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Concern about a pending eruption from Mt. Redoubt has cooled off a few degrees since Sunday when the volcano came rumbling back to life in the early morning hours.

Staff at the Alaska Volcano Observatory have reduced their initial warning that an eruption could be imminent within hours to a day, instead warning an eruption is possible within days.

They're continuing to remain vigilant of activity on the peak and a 24-hour watch is ongoing. The observatory did receive a number of calls Tuesday evening regarding Mt. Redoubt, but reported that seismic, radar and satellite data did not indicate an eruption.

"Seismicity is still above background levels, though it's not the same as it was a few days ago. We'll continue to be keeping a close eye on it," said Matt Haney, a seismologist with AVO.

On Tuesday, clear weather allowed a crew from AVO to conduct a second overflight of the peak to look for any physical changes and measure sulfur dioxide emissions.

Large holes in the snow cover had been melted near the summit and AVO posted several photos of steaming fumaroles, or vents in the side of the mountain.

Michelle Coombs, a geologist at AVO, said that measuring the rotten egg-smelling sulfuric gas, along with the far less offensive carbon dioxide being emitted from the mountain, can tell observers what's going un underneath the summit cone.

"Carbon dioxide and sulfur dioxide's main source is magma," Coombs said. "First of all their presence tells us there's magma at some depth, and the abundance of the gasses can tell how much and how deep it is."

A rise in the concentration of emissions could forewarn of a pending eruption.

Data collected on Tuesday however, appeared to be inconclusive. The information was sent to the Cascade Volcano Observatory in Vancouver, Wash., for further analysis.

Coombs said that a lack of wind made measurement of the plume difficult as the gasses were diffusing into the atmosphere.

"We definitely confirmed that there's sulfur dioxide, but that's maybe all we can say," Coombs said.

A second attempt later this week is in the works, and Coombs reported that a colleague from CVO is coming in with an instrument to measure carbon dioxide levels, too.

Coombs said scientists at the observatory have two theories as to what may be going on underneath the volcano.

One theory is simply that old magma from the 1989-90 eruption shifted, allowing gasses that were trapped beneath to suddenly begin escaping.

The second, and more likely theory in Coombs' opinion, is that there's been a new injection of magma.

Coombs explained that about 4 to 6 miles below the volcano is a magma reservoir.

"It's not just below surface waiting to erupt. Often these systems can get boosted from great depths to intermediate depths. From there it's very hard to tell if it will continue to rise to the surface," Coombs said.

The best bet for predicting an eruption will be the use of several seismometers located around the peak, recording every twitch the mountain makes and sending it back to AVO in real time.

Coombs said she and her collegues watch this information the closest as it offers them a better idea as to what the mountain will do.

The volcano's last eruption in December 1989 was preceded by a month-long or so period of steaming and increased earthquake activity, followed by a 23-hour period of elevated seismic activity before the first eruption.

The peak continued to erupt sporadically for a five-month period.

Coombs said the tremors recorded on the mountain now are often small and couldn't even be detected by a person standing on the mountain.

"The shaking we detect under Redoubt is significant to us, but very, very low level. Most events are magnitude 1," she said.

These pale in comparison to the 5.7-magnitude quake that rattled Southcentral on Saturday morning.

Coomb's said there was some speculation that the activity on Redoubt and Saturday's quake were related.

"Over the past few years we have realized that big earthquakes can shake things up under volcanoes, but usually that only happens with bigger earthquakes," she said.

She categorized the weekend shake-up as a mid-sized event, not likely to have had much effect on the mountain.

Crews were working on the mountain Tuesday to get a Web camera and a new seismometer up and operational. The two were initially going to be installed in mid-November, but foul weather curtailed that trip.

Coombs said she hoped the Webcam would be live on their Web site, http://www.avo.alaska.edu/webcam/ by Tuesday evening.

Should the volcano erupt, it won't spew magma like the volcanoes of Hawaii, but will instead inject ash into the atmosphere.

If the wind's blowing in the right direction this could make for a scenic view, however, if the wind directs the ash cloud toward the peninsula, residents can expect ashfall.

During its last eruption, some areas of the peninsula saw ash up to five millimeters deep.

For central peninsula residents monitoring the volcano's changing moods, Scott Walden, emergency management coordinator for the Kenai Peninsula Borough, urged people to monitor weather band radios, television or radio stations and to be prepared.

Walden said he and his staff were prepared for an eruption should one occur.

The borough would be in charge of notifying local emergency services in areas where ashfall would become a problem.

Additionally Walden recommended people visit the borough's emergency management Web site, http://www.borough.kenai.ak.us/emergency/default.htm, AVO's Web site, http://www.avo.alaska.edu/ and the National Oceanic and Atmospheric Administration site, pafc.arh.noaa.gov/volcano.php, for preparedness information.

He said the borough would receive immediate notification from AVO, the National Weather Service and the Department of Homeland Security if an eruption takes place.

"Our job would be to get info out to appropriate agencies and coordinate additional information," he said. "If it were to occur over an extended period of time we would coordinate an effort to get food and medications delivered to the peninsula in some manner."

Walden recommended that every home have a disaster kit prepared so that families or individuals could survive without normal services for three to seven days.

This doesn't mean just having food and water for that period, but other necessities such as medication and a means of keeping homes heated and lit should there be a disruption to power and gas.

Additionally, he recommended a few special precautions specifically for an eruption, such as keeping a supply of disposable particle masks on hand to avoid inhaling the fine dust. People with repertory illnesses should also consult with their physician if they haven't done so already.

Plastic sheeting for homes and extra air filters for cars are all also items best kept ready. Driving through an ash fall can be particular hazardous too.

"Ash is a slippery substance that can cause dangerous driving conditions," Walden said.

Walden was around for the last eruption series in 1989-90.

"We had white-out conditions at times. There were considerable amounts of accidents," he said.

He also advised pet owners not to forget about their four-legged friends.

"They need to put animals in a garage if they have one or get them inside. Owners with pets on medications need to consider having supply for them as well," Walden said.

In case of ashfall:

The following are recommended actions during and after an ashfall, from the Alaska Volcano Observatory pamphlet "Ash Alert":

During an Ashfall:

* Stay indoors, if possible;

* Close doors, windows and dampers;

* Avoid burning woodstoves or fireplaces;

* Eliminate draft sources;

* Do not run exhaust fans of clothes dryers;

* Listen to the radio;

* Vacuum furniture and carpets and try not to wipe, as ash will scratch;

* Brush, shake and presoak clothes then wash with plenty of detergent. Avoid soap as it will gum up;

* Cover and don't use computers, stereos or other sensitive equipment.

After an ashfall:

* Wear a respirator or breathing mask during ash cleanup;

* Use goggles for eye protection, especially if wearing contact lenses;

* Remove heavy accumulations of ash from roofs and rain gutters;

* When sweeping, dampen with water or sprinkle with "Industrial Sweep" to avoid raising dust unnecessarily.

For information on Mt. Redoubt and emergency preparedness, visit:

• Kenai Peninsula Borough Office of Emergency Management: http://www.borough.kenai.ak.us/emergency/default.htm;
• Alaska Volcano Observatory: http://www.avo.alaska.edu/; or
• National Oceanic and Atmospheric Administration ashfall information site: pafc.arh.noaa.gov/volcano.php

Dante Petri can be reached at dante.petri@peninsulaclarion.com.