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With temporary and permanent lay-offs of government workers in much of the world, it should be clear to everyone that government workers often perform needed and critically important services – environmental protection, food inspection, police and fire services, air traffic control, just to name a very few. And these jobs provide employment. Somehow, however, it hasn’t sunk in that these important services are provided by taxes (except, of course, for the Koch brothers and perhaps other corporations, who would apparently like to abolish taxes because they pay for the EPA’s environmental monitoring, but that’s another story for another day).

Where France truly has been positively avant-garde is in its monitoring of its old underground quarries. Unsung, underground heroes have worked and monitored the Paris underground for centuries to keep Paris from imploding into a giant sinkhole.

Rather than employing people in mining and fracking and in otherwise causing more troubles to the earth and its inhabitants, we need to be willing to pay more workers in the geological sciences to monitor the earth and to work to prevent sinkholes and related problems. This is a good and important job. It is critical for everyone’s safety.

27 June 1987. Small sinkhole at Sacred Heart Basilica, Montmartre being investigated. They explain that the church itself is well-supported but the surrounding area is in danger of collapse.

From this, we can also extrapolate the even greater need and importance of having workers monitor nuclear wastes for perpetuity. Although there are no more active quarries under Paris, the monitoring work must continue. In much the same way, even when we stop using nuclear energy, we will still have the waste to deal with.

The Inspectors of Paris’ old quarries have done an excellent job in protecting the public. Thanks to them, the only major land collapses, which have occurred over the last 20 years in Paris, were associated with the construction of major underground infrastructure: of Eole (now RER E) in 1995 and of Meteor (now Metro Line 14) in 2003. These disasters appear to be the responsibility of both those who chose to build these underground tunnel-infrastructures, given the fragility of Paris’ underground, and those responsible for the construction. The Meteor case, which caused a giant sinkhole under a nursery school, thankfully on the weekend, was ruled a combination of geology and fault of those responsible for the construction, mostly BOUYGUES. (By the way we had a feeling it WAS Bouygues who was at least partially responsible and checked). Bouygues won the contract for construction of the UK’s new nuclear power plant at Hinkley. Does everyone feel good now about French nuclear “expertise” in the UK? Report on the Meteor collapse, in French (we may come back to this another day): http://www.ladocumentationfrancaise.fr/var/storage/rapports-publics/034000193/0000.pdf
Information on the RER line E association with 1995 land collapse on Rue Papillon http://fr.wikipedia.org/wiki/Ligne_E_du_RER_d’Île-de-France http://www.senat.fr/questions/base/1996/qSEQ960314529.html

Plan paris gerards1908 jms
Map of Paris’ underground mine exploitations, by Emile Gérards, published 1908.

Here is information on Paris’ unsung heroes from the IGC web site (our translation from the French):
Paris Office of IGC
The General Inspectorate of Quarries (L’Inspection générale des carrières-IGC) is responsible for managing the risks associated with former quarries and with the dissolution of gypsum in Paris and in the majority of communes (municipalities) of the surrounding areas[1]

A Brief History

Between 1774 and 1776, a series of serious cave-ins caused by cavities of old quarries occurred around Paris public streets. The most important of these cave-ins occurred on the 17th of December 1774, Rue d’Enfer [literally: Street of Hell]. Officials and Parisians became conscious of the risks associated with the presence of large cavities under the capital. In fact, since Antiquity, the underground of Paris was exploited to produce construction material.

In order to assure the security of the population, King Louis XVI created the Inspectorate General Service of Quarries by a decision of the Council of State, the 4th of April 1777. This new service was charged with the inventory and mapping of former quarries, of surveillance and consolidation of the cavities situated under public property.
Paris, IGC
Starting in 1881, building permits for the Department of the Seine gave the General Inspectorate of quarries the task of issuing an opinion on each application located in a quarry zone. In 1945, this provision was extended by order of the prefect, to the entire Département of the Seine. Since 1968, the General Inspectorate of Quarries is part of the City of Paris.

