If you see some balloons floating on the hill behind Graham Waste, don't think there is a sale on used cars. The balloons are part of the on-going Planning Board review process for two wind turbines with a proposed siting off Route 3A.

Beginning today (Friday) and continuing throughout the weekend, balloons will be floated as the approximate height of the two proposed wind turbine locations to aid the Planning Board in visualizing the scale of the project.

When the Planning Board discussed the possibility of raising balloons at the proposed siting of the turbines at their public hearing on Dec. 1, the plan was for two balloons to be floated on one tether (one to mark where the machinery hub of the turbine and the other to mark the high point of the turbine's blade).

After the meeting the applicant contacted the vendor who advised against placing two weather balloons on one tether. As a result, an alternate plan with what Planning Board chairman Al Moore expects to yield similar results has been developed.

"I don't think any of us (on the Planning Board) had first hand or even second hand knowledge of the type of balloons being used," said Moore. The Planning Board relies on their consulting engineer John Modzelewski to deal and advise on the technical aspects of each application before the board.

"I think he's come up with a scheme that will work perfectly fine," said Moore. "The one thing we are trying to see as a board is how the turbines will look from Route 3A, from Sanctuary Pond, from even the Common...this is a good way as a board to do that and at the same time give residents a chance to see it as well."

Here is the set-up for the balloons this weekend:

· The balloons will be raised from approximately 8:30a.m. to sunset on Friday, Saturday and Sunday, Dec. 12, 13 and 14. In the event of inclement weather on any of those days, the balloons will also be raised on Monday, Dec. 15.

· One balloon will be raised for each turbine.

· Each balloon will be a different color to distinguish the two turbine locations. The balloons will represent the maximum height reached by the turbine blades. The balloon will be between four and 10 feet in diameter depending on wind conditions at the time it is raised. The largest diameter balloon will be floated first and if unsuccessful (larger balloons tend to catch the wind and drift) successively smaller balloons will be floated. Each balloon will be a different color and will have a pink streamer attached to its base to aid in finding it.

· Below each balloon, orange six-to-10 foot streamers will be placed at the height of the nacelle, which is the machinery housing at the top of each wind turbine tower.

· A yellow streamer will be places at a lower elevation to represent the lowest point of the turbine blades.

· Below that, streamers about one foot long will be placed at intervals on the tether line from the lowest blade point to the ground.

Additionally, the balloon location will be monitored at approximate 10-minute intervals by the contractor. If wind conditions force the balloons more than 25 degrees off vertical, the balloons will be lowered temporarily and continuous attempts will be made to re-float them to their proposed location. At some point if conditions become too windy one would expect the work to be aborted.

Moore is hoping the weekend has decent weather to allow the Planning Board and the residents to see the balloons. While rain and clouds won't prevent the raising of the balloons, a blustery day will de-rail the endeavor.

A town-wide emergency notification call went out to all residences yesterday (Thursday) to let residents know the details of the plan.

Contact the Planning Board office at 781-383-3517 if you have any questions.