Officials in France have confirmed the discovery of an ordnance disposal site in the northern French region of Meuse, where massive numbers of shells left over after World War I were dismantled, contaminating the soil.

In July, local authorities banned farmers from selling produce grown in the area, which had been used as farmland for several decades. The areas affected by the ban are close to Verdun, the northeastern French city that gave its name to the famous World War I battle in which more than 300,000 German and French soldiers died.

Results of initial soil testing carried out by France's Geological and Mining Research Bureau show traces of metal and chemical compounds in the soil including arsenic, lead, and zinc. Traces of explosives and industrial chemicals used in the disposal of the shells were also found.

"At the end of the two world wars, any shells that weren't fired were handed over to 'recyclers' who dismantled them in a rudimentary fashion and kept the metal," a spokesman for French environmental group Robin des Bois (Robin Hood) said. In June 2014, Robin des Bois released a report on the environmental impact of unexploded bombs to coincide with the 70th anniversary of D-Day.

According to local daily L'Est Républicain, the restrictions affect nearly 250 acres of farmland that was used from 1919 to 1926 as a site to dispose of old ordnance. A company called Clere & Schwander reportedly disposed of up to 1.5 million chemical shells and 30,000 high-explosive shells by "burning them, blowing them up, dismantling them, and draining them."

To establish the levels of contamination in the soil, authorities submitted samples of locally grown wheat, barley, and sweetcorn for testing. They also tested the milk of cows grazing in the area. Results from the testing appeared to show that safety thresholds for substances that have them — such as lead — were not exceeded. However, other substances detected during testing — including certain metals and explosives — do not currently have regulatory thresholds.

As a precautionary measure, authorities have decided to carry out further testing to determine whether or not the levels of these compounds are harmful to humans; the second round of testing could take up to six months.

"In the 20s, the public authorities didn't have the same environmental and security concerns as they do today," said François Crochet, who teaches at the university of Lorraine-Metz and sits on the scientific council of the French Commission for the Centenary of the Great War.

Officials have banned farmers from selling their produce until "health guaranteed have been provided." According to L'Est Républicain, farmers have already lost $167,000 worth of milk because of the restrictions.

Farmers in the area have not yet received any form compensation, despite a promise from authorities that they would be reimbursed "for their losses." Farmers are due to meet with local officials "very soon," said a spokesman for the prefecture.

Officials have also confirmed that the Environment and Energy Management Agency — a department of the ministry of ecology — has earmarked a $233,000 fund to compensate farmers.

Local authorities revealed the discovery at a news conference Tuesday — the first time officials have spoken publicly about the restrictions introduced in July. A mayor whose town is located within the affected area and who wished to remain anonymous said he found out about the discovery last week in the media.

Many people are wondering how it was possible for the authorities to forget about a vast bomb disposal site. According to Cochet, "overlapping responsibilities" within public agencies often cause institutions to drop the ball. The spokesperson for the Robin des Bois collective blamed the "oversight" on "administrative failings," and said that the authorities had shirked their duty to track the sites.

"We believe that there are other, similar sites that have yet to be discovered in France, particularly in the Lorraine [region]," the spokesperson said.

Officials were first alerted to the presence of the Clere & Schwander site while researching another nearby shell disposal site that was discovered in 2000. Nicknamed "Gas Square," the 10,000-square-foot clearing was used after World War I to dispose of nearly 200,000 German chemical shells.

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