Here's what we know, and don't know, about the explosion at the Eagle construction company

EAGLE - More than a day since a fire destroyed an industrial building in the town of Eagle, some questions remain as fire officials sort through the steel rubble.

Not all the answers are readily at hand, though the reasons why are also telling in and of themselves. Simply, officials and the business itself are still trying to find their way to firm conclusions.

Summerset Marine Construction, W357 S8715 Chapman Lane, was consumed by the fire, which set off multiple explosions, injuring three workers and resulting in injuries to three firefighters, who fought the blaze throughout the day Thursday.

Here are five lingering questions and what is known to date:

What was the cause of the fire that set off the explosions?

Fire officials still don't know. A final answer is at least a week away. But from witnesses and other unofficial accounts, the fire started in the welding bay while work was being done.

In an afternoon news conference Thursday, Matthew Haerter, the assistant chief of the Western Lakes Fire Department who spoke as a member of the Southeastern Wisconsin Incident Management Team, seem to rule out the idea of spontaneous combustion. That would suggest the fire more likely started during normal welding operations.

Again, how exactly is still under investigation, which was delayed Thursday by the task of putting out the flames. Excavators began working on the site late Thursday.

"The structure of the building has collapsed significantly and trapped a lot of the combustibles that are burning underneath a very thick metal roof," Haerter said. "There is a line of how far do you go for extinguishment versus how long do you wait to be able to get investigators to get an eye on (the damaged building) before it is disturbed."

Alcohol Tobacco, Firearms, and Explosives agents were among the investigators on the scene to try to pin down the cause of the explosions, Haerter added.

The Kettle Moraine Fire District is the lead investigator.

How much water was used and why did it have to be trucked in?

The 30 tanker trucks, some from as far away as Kenosha County, were used to transport water to the fire scene.

Through 1:30 p.m., roughly six hours after the fire started, about 400,000 gallons of water — drawn from two area lakes and fire hydrants in the villages of Eagle and Mukwonago — had flowed onto the fire, officials said. Each water tender on the back of the trucks holds about 3,000 gallons.

No fire hydrants were available in the business park itself. Given the rural nature of the town, that's hardly a surprise, officials noted.

"It's not something that people think of very often, but the vast majority of the United States does not have fire hydrants, except in major cities," Haerter said. "The vast majority of fire departments cover rural areas, and those rural areas typically have the necessity to have the water brought to the fire."

What will happen to Summerset Marine Construction?

Summerset Marine Construction's 24,000-square-foot Eagle facility served as a showroom, office, factory and warehouse, making, selling, installing and servicing waterfront piers.

The damage has sidelined those operations of the 32-year-old company for now, though a greeting message on the company's Eagle facility phone line indicated the business was still functioning.

Larry Chapman, Summerset's owner, was not immediately available to comment for more information about how his business will continue to service customers. But in a news conference Thursday, he pledged to do so.

"We're going to get through this," he said. "It's a tough time for our company, but we'll buckle down, persevere and make sure people can provide for their families, and we'll take care of our customers."

Summerset's territory includes all of Waukesha County's lake country as well as lakes in Walworth County, according to the company's website.

What will happen to the dozens of employees who work there?

It's unclear exactly how many of the company's estimated 80 workers will be idled by the fire. However, not all workers were dependent on the Eagle building.

Because the company is involved in sales for three brands and does onsite installation and service work along lakefronts, not all employees have been left without timely tasks as boats take to the lakes this spring.

"We are working diligently to serve our customers to the best of our ability and we are on the lakes working away," an updated greeting message on the company's Eagle facility phone line said.

Who else was affected by the fire, and was the community in danger?

Three workers and three firefighters needed varying levels of medical attention Thursday. One, who Chapman described as a "young worker," required surgery to repair a broken femur sustained during the incident.

Beyond that, the fire caused inconveniences for others, making the disaster a communitywide concern throughout the entire day. But there were few actual dangers to residents and nearby businesses.

Fire officials evacuated businesses along Godfrey and Chapman lanes as a safety precaution. But by early afternoon, the fire was considered sufficiently contained to no longer be a threat to other property.

However, the sheer amount of smoke — which early in the fire could be seen from miles away — caused enough of a concern to prompt public safety officials to order residents within a one-mile area of the site to shelter indoors, keeping the windows off and the air-conditioners off to keep the smoke out.

There was no issue with hazardous materials or toxins, Haerter explained, given that the burning combustibles were typical to what is normally found in fires.

Students and staff at Eagle Elementary School were also evacuated to Palmyra Middle and High School as a precaution due to the elementary school’s proximity to the Summerset plant. School was back in session Friday.

Contact Jim Riccioli at (262) 446-6635 or Follow him on Twitter at @jariccioli.

Our subscribers make this reporting possible. Please consider supporting local journalism by subscribing to the Journal Sentinel at

DOWNLOAD THE APP: Get the latest news, sports and more

This article originally appeared on Milwaukee Journal Sentinel: Summerset Marine Construction explosion: What we know