In the 1970s, Newark Airport buried coal fly ash beneath runways built for jumbo jets; more than 20 years later, FHWA said the pavement was still performing well

AI-generated representative image showing a stabilized fly-ash base being constructed. Credits – GeminiThe pavement must withstand repeated loads without failing or deforming when airports construct runways for huge planes. Throughout the 1970s, Newark International Airport in New Jersey hosted one of the biggest US operations using coal fly ash in a stabilised pavement base.