Chapter 2– Activities of the Scientific Committee in the Context of International Research
p. 73-71
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2.1 Historic reference points and antecedents
1Since its discovery on September 12, 1940, Lascaux Cave has had the profound honor of being considered as a benchmark in the history of humanity. For this reason, it was designated in 1979, along with other decorated caves of the Vezere Valley, as a World Heritage Site. It is also for this reason that those who are responsible for its conservation are subject to the closest scrutiny and, at times, the severest criticism.
2We can thus understand why as early as 1947 it was considered necessary to appoint the first of the scientific commissions entrusted with the responsibility of contributing to its preservation: the Commission in charge of monitoring the atmosphere of the cave, which was partly composed of medical doctors. The mission of this commission was to ensure the preservation of the prehistoric paintings. This signifies that seven years after its discovery, the cave was already starting to give cause for concern. Two years later, in 1949, this commission was succeeded by a Stone Commission, which addressed the threats to the preservation of the cave’s parietal works and the discomfort experienced by visitors due to excess levels of carbon dioxide. Created in March 1963, the Commission for the Scientific Study and Preservation of Lascaux Cave is the most famous. It was this commission that persuaded André Malraux, Minister of Cultural Affairs, to close the cave to the public, a decision made on April 20, 1963. This commission operated until 1976. In 1993, a regional commission for the scheduling of studies and activities relative to the protection of Lascaux Cave was created with the collaboration of the Aquitaine Regional Director of Cultural Affairs. This committee operated until 1996, after having submitted its conclusions in November 1995 in the form of a report entitled Lascaux: État des Lieux. Based on its proposals, the activities realized in 2000 were initiated.
2.2 Missions, principles and functioning
3The current Lascaux Cave Scientific Committee, composed of twenty-five members, began its work on September 24, 2002. Its missions were defined by a ministerial order on August 22, 2002 and renewed on June 15, 2006. They were three in number:
– to realize a complete diagnosis of the sanitary condition of the cave;
– to propose solutions to the problems observed;
– to ensure that a satisfactory sanitary condition is maintained over the long term; in other words to address both the immediate and long-term needs; all the activities conducted by the committee since 2002 have adhered to this twofold obligation, while confronting two microbiological crises, in 2001 and in 2007, manifest by the resurgence of “black spots”.
4The work of the committee has adhered to the following basic principles.
5Humility. In the face of the problems to be solved in the short term and the long-term solutions to be developed, no domain of research should be excluded and no scientific cooperation should be neglected.
6Multidisciplinarity. It was indeed evident, since the first conservation measures were applied to Lascaux in the 1940’s, that it would be necessary to combine archeological competencies with geological, climatological and microbiological ones, to cite only the principal domains.
7International collaboration. The experience acquired by the Laboratoire de Recherche des Monuments Historiques (LRMH) and the Centre National de Préhistoire has shown that all countries with a prehistoric cave art heritage are now confronted with preservation difficulties and with the threat of the destruction of this underground heritage. It was therefore decided to integrate different analyses of such difficulties and the various solutions that had already been implemented. From the moment of its creation, the committee therefore called upon international competencies. This is still the case in 2009: Germany, Spain, Italy and France are working together in this committee. UNESCO and the Council of Europe are following these activities attentively. The scientific community present at this symposium is one more indication of the international dimension of this project.
8For the past seven years the committee has made every effort to never lose sight of these three principles.
9I can now describe the nature of this committee and its manner of operation. It is both a scientific council and a steering committee bringing together experts from the various disciplines concerned (geologists, geomorphologists, karstologists, hydrogeologists, microbiologists, climatologists, specialists in preventive conservation and a few archeologists) working in symbiosis with heritage curators and managers from the Ministry of Culture. This hybrid formula may be open to criticism, but it nevertheless has the considerable advantage of shortening the decision-making process since the representatives of the State–the client with regards to the operations proposed by the committee–are present during discussions and can immediately express their opinion with respect to these proposals.
