The state departments of Ecology and Health and The Boeing Co. sank test wells in 2011 to determine whether a dangerous chemical solvent the Boeing-Auburn plant near Algona used decades ago had escaped the property and seeped into the local groundwater.

State officials told the mayors of Algona, Pacific and Auburn they would release the results last March.

But 11 months passed from that promised release date before the DOE informed the City of Algona and its residents about what those tests had revealed.

And when Algona residents found out last month after a local radio station got on the story, they were not happy.

The toxin is trichloroethylene, or TCE, a chlorinated hydrocarbon commonly used as an industrial solvent. The Boeing Co. used it in the 1960s, ’70s and ’80s to degrease and clean airplane parts.

Given that TCE is known to cause cancer after prolonged exposure, Algona residents demanded answers about the safety of their drinking water.

Larry Altose, a DOE spokesman, explained what the tests revealed.

“What we know is that there is contaminated groundwater that originates on Boeing-Auburn property,” Altose said. “What we’ve been working on for a year now is to determine how far that goes. The most recent finding is that this plume of contaminated groundwater extends outside of Boeing property. We don’t know where the plume ends, we know it begins on the property. When we find out where it ends, we can begin cleanup.”

Altose maintains that there is nothing to worry about. One reason is that feet of impermeable clay and rock, laid down during the Oceola mudflow off Mount Rainier 5,700 years ago, separates the groundwater from the aquifers that supply Algona’s drinking water.

“This plume does not affect and is nowhere near public drinking water systems in the area,” Altose said. “In fact, it is moving in a direction away from the wells.”

In December 2011, the state and Boeing informed the mayors of Pacific, Algona and Auburn about the testing.

It drilled test wells throughout the area

But it never told residents what they were.

Richard Hildreth, former mayor of Pacific, said the dearth of information gave people the impression that the state had something to hide.

“All three of the mayors of Auburn, Pacific and Algona wanted to make sure this information did get out and that we had complete information,” Hildreth said. “We wanted to make sure that Ecology and Health and Boeing worked with our cities public information officers to make sure information got out so it wouldn’t create fear.”

That didn’t happen.

Altose agreed that the state should have gotten the information out sooner.

“We accept responsibility for that, we apologize to the community, and we hope that from here on out we will be able to get people the information they need about the investigation,” Altose said.

Hildreth said he believes the risk of contamination is minuscule.

“I think the risk of contamination of our drinking water is probably 1-in-10 million, I think it’s a very minimal risk, because of the barrier between those ground layers,” Hildreth said.

Now all anybody can do is wait for the next tests. The next round of drilling in that part of Algona is set for middle or late March.

“At the time of the meeting in December of 2011, there were about 65 wells that were either already in place or planned. Now I guess it’s over 250 wells, and they actually want to install another 150, 160 of them,” Hildreth said.

One big unknown is whether toxic vapors could rise to the surface. To date, testing at the Auburn Valley YMCA next to Boeing and nearby buildings hasn’t turned up any contamination.