The Jurisdiction of the General Inspectorate of Quarries

The General Inspectorate of Quarries is a department of the City of Paris. By convention, its scope of intervention extends to the Departments of Hauts-de-Seine and of Val-de-Marne and to the majority of towns in Seine-Saint-Denis.

For problems associated with the underground in towns located in Seine-Saint-Denis having no agreement with the General Inspectorate of Quarries (Aulnay sous Bois, Bobigny, Coubron, Le Blanc Mesnil, Tremblay en France and Vaujours), you can contact your local Town Hall. The General Inspectorate of Quarries of Yvelines, of Val-d’Oise and of Essonne manages the risks associated with abandoned former quarries and underground cavities in these three Departments. There are no services specifically managing the risks associated with the underground in Seine et Marne. For problems associated with the underground, you can address yourself to the Town Hall or the Department of Public Works for the Department of Seine et Marne.

The Role of the General Inspectorate of Quarries

Through its various duties, the General Inspectorate of Quarries manages risks associated with former quarries and the dissolution of anteludian gypsum in Paris, in Hauts-de-Seine, Val-de-Marne and Seine-Saint-Denis.

Knowledge of the Underground and the Associated Risks

The General Inspectorate of Quarries updates the atlas of former quarries of Paris and of the surrounding areas, which includes 458 maps scaled 1/1000, geological maps of Paris and of the suburbs scaled 1/5000 and related databases related to the subsoil (surveys, incidents …).

Since 1980, the service monitors a network of 330 piezometers to measure the groundwater [underground water] level in the capital. The information collected serves notably to produce maps of water circulation during floods of the Seine [River].

Additionally, it conducts general studies of a geological, hydrogeological and geotechnical nature, alone or in partnership with research organizations.

Providing Information

The General Inspectorate of Quarries provides information to individuals, contractors, solicitors (lawyers, notaries), surveyors, and to companies specializing in the nature of the subsurface of land plots and in the associated risks. The service responds to requests for written information and receives the public without appointment, three mornings per week. However, it does not provide information by telephone. It also answers requests for information from concession holders. At the request of municipalities, an engineer can participate in an information meeting regarding the risk associated with underground cavities.

Inform yourself on the Condition of your Property Underground

[Paris region only:] Would you like to know if your the underground of your property has a risk associated with the presence of an underground quarry? You can now ask online at the General Inspectorate of Quarries which offers a service of information on the underground of Paris and the surrounding departments 92, 93 and 94 [1].

Risk Monitoring
Paris Underground Quarry Inspection IGC
The General Inspectorate of Quarries regularly inspects the galleries of quarries still accessible under public property (several hundred kilometers), analyzes incidents associated with underground cavities and leads, in Paris, ground reconnaissance surveys.

Risk Mitigation

In case of application for a building permit, the General Inspectorate of Quarries issues recommendations, or requirements, on work to be done to ensure the safety of persons and property. Under public property (roads, parks, gardens etc..), the service can assure technical assistance in the context of reconnaissance work or ground consolidation. In Paris, it ensures the safety of public property.

Assistance in Case of Incident
Paris small sinkhole IGC
In case of incidents or of problems associated with the underground, the General Inspectorate of Quarries can provide technical assistance.

French original, on which our translation is based, contact information and other interesting documents (in French, of course) located here: http://www.paris.fr/pratique/sous-sol/inspection-generale-des-carrieres/p8603

Meteor construction collapse investigation-report (2003) http://www.ladocumentationfrancaise.fr/var/storage/rapports-publics/034000193/0000.pdf
RER line E (Eol) associated with the 1995 land collapse on Rue Papillon http://fr.wikipedia.org/wiki/Ligne_E_du_RER_d’Île-de-France

[1] The original says Petite Couronne, i.e. the three Departments around the city of Paris: les Hauts-de-Seine, la Seine-Saint-Denis et le Val-de-Marne. Until the end of 1967, part of these formed, with Paris, the Department of the Seine. http://fr.wikipedia.org/wiki/Agglomération_parisienne