10Since its creation, the committee has held 57 meetings, including 19 plenary meetings and 38 for its permanent delegation. These 57 meetings have all been recorded in minutes filed with the DRAC of Aquitaine (Regional Department of Cultural Affairs) where they can be consulted. Experts from outside the committee have been invited to take part in its operation or have been consulted depending on their specialties.
11Since 2003, the action of the scientific committee has been completed by the creation of a sanitary monitoring commission at the level of the Department of Dordogne and placed under the authority of the Prefect. This commission brings together State services, local authorities and the Chairman of the Scientific Committee. It is responsible for examining all development or construction projects envisaged in the vicinity of the cave that could modify or be harmful to its environment. It is in the framework of this committee that the project for the comprehensive protection of the hill on which Lascaux is located has been conceived.
2.3 The situation in 2002
12When the scientific committee met for the first time, on September 24, 2002, it encountered a disturbing situation at Lascaux. The cave was just emerging from the serious microbiological disorders that had jeopardized its prehistoric art works in 2001. Though the major crisis was over, following the treatments prescribed by the LRMH, the cave was far from having returned to the state of sanitary equilibrium of the previous decades; it still required attentive and regular care and at best could be considered to be in a state of convalescence.
13Two documents made it possible to analyze the situation:
– a report dating to November 1995 realized under the direction of Jean-Michel Geneste, entitled Lascaux: État des Lieux, reviewed the situation concerning the preservation conditions of the paintings and recommended a series of urgent measures to be realized in order to maintain the cave in good sanitary condition;
– a summary note drawn up by Isabelle Pallot-Frossard, Director of the LRMH, following the contamination in 2001, insisted on the need to realize an exhaustive condition report on the prehistoric paintings and a detailed assessment of the cave’s climate regulation system.
14These documents, completed by a visit to the cave by the committee members, served as the starting point for the reflections that have since made it possible to draw up a global project.
2.4 A global project to maintain the sanitary equilibrium of Lascaux Cave
15In June 2003, nine months after its creation, the committee decided to prepare a global research and intervention project. This project was adopted in May 2004 and was immediately put into application. To achieve this, it benefited from the appointment of a project leader, Marie-Anne Sire, responsible for coordinating all of the activities. Ms. Sire was replaced in 2008 by Muriel Mauriac. The project integrated all of the actions already taken since 2002. It had two main objectives: to treat the symptoms of the diseases (white mold in 2001, black spots in 2007); and to identify the causes of these diseases. In other words, it would address both short and long term issues. This program is composed of four sections:
– controlling the development of the microorganisms that appeared in 2001;
– obtaining a better knowledge of the cave and its environment;
– ensuring the long term preservation of the site;
– creating an instrument for calculation, knowledge acquisition and aid in decision making: the Lascaux simulator.
2.4.1 Controlling the development of the microorganisms that appeared in 2001
16This was evidently the priority. The scientific committee conducted this work with two objectives.
17The development of chemical treatments that would allow rapid actions to be taken in the case of a fungal and bacterial invasion. The goal here is to eradicate or, more precisely, to render inactive the main agents of the aggression: fungi (Fusarium solani, Ulocladium, Scolecobasidium, etc.) and bacteria living in symbiosis with these fungi, particularly Pseudomonas fluorescens. After excluding various treatment hypotheses with risky consequences (treatment by gassing, biological control, etc.), the committee favored the immediate continuation of fungicidal treatments, which would be gradually replaced by the manual removal of the molds, followed by the use of a device specifically developed for these purposes: an injector-extractor. At the same time, the search for other treatment methods was encouraged.
18The realization of diverse analyses, which would be forcibly slow in their progression, destined to precisely determine the biological landscape of the cave: fungi, bacteria, cave-dwelling insects, etc. This interdisciplinary research would rely on two coordinated disciplines, microbiology and microclimatology, in order to understand the degree of dependency between the climatic parameters of the cave (air and stone temperature, relative humidity of the air), the hydric behavior of the stone and clays and the development of microorganisms.
