A rubbish dump known as the “Rainham Volcano” where waste has been constantly burning for years has been declared contaminated.
Firefighters have been called to the site in east London 160 times in the last three years as blazes flare up.
Thick black smoke is also regularly visible from the site on Arnolds Field in Launders Lane, Rainham.
Havering Council has now officially declared the dump a contaminated area following a judicial review.
The Clean Air in Havering group brought a legal challenge against the council over the site, leading to it being redesignated under the Environmental Protection Act.
Residents have previously complained that the site has caused them to develop breathing problems and coughing fits, while local GPs have blamed high levels of respiratory and lung diseases in the area on the site.
The declaration that it is contaminated means that Havering Council now has legal obligations to clean the site up which it has not had previously.
Soil analysis conducted in November 2023 showed that the land could contain asbestos, as well as plastic bags, polystyrene and asphalt.
It has previously been used as a cannabis farm and for weapons storage.
Council leader Ray Morgon said: "For too long, residents have suffered the consequences of fires from Launders Lane.
"By formally identifying the site as contaminated land, we are sending a clear message: we will not stand by while our residents' health and quality of life are put at risk."
He added that it was a “turning point” for people who live close to the dump.
