A few of the reports that have been investigated by GEPAN/SEPRA show ground traces that may be associated with the events reported by witnesses. Similar cases have been documented by other investigators. Phillips (1975) prepared a catalog of 561 such cases as a CUFOS report.

GEPAN/SEPRA has investigated only cases for which the following conditions are met:

1. Information concerning the event has come to GEPAN/SEPRA from an official source such as the Gendarmerie, local police, etc.
2. The event is recent (a few hours to a few days old).
3. The area has been protected and the traces have been preserved.
4. Sampling and measurements have taken place within a short time after the event.
5. Meteorological conditions have been favorable for preservation of the traces (no rain, etc.).

It is also desirable, but not essential that the event has independent credible multiple witnesses.

The first steps — to protect the site, to make measurements, and to begin collecting samples — are usually carried out by the Gendarmerie who have a complete set of instructions in a manual prepared by GEPAN/SEPRA, who have also devised procedures to be implemented by specialized laboratories for the collection and analysis of samples. When the services of a specialized laboratory are requested, the laboratory personnel will go to the site for in situ sampling.

Soil has the capability of retaining the effects of several processes including mechanical, thermal, magnetic, radioactive, and physicochemical processes.

Mechanical: A continuous or brief mechanical pressure causes a distortion of the soil. The compression of the soil can be measured by a penetration instrument, for instance.

Thermal: Measurement of the quantity of water in the soil, as compared to nearby control samples, allows determination of the amount of energy required to reduce the water content to that level.

Magnetic: Some soils have a high magnetic remanence. In this case, it is useful to examine the magnetic pattern of the soil with the help of magnetometers either in situ or (after sampling) in a laboratory.

Radioactivity: Such measurements may be made in situ or carried out on samples in the laboratory.

Physicochemical: Samples from the trace region and control samples away from the trace region can be analyzed for molecular, atomic and isotopic composition, etc.

Velasco described in detail their investigation of an event that occurred near Trans-en-Provence, France, on January 8, 1981 at about 5:00 p.m. (Bounias, 1990; Vallee, 1990; Velasco, 1990; see Section 15.) One weakness of this case is that there was only one witness. The witness was working in his garden when he heard a low whistling sound. Upon turning around, he saw an ovoid object in the sky that approached the terrace at the bottom of the garden and landed. The witness moved forward cautiously to observe the strange phenomenon but, within a minute, the object rose and moved away in the same direction from which it had arrived. It continued to emit a low whistle. The witness approached the scene of the apparent landing and observed circular depressions, separated by a crown, on the ground.

The Draguignan Gendarmerie arrived the next day (January 9) to investigate the report and, following GEPAN/SEPRA instructions, took samples from the ground and from the vegetation. The Gendarmerie found two concentric circles, one 2.2 meters in diameter the second 2.4 meters in diameter. Between the two circles was a raised area 10 cm wide. They found, on this raised area, two sectors, diametrically opposite, each about 80 cm long, that contained black striations similar to abrasion traces.

A team from GEPAN/SEPRA carried out a site visit on February 17, 1981, 40 days after the event. The trace was still visible since there had been very little rainfall since January 8. The arc-shaped area, lighter than the rest of the terrain, was still visible. The soil in this region was heavily compacted, forming a crust. Soil samples were taken both on January 9 and on February 17. These samples were then forwarded to various laboratories equipped for physical and chemical analyses. It was found that the compacted soil had a thickness of 6-7 mm. There was no trace of organic compounds such as one might expect to be produced by combustion. There was some evidence of iron in the form of striations about 1 micron thick, but the iron was not accompanied by chromium, manganese or nickel as would be the case for steel. There was some evidence of polymers. Traces of phosphate and zinc were also found. Traces visible as striations seemed to have been produced by a combination of mechanical and thermal effects.

