If conditions are favorable on the morning of Thursday, June 21, locals will be able to look to the skies above Mack Point to get an idea of how high a proposed 22.7-million-gallon liquefied petroleum gas storage tank would stand if it were built.

The balloon test, as it was referred to at the Monday, June 11, Searsport Planning Board meeting, is one of the many steps the project applicant, Colorado-based DCP Midstream, is undergoing as part of the company’s effort to satisfy requirements set forth in town ordinances.

Tuesday, June 19, company spokesperson Roz Elliott explained what the balloon test entails and what it might look like to locals and those passing through the area.

The test, which Elliott said is tentatively scheduled for Thursday morning, is intended to give a visual indication of not only how tall 137 feet is, but also how a 220-foot-wide tank might look against the skyline.

Elliott said a team of contracted experts set up at the site of the proposed development very early in the morning, at which time factors such as wind and fog are evaluated. If weather conditions are favorable, Elliott said, the exact center of the site — where the highest point of the tank would be located — will be the point from which a red balloon will rise to 137 feet.

The balloon, which Elliott said measures between six and seven feet across, will expand as it rises and is intended to be quite visible.

Once the central balloon has risen, Elliott said the next step is to use GPS units to log the coordinates showing where the sides of the tank would be located and then use four large yellow balloons to show the width of the tank.

“That’s so we’ll really know what we’re looking at,” said Elliott.

But the procedure is not without its complications, Elliott said.

“Fog and wind are not our friends as far as getting good results,” said Elliott, noting that gusts at five miles per hour or less are considered calm for the purposes of the test. “Often we have to come back several times to do this, and it can take up to five times.”

That’s because along with dealing with the weather, Elliott said, much of the parcel the company plans to construct the tank on is wooded, increasing the risk of damage to the balloons.

“Balloons don’t like sharp objects like pine needles, so we may have to do some finagling,” she said.

And there are several factors to consider even after the site has been prepared and the balloons are afloat. Part of the test includes the use of a high quality digital camera to capture images of the balloons from several viewpoints, and all photos must be snapped at a location of 80 degrees over the horizon to make sure the photos are consistent and offer the most accurate visual possible.

“We’ll have people stationed at those key coordinates monitoring the balloons,” said Elliott, adding that the entire team remains in close communication throughout the entire test, which she said will likely last between four and six hours if all goes as planned.

“Sometimes you have to wait 30 to 40 minutes,” said Elliott of the time between photographs.

The results of the test will then be reported to the Searsport Planning Board, Elliott said.

For those interested in viewing the balloon test, Elliott said it will take some time to establish coordinates and prepare the site, and the first balloon would not likely rise much before 8 a.m. Thursday morning and would be visible for much of the day.

“It’s a pretty involved exercise,” she said.

If weather conditions are not favorable Thursday morning, a backup test has been set for Friday morning, June 22.