CLEARFIELD — The Pennsylvania Department of Transportation (PennDOT) announced surface treatment operations, more commonly known as “oil and chip,” on two Elk County roads during the next two weeks.
The treatment seals the road surface to keep water out, restores the friction of the surface to enhance traction, and extends pavement life between resurfacings.
Starting Tuesday, May 21, PennDOT Elk County Maintenance crews will be engaged in surface treatment operations on Route 120 in the City of St. Marys to the Cameron County line. Flaggers in the roadway will provide traffic control during daylight hours during these operations. PennDOT anticipates these operations will continue through Thursday, May 23.
The following week, starting Tuesday, May 28, crews will begin operations on Route 255 between Johnsonburg and the City of St. Marys. PennDOT will reduce the speed limit within this work zone to 45 miles per hour. Reducing the speed limit will reduce the time it takes for the stones to fully adhere to the hardened asphalt and help prevent oil and chips from coming free of the roadway. Flaggers in the roadway will again provide traffic control during daylight hours.
PennDOT typically employs surface treatments as a preservation strategy on roads with low traffic volumes and speed limits of 35 mph or slower. This activity extends the life of those roads by keeping water out, which mitigates the damage caused by the freeze-thaw cycle of Pennsylvania winters and delays the formation of potholes and the oxidation process.
In recent years, PennDOT District 2 has expanded its use of seal coating to roadways with higher traffic volumes and speed limits of 55 mph or faster as it strives to effectively manage and preserve its assets while being good stewards of taxpayer money.
PennDOT performs this activity in temperatures greater than 60 degrees, generally between April and September. Crews begin by sweeping the roadway clean of debris. Next, they apply emulsion oil and a layer of stone, which they then press into place using a roller. Once cured, crews sweep any loose material from the roadway.
Generally, it takes about two days for the stones to bond to the hardened asphalt. PennDOT urges drivers to reduce their speed on roads that have received this treatment during the two-day curing period or to consider alternate routes.
