The Clarke County School Board approved a contract modification Monday night to increase the use of pesticide treatment that will be used to control termites at the new school site. The $7200 change order submitted by the construction project general contractor, Shockey & Sons, was approved unanimously.
At last night’s Special School Board Construction meeting the School Board approved the treatment of the new building’s underslab with a “termicide” agent known as “Baseline”. The active ingredient in Baseline is bifenthrin. The underslab treatment is a discretionary increase over the previously approved school construction plan which only required that pesticide be sprayed around the periphery of the build.
Last night’s meeting did not include discussion of health or environmental considerations associated with the increased level of pesticide use. However, School Board member Jennifer Welliver (Berryville) did question whether there was enough wood in the school design to warrant the increased pesticide application.
Welliver’s question was not addressed during the discussion.
In a December 23, 2009 letter presented at last night’s meeting, Bruce Ryser, Product Development Manager for FMC Corporation stated “I was asked to provide assurance Baseline and Talstar P contain the same active ingredient. Baseline contains 23.7% bifenthrin, the active ingredient that protects against termites and other insects. It is a more concentrated formulation of bifenthrin and is typically mixed at one quart in 100 gallons of water.”
FMC Corporation of Philadelphia is the developer of the bifenthrin molecule. “Talstar P” has received attention recently as a pesticide used for killing the brown marmorated stink bug.
While the pesticide label for bifenthrin lists the chemical as “extremely toxic to fish and aquatic invertebrates”, not an issue at the new high school site, the label also contains cautions for “preventing siphonage of insecticide into water supplies” and cautions against contamination of cisterns and wells.
Clarke County’s karst topography makes groundwater particularly susceptible to surface contaminants.
Mz Bugz Termite Control, LLC of Kingsport, Tennessee, the contractor selected to treat the 134,000 square-foot underslab, said in a letter to Shockey & Sons that the treatment will be performed as specified in the label for bifenthrin by FMC. A separate $8600 proposal to Shockey & Sons from Winchester-based Barrett Pest & Termite Services to treat the site using “AggreZor 75 WSP” pesticide was rejected.
After the meeting Gannett Fleming’s construction manager for the project, Michael Castelli, said that the primary wooden structures being protected by the underslab pesticide are the gymnasium floor and the auditorium stage floor.
“The amount of wood in the building isn’t that much but the cost for the protection is relatively low” Castelli said.
Castelli said that the underslab treatment is usually based on the architect’s recommendation, in this case Crabtree Rohrbaugh & Associates.
“Some schools and facilities in the area use this approach, some don’t.” Castelli said. “Some architects recommend it and others don’t.”