2.4.2 Obtaining a better knowledge of the cave and its environment
19The activities in this domain were launched in four directions.
20Creation of a documentary reference base. Numerous studies have been carried out at Lascaux since its discovery. The best known ones concern its art works and the proposed interpretations of them, but dozens of articles and technical reports have also marked its recent history. From the time of its first meeting, the committee has desired to create a database bringing together all the archives and publications devoted to the cave in order to make the best possible use of them. It rapidly became evident that the history of the persons and organizations involved had resulted in a significant dispersion of the documentation over the years. The mission launched in April 2003 allowed the identification of 215 persons or organizations who had a part of these archives in their possession. Most of the archives have since been grouped together or analyzed and the database is now operational.
21Realization of a 3D survey. No additional works of any great magnitude have been carried out since the drawings and sections made by the engineer Claude Bassier in 1963. In order to create a digital simulation of the hygrothermal behavior of the cave, it was essential to have a 3D survey accompanied by a complete photographic coverage of the floors, ceilings and walls. Undertaken at the end of 2003, this survey has been usable since February 2006. It was completed in 2008 by a survey of the double-door airlock entrance and the machine room.
22Realization of a condition report. Since the crisis in 2001, the permanent monitoring system installed in every part of the cave has rapidly shown the limits of human observation and memory. The role played by subjectivity and emotion is too great. In order to precisely measure the progression or regression of the fungi and bacteria, and to compensate for these drawbacks, a full condition report of the conditions of the cave, as had been requested for some time by the LRMH, had to be undertaken. Starting in January 2004, the entire cave has been subject to a meticulous diagnosis concerning both the decorated and undecorated parts. The operation in the field–very slow due to the limited permissible number of hours of human presence in the cave each week–was completed in April 2007.
23Improving our knowledge of the geology and hydrogeology of Lascaux hill. Though a good knowledge of the karstic massif in which Lascaux is located had already been acquired before 2002, the scientific committee deemed it necessary to obtain an even better knowledge and understanding of this stone massif and its relationships with the cave and its environment. In particular, a clear understanding of the circulation of air and water in this massif allows us to more clearly delimit the catchment area from which polluted waters can reach the cave. This work began in 2005, and will soon be finished. It has already made it possible to adopt a policy allowing the State to extend its ownership of the surrounding land in order to control the entire catchment area.
2.4.3 Insuring long-term preventive conservation of the cave
24Four methods are applied to achieving this goal.
25Improving the technical installations. As early as December 2002, the scientific committee requested an expert assessment of the climatic assistance equipment installed in 2000. In June 2004, the conclusions of the expert assessment led to a revision of the use procedures of this equipment and then to the future designing of new equipment, once the Lascaux Simulator had become operational and its first results known, concerning in particular the near total disappearance of the convection phenomenon in the cave. In addition, a restoration or replacement of all of the technical installations was gradually implemented. This concerns the measurement instruments, electrical devices and the peripheral equipment of the climatic assistance system.
26Perfecting regulation of the immediate environment. It has been decided to undertake an analysis of climate changes since 1940, as well as of the vegetal cover and the modifications it has undergone. The results of this analysis will allow us to evaluate the significance of the climatic variations that have occurred over the last sixty years, and which have resulted in the near total disappearance of the convection phenomenon that contributed to maintaining the microclimatic equilibrium of the cave.
27Revising the procedures of access to the cave. A general review of the microbiological and microclimatic monitoring procedures will also be performed. Samples of the microorganisms will be taken and analyzed at regular intervals, without waiting for cave equilibrium disorders to appear. A weekly record of the condition of the cave and of human interventions was initiated in January 2003.
28Reinforcing the human resources for monitoring and regulating the conditions of the cave. To ensure that that all essential tasks are realized, an engineer, Stéphane Konik, has been assigned to Lascaux since 2007.