Visual and microscopic examination revealed that, apart from the striations, the soil had been compacted without major heating, since the structure of calcium carbonate was not affected. Velasco has made an order-of-magnitude estimate indicating that, to produce the measured compression of the soil, one would need a stationary object of about 700 kilograms. On the other hand, the same indentations in the soil could have been made by an object of lower mass if the object were moving at a few meters per second at the time of impact.

The panel was intrigued to learn that ground traces appear to be associated with some UFO reports. These traces could of course be spurious with no relation whatever to the reported event, they could be due to hoaxes, or they could in fact be related to a real event. Clearly, it is essential to devise measurement procedures that can distinguish between these three possibilities. For this to be possible, it would definitely be helpful to have "baseline" measurements for some likely spurious causes and for hoaxes. The possible spurious causes would of course depend upon the location in which the event occurs. For instance, in the Trans-en-Provence case in which the event occurred in a vegetable garden, the trace may have been caused by some piece of gardening equipment such as a metal water barrel. Similarly, someone perpetrating a hoax might have used a standard or manufactured wheeled object. Rather than leave the effects of such spurious causes or hoaxes up to speculation, it would clearly be advantageous to have firm information on which to base a judgment such as could be provided by relevant experiments. The investigators could move a water container to a similar patch of earth, or create a trace with a wheeled heavily laden object, and then compare measurements of those traces with measurements of the trace associated with the UFO report.

Experiments such as the above could be specific to a particular case or they could be generic. If such experiments became the rule rather than the exception, it would become possible for an investigator to consult a catalog of spurious causes or of hoaxes as well as a catalog of claimed "real" events.

In some cases that involve an apparent disturbance to the soil, there may also be an apparent injury to vegetation. Velasco stated that four such cases have been investigated by GEPAN/SEPRA: the "Christelle" case of November 27, 1979; the "Trans-en-Provence" case of January 8, 1981; the "Amarante" case of October 21, 1982; and the "Joe le Taxi" case of September 7, 1987.

In the Christelle case, in which grass was flattened in a uniform direction, plant physiology analysis was subsequently carried out by Professor Touze of the Laboratoire de Physiologie Végétale de l'Université Paul Sabatier (the Center for Plant Physiology, Paul Sabatier University), Toulouse. The Trans-en-Provence case will be discussed later in this section. In the Amarante case, that took place near Nancy, grass was lifted up, the amarante leaves withered, and the amarante fruit seemed to have exploded. The plant physiology was examined by Professor Abravanel , also of the Laboratoire de Physiologie Végétale de l'Université Paul Sabatier (the Center for Plant Physiology, Paul Sabatier University), Toulouse. In the Joe le Taxi case, birch leaves were affected by the incident, and a biochemical analysis was carried out by Professor Michel C. L. Bounias of the Biochemistry Laboratory at INRA (National Institute of Agronomy Research), University of Avignon.

In the Trans-en-Provence case of January 8, 1981, discussed also in the previous section (Bounias, 1990; Vallee, 1990; Velasco, 1990; see Section 15), the Gendarmerie took one sample 1.5 meters from the center of a ground trace on January 9 and another sample, 20 meters from the center, on January 23. On February 17, 1981, investigators from GEPAN/SEPRA visited the site and took a series of samples beginning at the center of the ground trace and ending 10 meters from the center. Bounias examined the samples in his laboratory. The principal procedure for biochemical analysis was that of determining the chromatograms of the pigments. This yielded information for a number of biochemical components (chlorophylides; xanthines; oxychlorophylls; lutein; chlorophyll A; chlorophyll B; pheophytins; and ß carotene).

In samples taken from the periphery of the ground trace, the chlorophyll A content had been reduced by 33%, the chlorophyll B content by 28% and the pheophytin content by 31%. Bounias also found that the ß carotene content had been reduced by 50-57% and the violaxanthine content by 80%. The above changes, which normally occur as the result of aging of a plant, were found both in the samples removed by the Gendarmerie within one day of the event, and by the samples taken by the GEPAN/SEPRA investigators 40 days after the event. As one may see from the article by Bounias (1990), the biochemical changes show a strong correlation with distance from the center of the event. It appears that the magnitude of the effect is associated with a specific quantity (the difference in free enthalpy) associated with the biochemical change. According to Bounias, the glucide and amino-acid content of very young leaves had been changed to become nearer the content characteristic of old leaves.

