tonight, volcanos come to life. we remember the deadliest volcanic event in the history of the unite. a look back at the eruption of mount st. helens. and many said mount lasen was an extinct volcano that's until it erupted.

good evening, welcome to second look, i'm julie haener. california is nope as volcano country. one of america's most famous volcanos roars with fury day in and day out. the u.s. revealed these images of the volcanic eruption of hawaii's kilamangero. on the ring of fire in indonesia, a deadly eruption claimed the lives of 15 people in february. those killed would not outrun the sering debris that poured. more than 30,000 people had been evacuated from local villages as the volcano

rumblings grew larger. california has seven volcanos but that the usgs considers high risk. one of those is mount shasta which reaches 10,000 feet into the sky. part of the cascade ring, the last time mount shasta had a significant outburst. >> reporter: mount st. helens the wild child of the cascades remains the youngest, most active volcano in the southwest. the gaping wound from its eruption still sees raw. steam sizzling up from the hot rocks inside the crater an unmistakable arounding that it will roar to life again.

the mountains once forested flags with barren. and for miles, steam and volcano ashes slammed them down that morning. here with an inspiring view of mount st. helens, bob andrew points out details of the eruption that almost killed him. >> we heard nothing, we felt nothing. we were too close. that's the strange thing about it. we're just barely out of the blast zone. >> reporter: but andrew and a bus full of choir singers saw this. the mountain blew itself apart after weeks of rumbling and groaning. an avalanche of rock roared across 150 miles. it was the biggest landslide in all of recorded human history. a slurry of rocks snow melt and debris thundered across the melt. 57 people died. the avalanche buried dozens of

homes, the spirit lake lodge and the harry trueman who refused to evacuate. and a huge black plume blackened the sky. >> this plume is full of black ash and it is loaded with electricity. and the lightning storm is awesome. andrew and companions just beat the debris. >> people were killed 17 miles from the mountain. nearest i can figure it was at 27. yeah it was close. >> reporter: the blink of an eye everything changed. >> when i mean everything, that included our jobs. >> reporter: mickey was working on trails just outside the blast zone. >> it's quite a lesson that it provides us and a legacy as well. >> reporter: today he leads tours across the debris the volcano belched out here. these mounds of ash and rock are an outstanding 300 feet

deep. stretches 15 miles along the river. hundreds of people fled the volcano 20 years ago and life was never again the same. >> for some it was pretty, pretty catastrophic for them. i know some people that live here in this community and surrounding communities and never returned. >> reporter: but life has returned. willow and cotton wood trees now sprout among the rocky dunes. seeds protected under logs and nourished by the deep volcanic ash sprung to life. somehow surviving, adapting to a hard scrabble life across the sea. >> you will see the trees layed down and running away from the volcano. >> volcinologist says mount st.

helens continues to earn respect. after all, steam sizzling from a rocky dome thrust up from the molten magna below and earthquakes still rattling this mountain. the volcano is very much align deep low. >> we have evidence that sometimes it erupts at least intermittently for a series of centuries. so there's all the evidence that it's going to erupt again. >> reporter: but when? next week or next century, scientists don't know. this dam is designed to stop the landslide. the debris is much than buried across the path. >> change is going to occur. it's just a matter of how we as man deal with that change. >> reporter: perhaps several

human lifetimes from now, nature will have repopulated this volcano sculpted valley bringing in dense stance of native fir. >> the plan did not work. it didn't work for man's advantage but we've learned after 20 years that there has been some advantages of it. >> reporter: youngsters too kwroupg -- young to remember the eruption play soccer on the ash. and you can still hear folks measure time from the volcano. >> it was awesome then the devastation was awesome too. you cannot believe what it did to the river. the trees fell down like toothpicks. >> reporter: but there's a threat of hope here for those who have seen it through. the eruption, the death, the destruction, the heart --

hardship then the bursting of life from the ashes. >> 1600 elk, a couple of hundred coyotes, black bear, everything is back. that's the amazing thing. the recovery here in 20 years is just astounding. >> it is also humbling that on nature's scale, human prevail scales in the cycle of life destruction and renewal and experts say mount st. helens will do this all over again. >> since 1980, mount st. helens has stirred several time. the most recent when the volcano sent an ash of steam up into the sky. at that time geologists were concerned a larger eruption

would happen but it hasn 't. three men lose their lives on a california mountain. the silent dangers of a sleeping volcano. ♪

take the nestea plunge. nothing refreshes like nestea. a broader mix of energies, world needs which is why we are supplying natural gas, to generate cleaner electricity, that has around 50% fewer co2 emissions than coal. and why with our partner in brazil, we are producing a biofuel made from renewable sugarcane to fuel cars. let's broaden the world's energy mix, let's go.