2.4.4 Creating an instrument for calculation, knowledge building and aid in decision making: the Lascaux simulator
29Both an instrument of knowledge and a decision-aid tool, the Lascaux digital simulator, launched in June 2005, was developed through collaboration between Bordeaux 1 University, the CNRS, the EDF Research and Development Department and the Ministry of Culture and Communication. Over several months, it has affirmed its role as an essential element for the long-term preventive preservation of the cave. It allows us to understand the climatic functioning of the cave and its natural and artificial evolution in relation to the changes, particularly morphological, that have occurred over time. It contributes to our interpretation of abnormal appearances of certain microorganisms and their development in liaison with the evolution of the physical milieu. It will also contribute to controlling the operation of the climatic assistance system whenever necessary.
2.5 Current activities
30I present here just a brief overview of current activities as a detailed presentation of them will be given in the following papers. The main activity consists of the continuation of the microbiology and microclimatology research program with a focus on the right part of the cavity where imbalances persist in the microflora. These two disciplines rely on the automated recording of data and on samples and analyses of microorganisms.
31The first phase of the design of the new climatic assistance system, launched in 2008, will be developed using the digital simulator. The calculations already made indicate that the creation of cold points, particularly in the right part of the cavity, could contribute to restoring the climatic stability and convection favorable to maintaining the sanitary equilibrium of the cave.
32Very strict monitoring of the “black spot” phenomenon continues in the right part of the cave and is recorded in weekly reports. A manual elimination of the fungi is carried out during certain verifications. At the same time, an impact study is being conducted on four very small test zones, varying the association of manual cleaning and biocide treatment. It has already been concluded that it is impossible to use manual cleaning, whatever the precautions taken, in the zones where there are engraved or painted works of art; this is prohibited by the extreme fragility of the cave’s stone support in this right part of the cave.
33Finally, equipment maintenance or replacement projects will be necessary outside of the archeological sectors (airlock entrance, machine room) and in the areas surrounding the cave since Lascaux requires permanent maintenance.
2.6 Conclusions
34To summarize, the committee and its scientific partners have developed their activities according to three time scales.
35In the short term, our goal is to eradicate the fungal contaminations to avoid any risk of them attacking the prehistoric paintings. This has been the main focus since 2000.
36In the medium term, our goal is to develop more efficient tools to anticipate the measures to be taken in the event of new invasions of fungi and bacteria. This has required us to obtain a better knowledge of the cave and its environment, to develop biocides better suited to the current climatic and biological situation and to create an entirely new digital calculation instrument: the Lascaux Simulator. Most of this work was achieved between 2003 and 2007.
37In the long term, it is necessary to take actions simultaneously inside and outside of the cave. Inside the cave, this consists of designing a new climatic assistance system capable of reducing the factors responsible for atmospheric and biological imbalances. This system should be operable in 2010. During this period, a study should be launched concerning the microbial ecology of the cave and the metabolic activity of the melanin-producing fungi at the origin of the “black spots”. Outside the cave, this work will first consist of creating a laboratory cave a few kilometres away in another Dordogne cave of no archeological interest, selected based on its similarities with Lascaux; this will be a materialization of the doctrine defined by André Malraux in 1963, stating that we must “Not to make a research laboratory of Lascaux”. The second phase of this project will be to transfer most of the tourist facilities that can disrupt the environment of the cave to the foot of the hill. At the same time, a new facsimile and public “interpretation center” will be installed in the valley. Named “Lascaux III”, this center is scheduled to open in 2014. Finally, we must salute here the determination of the Dordogne General Council, which has just decided to purchase the necessary land, and the district of Montignac, which has classified the entire Lascaux hill as a construction-free zone.
38All these measures finally contribute to realizing the dream of our predecessors since the 1940’s: to “sanctuarize” Lascaux hill. This symposium also provides us the opportunity to pay public tribute to the members of the scientific committee and to all those individuals who have never ceased to explore every possible manner to ensure the preservation of Lascaux Cave so that we may have the privilege of passing it down to the future generations.
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