Bounias carried out certain experiments to try to determine what form of trauma may have been responsible for these biochemical changes. As a toxicologist, Bounias rejected the hypothesis that the changes could have been caused by a deliberate act involving chemical poisons. Bounias also found that some of the changes could have been caused by powerful microwave radiation. However, microwave radiation by itself would not explain the photosynthetic breakdown or certain other characteristics of the injuries. Bounias found no evidence of effects that one might expect to be produced by ionizing radiation. This is consistent with the fact that there was no trace of radioactivity at the site.

Velasco also reported the GEPAN/SEPRA investigation into the "Amarante" case that occurred at Nancy on October 21, 1982. The witness, who is a biologist, reported that an ovoid object descended into his garden but did not descend lower than 1 meter above the ground. The witness observed the object for 20 minutes before it took off vertically into the sky. The witness did not hear any sound or feel any heat during the encounter, nor were there traces on the ground. However the witness reported that, just before the object departed, the grass blades stood up straight. Subsequent investigations showed that this phenomenon could be reproduced in the laboratory by using very intense electric fields (several tens of kV/m).

The GEPAN/SEPRA investigators found that the amarante plants located near the object had become desiccated whereas similar plants further away were in normal condition. The fruit of plants from the vicinity of the object looked as if they had been cooked. Further biochemical analyses of the samples gave results consistent with what one would expect of plants that had been dehydrated.

The panel was impressed by the detailed information that can be obtained by laboratory investigation of samples of vegetation taken from the location of a claimed UFO incident. It appears that a great deal more could be done in the way of laboratory experiments to study the effects of various kinds of radiation and other forms of trauma upon vegetation. One should also examine the kinds of effects that could be produced by techniques that might be involved in a hoax, such as chemicals, heat from a blow torch, etc. Such studies would help identify a hoax, if it has been perpetrated, or the studies may lead to the conclusion that a hoax is a very unlikely explanation of the traces. In the latter case, it may or may not be possible to identify the type of technological device that would produce the radiation, or combination of radiations, necessary to produce the identified injuries to the vegetation.

UFO reports sometimes include references to physiological effects on witnesses. These effects can range from mild temporary sensations to long-term injuries. Such cases were reviewed by Schuessler. (See Schuessler, 1996, and Section 15).

Among the temporary sensations experienced by witnesses, Schuessler gave the following examples: a strong sensation of heat that was reported in association with an event at Mount Rouge, Quebec, Canada on September 20, 1972; a "cold" feeling reported by a witness to an event near Eggardon Hill, England, on September 24, 1974; an experience of shock, reported by two witnesses to an event near Tyler, Texas, on November 26, 1976; a sensation like being "hit with a wet blanket" and a very uncomfortable feeling of being unable to move, reported by two witnesses of an event that occurred near Anderson, Indiana, on August 12, 1981; and a tingling sensation, an inability to move, and an experience of having the hair on the neck stand on end, that were all reported by a witness of an event that occurred near Barnsley, Yorkshire, England, on August 15, 1986.

Schuessler also described several cases in which witnesses experienced multiple sensations including the following: uncontrollable hand motion; eye irritation; difficulty in breathing; an acid taste in the mouth; a sensation of the hair on the arm standing up; loss of consciousness; eye damage so that the witness could barely see; a mark on the hand of a witness where she reported that she has been hit by a beam; a red crust of soft skin on the face that felt sensitive to the touch; and a sensation of heat. Physiological effects were reported that could be long lasting, including the following: burns; temporary deafness; singeing of hair; laceration; swelling; nausea, that could continue for months and could lead to weight loss; loss of sight that could take months to overcome; severe itching; memory loss; burn marks; double vision; nose bleeds; and change of urine color. For more information on cases leading to such effects, see Schuessler (1996).