welcome back to a second look. tonight the power of volcanos. to look at mount lasen it's hard to imagine nature's violence as it erupted. it was the largest eruption in california's recorded history. in 2001, bob mackenzie visited mount lasen and filed this report. >> even at the height of the summer vacation season, lasen park is a quiet place. the mountain rules in majestic silence at 2,000 feet overlooking its kingdom of lesser mountains, lakes and valleys. the silence is broken by the occasional vehicle. or by the hiss and rumble of

geothermal smelling of sulfur. or a meadow full of wild flowers. where you can sit in sunshine and look and listen. yes a quiet uncrowded place. but 87 years ago the silence was abruptly broken. gas, lava, boiling mud and steam came roaring from the mountain top. geologists knew that a volcanic eruption formed mount lasen about 27 years ago. an amateur photographer saw the volcano blow, grabbed his equipment, stood his ground and took these images. the eruption was not the first

odd phenomenon, for a full year the mountain had been emitting blasts of steam. and hikers had been hiking to the top. thankfully there were no hikers on the summit when the old volcano blew its top. buildings were lost but no lives. eruption formed ominous clouds. throughout the park you can see and smell the evidence of more hot stuff down below. >> as the volcinologist say there's going to be more eruptions in the future. we just don't know if it's in our lifetime or geological lifetime. if you look at all the

volcanos, which every mountain is a volcano or part of a volcano. it is a large history of eruptions over thousands of years. >> a generation saw what a volcano could do. mount st. helens exploded sending down a deadly coldirn and lava that sent hundreds hurrying to safety. abandoning vacation homes that would vanish in ashes and volcanic rock. there's news of its spread in the following weeks and months. and picnicking families would gather at what they considered a safe distance and watched the

show. and the mountain obliged them with eruptions throughout the day. and lasen became a national park. today's tourists come for the views, the wild flowers, the clouds that look close enough to touch, the lake, the camping and hiking and fishing. >> we first came through here, the devastated area up there was actually devastate. there wasn't any trees. it was just very small brush and you could see all the way to the mountain. now it's forest. so we've seen a tremendous change in this place in the last 40 years. >> it's not as popular as other parks like yosemite. you never see any crowd here. >> no it's always been, i would say the complaint of the forest service that nobody ever seems to come out here. it seems to be a lost attraction for the forest

service. it's one of the attractions that brings us up here. we have been at yosemite and had to fight the crowds on the valley floor, that's not for us anymore. >> reporter: the ground has been moving and shifts and blowing right from the beginningful usually it happens slowly and we don't notice. every now and then it happens in a big hurry and then we notice. when we come back on a sec look, how pitching a tent on a sleeping volcano could be dangerous. and bubbling natural coldrin causing havoc for hundreds of thousands of people in california. we'll visit the geysers in sonoma county. did you remember to pay the dog sitter?

yeah, citi mobile. and deposit that check? citi mobile. pack your bathing suit? wearing it. niiice bank from almost anywhere with the citi mobile app.

spewing lava and volcanish ash are the biggest display. volcanos can emit dangerous

gases. two ski patrollers at mammoth mountain tried to steep off a vent covered in snow. as they were working the snow collapsed. the men fell 21 feet into the vent filled with carbon dioxide and hydrogen sulfite. a man saw the men fall and he tried to rescue them. but he was overcome by the fumes. all three died. >> the first patrollers were overcome quickly within a minute or two. they were conversant upon falling and landing and asking for help. and then were silent within a minute or two. >> reporter: seven other ski patrollers became ill as they responded to the tragedy. it turned out that oxygen masks used by the ski patrol did not

seal out the poisonous gas. as craig heaps first reported in 1985 the carbon dioxide does not typically pose a problem unless they pitch their tent in the wrong place. >> reporter: in the midst of incredible scenic beauty, thousands of dead trees form an ugly scar on one of california's most popular tourist areas mammoth mountain. >> when we first saw it we thought it was a fire or something. >> reporter: carbon dioxide killed these trees covering 35 to 100 acres. mammoth is a 30,000-year-old volcano lying 30,000 miles east of san francisco on the far edge of the nevada. it last erupted 45 years ago. the gas comes from magna material boiling 30 miles under ground. in 1989 the magma sent a hot sering spike within two miles of the surface. that's when the trees started

