Updated, March 23: The application of street sealant in Sun City remains suspended. Transportation Department staff are working with the product manufacturer to identify the reasons for tracking in recent applications. The street sealant product is used to fill small cracks and prevent oxidation of the road surface to extend the pavement life.
Transportation Department crews along with Ergon, the product manufacturer, are conducting tests in a vacant subdivision near Interstate 35 to help identify issues leading to the product’s tracking.
The recent tracking of the sealant in Sun City is the result of the latest applications not performing as they have in the past. Tracking is occurring mostly on warm days as the pavement temperatures reach 100 degrees. Staff have shared this issue with Ergon and requested a plan of action to prevent further tracking. Ergon’s recommendation is to apply and roll in dry “blotter sand” to prevent tracking. The sand should adhere to the remaining surface and provide a barrier between the surface and tires. The City’s contract engineer has suggested following a typical TxDOT maintenance procedure for applying the sand. It shall be applied with a truck-mounted sand spreader and rolled in with a pneumatic roller. Once rolled, the sand will be immediately picked up using the City’s vacuum sweeper. A black sand will be utilized to blend with the existing road surface. This application should be performed during the warm part of the day when “bleeding” is active. Staff performed this procedure on a small area with promising results.
Staff have prepared the necessary equipment to implement the manufacturer’s suggestions as specified. The weather forecast for the next seven to 10 days is not predicting the warm conditions that caused the bleeding over the past two weeks. Tracking has subsided somewhat and staff expects the product to continue to harden and cure in the upcoming cooler days. Staff continues to monitor the pavement conditions. When warm temperatures return, crews will be ready to implement the sanding procedure if necessary starting in the most egregious areas first. All asphalt roadways transfer some level of material as they are petroleum based. To minimize tire rubber and product tracking, residents should refrain from sharp turns into and on driveways.
Staff have been successfully removing the product from driveways upon request for the past three weeks. To prevent possible damage, requests for repeated additional cleaning will be deferred until the product has stabilized and tracking has stopped. Touch-ups also will be deferred until the product tracking issues are identified and corrected.
No further street sealant applications are scheduled at this time.