Schuessler gave an extensive account of a notable case that occurred near Dayton, Texas, on December 29, 1980 (Schuessler, 1981; 1988; 1998). This is known as the "Cash-Landrum" case since it involved Betty Cash, then a 51 year old business woman, and Vickie Landrum, then a 57 year old employee in a restaurant. It also involved Landrum's grandson Colby, then 7 years old. According to their reports, they encountered a large diamond-shaped object hovering above the road in front of them. Flames were belching from the bottom of the craft. The interior of the car became hot, forcing them to leave the vehicle. However, Colby and Landrum returned to the vehicle out of fear. Cash remained outside the automobile for seven to ten minutes. The object rose into the night sky and moved away. According to their reports, the object was accompanied by 23 helicopters that Cash and Landrum assumed to be military.

The witnesses were initially affected mainly by the heat and the bright light, and they developed headaches. During the night, Colby vomited repeatedly and his skin turned red. The same happened to Landrum. Cash fared even worse: large water blisters formed on her face and head, and by morning her eyes had swollen shut. The three witnesses continued to have severe nausea: even water would make them vomit; they developed diarrhea, and their health deteriorated severely. Cash was taken to a hospital where she was treated as a burn patient. This was the first of more than two dozen periods of hospital confinement for Cash.

Schuessler listed the following medical problems developed by the three witnesses: eyes swollen, painful and watery; permanent damage to the eyes; stomach pains, vomiting and diarrhea; sores and scarring of skin, with loss of pigmentation; excessive hair loss over a several-week period, the new hair having a different texture from the old; loss of appetite, energy and weight; damage to fingernails and shedding of fingernails; increased susceptibility to disease; and cancer.

The Cash-Landrum case seems to be unique in that there is detailed documentation of the injuries (photographs, etc.), and of the subsequent medical treatment. The case seems also to be unique in that it appeared to involve military helicopters, raising the possibility that a secret military operation was in progress (Schuessler, 1996).

As Schuessler pointed out, most witnesses who suffer from injuries do not tell their physicians about the events that appear to have led to injuries and, if they do, they find that the physician does not believe them. Follow-up examinations are rare, and investigators usually collect little more than anecdotal data. Nevertheless, some patterns seem to emerge concerning the types of injury that are reported: it appears that burns (and/or sensation of heat) and eye problems are the most frequently reported forms of injury.

The panel members were concerned with these accounts, since it appears that some events related to UFO reports may constitute a public health problem. However, the evidence is weakened by the fact that, in most cases, no unaffected and independent witness is present. The available evidence (that is admittedly sparse) seems to be indicative of microwave, infrared, visible, and ultraviolet radiation, although a few cases seem to point towards high doses of ionizing radiation such as X-rays or gamma rays. Most of the reported eye problems (sometimes long lasting) may be attributed to strong UV radiation. Superficial burns may be due to UV radiation, but deeper burns may be due to microwaves. It may be noted that injuries to vegetation (see Section 11), that include desiccation and "aging," also may be due in part to microwave radiation.

Unfortunately, cases that involve injuries to animals and people are usually not well documented, and lack an adequate description of the injuries and of the follow-up investigations (if any). Research is also made difficult by the fact already mentioned that victims typically give no information to the attending physician and that, when they do, the physicians tend not to believe them. This does not help in the medical diagnosis and treatment. Some cases come to the attention of UFO investigators only years after the event. Nevertheless, it appears that the reported cases involve very uncommon injuries, that have probably been brought about by sources of intense radiation that are usually not accessible to the public.

Schuessler's presentation included an account of the protocols developed by UFO medical experts for the investigation of such cases. The panel suggested that additional relevant tests include tests for radioactive contamination or intake, and also tests for possible chromosomal changes in the lymphocytes that might yield evidence of exposures to ionizing radiation. Investigators and physicians could employ some of the general procedures developed and published by the International Commission on Radiological Protection (ICRP), for responding to emergency and accidental exposures to ionizing radiations.