dying. >> this material loses gas as it gets closer to the surface of the ground and the primary gas is carbon dioxide. >> reporter: scientists have measured concentrations of carbon dioxides in the soil here about 30%. when they find such a high level of carbon dioxide that's what kills the tree. odorless and colorless carbon dioxide poses little health danger to tourists in the open breezes here. however if it collects in a cabin or tent, c02 can be dangerous. as rictor found out when he took re -- refuge in this cabin. >> and i had some what of a difficult time getting out of the cabin. >> reporter: the forest service closed this campground but after concluding the health danger as insignificant will reopen it next summer.

but the under ground activity does raise the question, is mammoth about to erupt again. >> we could have an eruption here in a year or two or it could be thousands of years before anything ever happens. >> it doesn't bother us, we live in southern california. we're used to earthquakes and all kinds of natural disasters. >> reporter: most viewers say they find the view more frightening. when we come back on a second look, one of the world's largest geothermal fields is spewing steam. heat shields are compromised. we have multiple failures.

what's that alarm? fuel cell two is down. i'm going to have to guide her in manually. this is very exciting. but i'm at my stop. come again? i'm watching this on the train. it's so hard to leave. good luck with everything. watch tv virtually anywhere with the u-verse tv app. with at&t, the u-verse revolves around you.

welcome back to a second look. harnessing the power of volcanos. pg & e is doing just that to create electricity for 600,000

homes across the state. rob roth visited the world's largest geothermal field near sonoma. >> reporter: the ground bubbles, storms and snarling. but mostly it steams. welcome to the geysers where a rare subterrenial boiling room is helping to produce energy. >> it's one of the cleanest energies that can be produced. the only thing that is cleaner than geothermal might be hydroelectric or solar. >> reporter: the areas near a dormant volcanic field around clear lake. the energy producing process begins underneath these pits about five miles down where water comes in contact with scorching hot rock.

>> what's happening under ground is the magma from the center of the earth is heating the rock that is underneath the reservoir. in the reservoir there's natural waters that have been there for years that are heated and are boiled down in the reservoir. when we drill a well, the steam comes up under pressure up through the well at about 300 pounds per square inch and about 400 degrees farenheit. >> reporter: enough to power 850,000 homes or all of san francisco and berkeley combined. once the steam is spent most of it evaluates but about 1/4 of its condenses into water and then injects into deep wells of reservoirs where it once came.

what makes the geysers unique that produces steam. the geothermal plant can produce more power in california all they need is more water. there's additional water coming from a most unusual source. here in the town of windsor just north of santa rosa work crews are completing mile nine of a 41-mile pipeline that will run from santa rosa to the geysers. when it's completed, officials estimate about a year and a half, that pipe will carry sewage from most of sonoma county. pipelines will pipe that into the wells and it will come back as geothermal energy. >> how do we use that water more than once. we have water we've used it once, we've cleaned it up can we do something else with it.

this is what we're doing. it's a win for the city and a win for the environment. and a win for the energy situation in our state. and i don't see anything but positive impacts from this. >> reporter: especially because with all the steam production, cal pine says the under ground water supply is beginning to run low. no water, no steam. the sewage water from the pipeline will produce 85 mega watts of power. lake county already pipes its waste water to the geysers. and that's it for this week's second look. i'm julie haener, thank you for watching. we had to take just a little bit for the kitchen. because your kitchen dreams can be big. ikea has it all.

woah, this kitchen is beautiful! give him the tour. let me show you! soft-close drawers, farm sink! um... where's my room? we had to take just a little bit for the kitchen. because your kitchen dreams can be big. ikea has it all.

oh, hey, stuart, i got you a little souvenir from my trip to space. well, howard, that's very nice of you. yeah, maybe. open it first. it's my official nasa portrait. "to stuart, your comic book store is out of this world. just like the guy in this picture was." for the record, he also thinks the walgreens and the dry cleaners are out of this world. that's not true. at the walgreens, i was "over the moon" for their store-brand antacids. hey, stuart, i see you're getting ready for your halloween party. yeah, it's my annual attempt to meet women. ninth time's the charm. would you like me to help? i do have a certain je ne sais quois when it comes to soirees.