Two and a Half Years Later, Basement Fire Finally Contained
- Following the devastating fires of summer 2022, subterranean lignite continued to burn beneath the forest floor in Hostens.
- despite the vast quantities of water poured by firefighters and three unusually wet winters, the underground fire persisted.
- The initial Landiras fire in the summer of 2022 ravaged over 20,000 hectares of vegetation, alongside another notable fire in La teste-de-Buch.
Hostens Forest Fire Finally Extinguished After Lingering Lignite Combustion
Table of Contents
- Hostens Forest Fire Finally Extinguished After Lingering Lignite Combustion
- Hostens Forest Fire: Persistent Lignite Combustion Finally Extinguished
- Frequently Asked Questions About the Hostens Forest Fire and Lignite Combustion
- Why did the Hostens forest fire persist for so long?
- What is lignite and why is it so combustible?
- What were the dangers of the ongoing lignite combustion?
- how was the lignite combustion in Hostens finally extinguished?
- What area was affected by the initial Landiras Fire?
- what are the plans for the Hostens natural area now that the fire is extinguished?
- What changes have been observed in the flora and fauna of the area?
- Summary of Key Data
- Frequently Asked Questions About the Hostens Forest Fire and Lignite Combustion
Following the devastating fires of summer 2022, subterranean lignite continued to burn beneath the forest floor in Hostens. Specialists had to extract the burning materials, spread them out, and douse them with water to lower their temperature.
despite the vast quantities of water poured by firefighters and three unusually wet winters, the underground fire persisted. though, on March 19, it was announced that the combustion had finally ceased after two and a half years.
The initial Landiras fire in the summer of 2022 ravaged over 20,000 hectares of vegetation, alongside another notable fire in La teste-de-Buch. Although the fire was officially extinguished on September 28, 2022, a portion of the subsoil continued to burn, posing risks to both people and the surroundings.
Temperatures Reached 600°C Below Ground
the culprit behind this persistent combustion was lignite, a sedimentary rock intermediate between peat and bituminous coal.this natural coal, a combustible material, had been mined in the area until about sixty years ago.
This type of combustion reignited the Landiras fire in August 2022, after an initial extinguishing a month prior.
Three hotspots remained active in Hostens. By the previous autumn, two had subsided naturally, having fatigued their fuel. Only the area known as Petit Bernadas continued to smolder.
Smoke emanated from the ground approximately every ten meters, with surface temperatures “between 150 and 200°C,” according to Sébastien Fourcade, head of the office for the progress and management of sensitive natural areas in Gironde. This suggested that deeper within the soil, temperatures could reach as high as 600°C.
Combustion Materials Extracted from the Soil
competent authorities, including the Bureau de recherches géologiques et minières (BRGM), initiated extensive studies to understand why the fire persisted for two and a half years and, more importantly, how to extinguish it. The situation was unprecedented.
The strategy involved a meticulous process: “First,on the hot zones,the materials in combustion or hot in depth were extracted – it was sometimes necessary to dig up to five meters – then spread on a waterproof platform made of clay,before being sprinkled with water by the teams of the Departmental Fire and Rescue Service (Sdis). The treated area was then covered with clay,” explained Sébastien Fourcade.
Moreover, lateral bands filled with clay were installed at the boundaries of the lignite zone to create “a supplementary protection barrier.”
This thorough plan proved triumphant, and the situation is now under control. However, specialists remain cautious and vigilant, continuing to monitor the area.
The ongoing combustion of lignite in the subsoil posed risks to humans, due to the collapse of ash pockets, and to the environment, with the potential for larger-scale fires in the forest. Management organizations were sometimes forced to cut back regrowing vegetation to mitigate this risk.
Nature Undergoing Regeneration
The end of this smoldering fire marks a new chapter for this natural area, now undergoing regeneration. The Domaine d’Hostens and the lagoons of Gât mort are officially recognized as a biological reserve.
“The majority of the 481 hectares of the reserve will be managed by humans to restore and protect the remarkable species that are sheltered there, and 48 hectares will be protected,” the department stated.
Biological inventories of the fauna and flora in the fire-affected areas have begun and will continue until 2027. “Some species have returned, others (like reptiles) have disappeared, and new species have been observed,” the department of Gironde added.
The objective now is to preserve biodiversity, adapt the area to climate change, and reduce risks from extreme events such as fires.