what was the damage?
It created some temporary major problems with transportation, sewage disposal, and water treatment systems, fine ash caused short circuits in electrical transformers, which in turn caused power blackouts.
1980 eruption of Mount St. Helens
The ash fall created some temporary major problems with transportation, sewage disposal, and water treatment systems. Visibility was greatly decreased during the ash fall, closing many highways and roads. Interstate 90 from Seattle to Spokane was closed for a week and a half. Air travel was disrupted for between a few days and two weeks, as several airports in eastern Washington shut down because of ash accumulation and poor visibility. Over a thousand commercial flights were cancelled following airport closures. Fine-grained, gritty ash caused substantial problems for internal combustion engines and other mechanical and electrical equipment. The ash contaminated oil systems and clogged air filters, and scratched moving surfaces. Fine ash caused short circuits in electrical transformers, which in turn caused power blackouts.
what happened after the mt st helens eruption An earthquake which caused the entire weakened north face to slide away, creating the largest landslide recorded when was the last time it erupted? January 2008 and before that? October 2004 and before that? Between 1980s to 1991 which was the deadliest eruption? March 27, 1980 eruptions describe the build up of this eruption that you just mentioned On March 20, at 3:45 p.m. Pacific Standard Time, a shallow magnitude 4.2 earthquake centered below the volcano's north flank, signaled the volcano's return from 123 years of hibernation. A gradually building earthquake swarm saturated area seismographs and started to climax at about noon on March 25, reaching peak levels in the next two days, including an earthquake registering 5.1 on the Richter scale. A total of 174 shocks of magnitude 2.6 or greater were recorded during those two days how far did the landslide reach? He traveled and moved across Spirit Lake's west arm, part of it hit a ridge about north, some of the slide spilled over the ridge, but most of it moved down the North Fork Toutle River, filling its valley up to deep with avalanche debris were there mudslides as well? Yes, mudflows from the southern and eastern flanks had the consistency of wet concrete as they raced down Muddy River, Pine Creek and Smith Creek to their confluence at the Lewis River is it true there were side way blasts? Yes what were the effects? 57 people known to have died in that day's eruption succumbed to asphyxiation, while several died from burns how large was the ash column? A huge ash column grew to a height of above the expanding crater in less than 10 minutes and spread tephra into the stratosphere for 10 straight hours what properties does ash have? The ash properties have large variations due to meteorological conditions describe its chemical composition Approximately 65% silicon dioxide, 18% aluminium oxide, 5% ferric oxide, 4% each calcium oxide and sodium oxide and 2% magnesium oxide, alone with some trace chemicals  0.05–0.09% chlorine, 0.02–0.03% fluorine, and 0.09–0.3% sulfur how many people died? 57
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1980 eruption of Mount St. Helens [SEP] Ash damage and removal
The ash fall created some temporary major problems with transportation, sewage disposal, and water treatment systems. Visibility was greatly decreased during the ash fall, closing many highways and roads. Interstate 90 from Seattle to Spokane was closed for a week and a half. Air travel was disrupted for between a few days and two weeks, as several airports in eastern Washington shut down because of ash accumulation and poor visibility. Over a thousand commercial flights were cancelled following airport closures. Fine-grained, gritty ash caused substantial problems for internal combustion engines and other mechanical and electrical equipment. The ash contaminated oil systems and clogged air filters, and scratched moving surfaces.