One week after cement dust covered patios, lawns and cars in a McKinney neighborhood, state officials said they are still investigating the cause. Officials confirmed it was cement dust released from concrete plant Martin Marietta, located along SH 5 in McKinney, sometime between July 18 and July 19. Much of the dust released fell in the McKinney Greens neighborhood located across from Martin Marietta. For years, residents in the area have expressed concerns about dust and noise coming from Martin Marietta and two other industrial plants along Hwy. 5. Texas Commission on Environmental Quality officials said they have not received information from the plant that details how much was released on July 18 and July 19. TCEQ regulates what is called particulate matter that gets released from the plant. “Based on the information the TCEQ [Dallas-Fort Worth] Region has received to date, cement dust was released from one of the silos at Martin Marietta,” spokesperson Marty Otero said in an email to Community Impact Newspaper on July 26. Because cement dust is corrosive, people should avoid direct contact with it, according to TCEQ’s Toxicology, Risk Assessment and Research Division. According to an email from TCEQ, “Once the dust is removed, this event is not expected to represent a long-term concern.” McKinney Greens resident Don Pizarro said cleaning crews came to his home July 26 and an additional crew is scheduled to clean his property July 31. Pizarro said there were 11 people cleaning the interior of his home. Crews also power-washed the exterior of his home, washed the windows twice and provided him with coupons for a car wash, he said. Pizarro said this is a 24-hour issue in his neighborhood because when the wind blows, cement dust from the trees and nearby golf course fall on residential properties. A spokesperson for Martin Marietta said TCEQ visited the ready-mix concrete plant July 19, and operations at the facility will remain closed until a cause is determined. The investigation is ongoing as of July 26. “We will work with the TCEQ to investigate what happened,” Amanda Miller, director of government affairs and public relations for Martin Marietta, said in an email on July 19. “Additionally, Martin Marietta has retained a company to clean up the material that was released, and the plant will remain shut down until we can determine the cause of this release and remediate it.” Additional comment from Martin Marietta was not available. Michael Quint, McKinney’s executive director of development services, said the city is working with Martin Marietta and TCEQ. He said information from TCEQ will not be available until the state entity’s investigation is complete, however, there is no timeline for completion. Residents are encouraged to visit www.mckinneytexas.org/1990/concrete-batch-plants for more information. Community Impact Newspaper will continue to update this story as more information becomes available.  Editor's note: This article has been updated to include additional comment from a McKinney Greens resident.