Initially, AC Sweepers used two regenerative air units to clean up the dust, but those units pushed the dust around rather than sucking it up. It soon became clear that it was necessary to use a unit that had a spray tank.
The dust, a non-toxic mixture of cornstarch and dye, was between 4-6 inches thick in some areas of the race route. Both ground crews and sweepers were required to properly clean the area of the Color Run.
The consistency of the dust was so fine that additional kick-up of material occurred from pedestrians and traffic.
A new phenomenon has swept the country — The Color Run. People are participating in a 5K race that explodes with colors at various check points along the route. As runners hit the check points volunteers throw a yellow, green, blue, purple or pink dust coating both the runner and the pavement.
Once the race is completed the area is left coated in a 3-4 inch layer of colored dust. The dust is a natural mixture of cornstarch and dye, and it is not harmful to the environment or water systems. Volunteers used one 50 pound bag of dust in each of the four zones totaling to 200 pounds of material. Despite the safety of the mixture, extensive cleanup is required.
The Color Run organization contracted AC Sweepers & Maintenance Inc. to complete the street cleanup after the Atlanta, GA, race this past April. The Color Run was AC Sweepers’ first experience working with such a fine material, and the consistency of the material both dry and wet posed several challenges. However, AC Sweepers crews were able to use trial and error to successfully complete the cleanup of the site.
The original cleanup plans organized by The Color Run called for AC Sweepers to sweep the roads while Southeast Site Services was contracted to complete the cleanup of miscellaneous waste items such as cups and paper.
Challenges of Dry Dust
First, Southeast Site Services tackled off-road. “The city of Atlanta was concerned with the color because aesthetically they didn’t want the color to remain on the grass and trees,” says Latasha Crenshaw, owner of AC Sweepers. “The ground crews used blowers to blow the dust off the sidewalk onto the street so the street sweeper could pick up the dust.”
As that was being done AC Sweepers began sweeping the streets of the high-traffic race route, where the fine dust was pushed around by passing vehicles.
“The dust was so fine that it resulted in additional kick-up of material from pedestrians and traffic,” Crenshaw says. Initially AC Sweepers used two regenerative air units, but the fineness of the dust and the use of gutter brooms kicked plumes of pink into the air and back onto the street and sidewalks.
So AC Sweepers switched to an Elgin Whirlwind unit, featuring an in-hopper dust control system. “When we didn’t use the water in the hopper the dust did kick up so having the water in the hopper helped minimize the kick-up that goes on,” Crenshaw says.
She says they used 300 gallons of water for the entire job.
Challenges of the WET dust
While sweeping the dust dry resulted in a high kick-up, sweeping the dust wet resulted in its own set of challenges. “When you use the water jets on the outside of the truck it created a worse situation because you’re picking up the colored liquid and it then bleeds into the asphalt,” Crenshaw says. “With a light rain, the material was even harder to cleanup because it stuck to the pavement.”
When water would hit the dust, it would turn into a Kool-Aid like river that would stain the gutter and pavement. “Because ground crews pressure washed the material it would just sit in the gutters,” Crenshaw says. “We had to continuously pressure wash the surface to push the material off of the streets.”
A water supply was unavailable onsite, so crews used truck-mounted pressure washers to complete the cleanup of the sidewalks, lawns and trees in the area. Using 25 people and four pressure washers, crews completed roughly 80 percent of the hand clean up for The Color Run.
“The subcontractor had its crews and a few pressure washers onsite until 10 p.m.,” Crenshaw says. “We came back at 8 a.m. on Sunday after completing our regularly scheduled routes. My crew swept the area from 11 a.m. until 4 p.m.”
Crenshaw says the hoppers only had to be dumped a few times because the material was so fine it didn’t take up much space. It was then disposed of in landfills. Cleaning the sweepers afterwards was fairly easy, but Crenshaw says they tried to blow the air filters clean but they were so dirty they just replaced them.
Despite the challenges that occurred during the cleanup of the Color Run in Atlanta, Crenshaw gracefully maneuvered through to successfully cleanup the area. The Color Run organization and Atlanta city officials were so pleased with AC Sweepers’ work that it received the cleaning contract for a second race in the Atlanta area.