles away, is Mount Rainier,
a more typical Cascade peak,
with several dozen named glaciers sprawling down
the mountain's flanks.
Rainier's glaciers are well-known, expansive,
and visible from just about anywhere.
But, Rainier is a relatively inactive volcano,
and its glaciers are shrinking.
In contrast, the unnamed glacier on Saint Helens
is growing fast, and it's sitting on top
of a restless, and earthquake prone volcanic crater.
- [Chris] One of the dangers would be if the volcano
becomes active again.
There's a pretty good source within the crater itself,
of a lahar, ya know, a mudflow emanating from the crater,
if there's a significant eruption.
- [Narrator] It's happened before.
During the 1980 eruption,
the mountain top glaciers dissolved, joining rock
and other volcanic debris, to form a massive lahar,
that swept down the Toutle River valley.
This is not a scene residents want to see repeated.
At the USGS National Volcanic Laboratory,
in Vancouver, Washington, seismographs act
as an early warning system,
gathering realtime earthquake and tremor information,
from sensors placed on the mountain.
- [Steve] We're always monitoring Mount Saint Helens,
because it is the volcano that's erupted the most frequently
in the Cascades.
- [Narrator] Hydrologist, Steve Schilling says there
is reason to take notice of what's happening in the crater.
- [Steve] Because it erupted in 1980,
did not remove all hazard.
So I can show you, as comparison here between 1980 and 2000,
and so you can see as I flicker that on and off,
the dome grows and the increase within the crater,
sort of in a horseshoe shape around the dome,
of the snow, and ice, and rock that's accumulating,
and so that's a fairly quick period of time
for this glacier to develop.
Eventually what this will do, is fill up,
and in who knows how many years from now,
eventually we'll have a mountain like it looked
prior to the 1980 eruption.
And, it will erupt again, someday.
- [Narrator] Studying the glacier helps scientist calculate
how much ice, snow, and rock is accumulating.
And, whether something short of an eruption,
like a big earthquake, could cause a lahar,
is one of the things geologists want to find out.
But, the glacier is now big enough,
that a lahar, if it happens, will probably cause
considerable damage.
- This used to be almost flat, or let's say
a ten degree angle slope, if you take all that mass out,
going all around the dome, that's how much
has accumulated since 1986.
The lahar hazard would be tremendous,
because all the glaciers that were obliterated
in 1980, half of that mess is back in the crater, right now.
It would take five million dump trucks,
just to get all that snow mass out.
- [Narrator] The Toutle River valley still bears wounds
from a series of lahars in the 1980's.
The danger today is aggravated,
because the mountain's throat has been blasted wide open,
and only an aging sediment dam, miles down river,
stands in the way of the next debris flow.
This dam is filling up,
becoming less and less effective over time.
Things have been quiet for many years,
but the visible damage of past lahars,
serves as a reminder what the mountain that lies upriver
shouldn't be ignored.
Back in the crater, Charlie continues to document
the glacier's growth.
But, recent trips have evolved into explorations,
of the previously unknown, hidden world, of ice caves.
- [Charlie] There are actually 26 entrances, up here,
and there's a mile and three quarters of cave.
The caves are continuing to expand,
and sometimes they fall apart in different places,
as the glacier keeps creeping around.
- [Narrator] The caves conceal may hot spots in the crater,
and they shift and collapse,
and reshape constantly.
So, Charlie keeps his trips to the cave short.
- [Charlie] In the caves it's very dangerous,
because at certain times of the year, like in 1998
for example, we had 445 earthquakes in the month of August.
We're just basically studying to see how they're formed,
like is it geothermal activity,
and it is a lot of geothermal activity
for the fumaroles that are starting this cave.
- [Narrator] The caves are misted by steam,
and ground vents spew hot and sometimes poisonous gases.
Melting glacial ice joins these hidden fumaroles
and ground vents beneath the dome,
only to emerge as boiling streams,
that cascade down the mountain.
These thermal features provide clues about what the mountain
is up to, how active it is, how hot it is,
and what kind of changes are taking place from year-to-year.
- [Chris] This is a geothermal spring, or a hot spring.
And, here's a good example of the algae that grows in it.
The darker brown grows at a higher temperature,
and then you get the green,
which grows at a lower temperature.
The water at source,
is probably about 170 degrees fahrenheit.
- [Narrator] Scientists will continue
to monitor the mountain for increases in temperature,
as well as any up-ticks and tremor activity
that could trigger a lahar.
Yet, despite the abundance of strange geologic activity
in the crater, research suggests that the mountain
is in fact, cooler than it was twenty years ago,
and is slowly quieting down.
People like Charlie are just beginning
to put all this information together.
Still, there are reminders everywhere,
that this is new earth, and is a place where change,
even violent change, is a constant.
(crashing rock)
By late afternoon, a haze had filled the air,
caused by a near constant cascade of rock falls,
and avalanches.
Chris and Charlie agreed it was time to leave.
- [Chris] It's a risk, it's a calculated risk,
and that's part of the research, I mean,
ya know, if no one went into this type of environment,
no one would really know what was going on.
It's a needed thing to do.
- [Narrator] As we lifted off,
and looked down upon the crater from a safer distance,
we tried to pretend once again,
that Mount Saint Helens is the peaceful place
that many have come to think it is.
It's probably wiser to accept the fact, this it isn't.