Dangers can come from Mt. Rainier even without an eruption. By looking at the map you can see
that this volcano has caused many lahars over time. Today the volcano is showing signs of activity.
Acid water has turned the upper slopes of the volcano into clay making them as risk for slope failure
and causing a lahare as the glaciers melt. The city you are concerned with is Orting. Orting is in
danger from both small and large lahars. The blue lines are rivers and streams. To determine the
distance you must measure the actual length of the stream. Start at the red star in the center of Mt.
Rainier and measure to the star at Orting
1. What is the distance from the top of Mt. Rainier to Orting along the Payallup river (starting
at the center of the cone marked by a red star burst and measuring the branch marked
by the arrows)?
2. If a lahar travels at 20 miles/ hour how much time does Orting have to evacuate? (Divide
the distance from 13 by 20 miles/hour = number of hours).
3. If a pyroclastic flow can travel at speeds of 100 mph how many minutes do the people at
Paradise have to escape from danger?
4. How many minutes do the people at Sunset have to escape from danger?
.
Dangers can come from Mt. Rainier even without an eruption. B.docx
1. Dangers can come from Mt. Rainier even without an eruption.
By looking at the map you can see
that this volcano has caused many lahars over time. Today the
volcano is showing signs of activity.
Acid water has turned the upper slopes of the volcano into clay
making them as risk for slope failure
and causing a lahare as the glaciers melt. The city you are
concerned with is Orting. Orting is in
danger from both small and large lahars. The blue lines are
rivers and streams. To determine the
distance you must measure the actual length of the stream. Start
at the red star in the center of Mt.
Rainier and measure to the star at Orting
1. What is the distance from the top of Mt. Rainier to Orting
along the Payallup river (starting
at the center of the cone marked by a red star burst and
measuring the branch marked
by the arrows)?
2. If a lahar travels at 20 miles/ hour how much time does
Orting have to evacuate? (Divide
the distance from 13 by 20 miles/hour = number of hours).
2. 3. If a pyroclastic flow can travel at speeds of 100 mph how
many minutes do the people at
Paradise have to escape from danger?
4. How many minutes do the people at Sunset have to escape
from danger?