For the well-being of victims, and for research purposes, it is important that victims receive treatment rapidly. For this to occur, it is necessary that doctors should be educated to immediately report cases of unusual injuries, such as those mentioned in this section, to an official organization. For research purposes, it is essential that there be strong witness testimony supplementary to that of the victims of the event. Furthermore, it would be helpful if an investigation protocol could be developed for this important category of cases that would guide the investigators as well as the examining physicians.

Vallee reviewed several cases in which material samples were reported to be associated with unexplained aerial events. Vallee specified four criteria that led to his selection: the documentation of witness testimony; the circumstances surrounding the recovery of the specimen; evidence linking the specimen to the reported object; and laboratory analysis of the samples.

Vallee devoted most time to a case that occurred at Council Bluffs, Iowa, on December 17, 1977. Several residents of the town observed a bright flash at 7.45 p.m. The flash was followed by flames 8 to 10 feet high. When the witnesses reached the scene of the event, they found a large area of a dike at Big Lake Park, on the northern city limits, covered with a mass of molten metal that glowed red-orange and had ignited the grass.

Police and firefighters reached the scene within minutes of the event. One law-enforcement officer described the molten mass as boiling and running down the edges of the levee over an area of about 4 to 6 feet in extent. The central part of the material remained warm to the touch for another two hours. There were 11 witnesses in all. Two of the eleven witnesses had observed a lighted object in the sky prior to the fall of the material.

The sample recovered from the event was analyzed at Iowa State University and at the Griffin Pipe Products company. It was found that the metal was mainly iron with small amounts of alloying materials such as nickel and chromium. The analysts concluded that the material was similar to carbon steel. However, they eliminated the following four possibilities:

a) An unknown person poured molten metal on the ground as a hoax;

b) An unknown person created molten metal as a hoax by using thermite and ordinary metal;

c) The material came from equipment from an aircraft; or

d) The event was due to a meteoritic impact.

The origin of the sample therefore remains unidentified.

Vallee also discussed the following cases:

Maury Island, Washington, June 21, 1947. Debris that was claimed to be associated with an aerial explosion appeared to be similar to debris from a Tacoma slag mill, leading the authorities to conclude that the case was probably a hoax. However, some aspects of the case have never been fully elucidated.

Campinas, Brazil, December 14, 1954. An object, described as disk-like, was said to have wobbled and lost altitude and to have emitted a thin stream of silvery liquid that was subsequently determined to be tin.

Vaddo Island, Sweden, November 11, 1956. Witnesses found a shiny "rock," hot to the touch, near the landing site of a strange object. The "rock" was found to be composed of tungsten carbide and cobalt.

Vallee also gave brief mention of the following cases: Aurora, Texas, April 17, 1897; Washington, D. C., 1952; Ubatuba, Brazil, date on or before September 1957; Maumee, Ohio 1967; and an event that occurred in Bogota, Columbia either in 1975 or in 1976.

The panel found that reports of unusual metallic residue following the observation of an unexplained aerial phenomenon are detailed enough for comparative studies to be undertaken. The Council Bluffs case is notable since the conditions of witness availability and reliability, on-site testimony from law-enforcement officers, and rapid analysis, appear to have been satisfied. Some of the other cases, such as the Bogota case and the Ubatuba case, are sufficiently intriguing to encourage investigators to expand their field investigations.

The purpose of this section is to summarize ideas of what might be done to implement the panel's suggestions that were presented in their Summary Report (Section 1). The panel's observations and recommendations may perhaps be summarized very briefly as follows: The UFO problem is not simple and should receive more attention, with an emphasis on physical evidence; regular contact between UFO investigators and the scientific community would be helpful, as also would institutional support; and the possibility of health risks associated with UFO events should not be ignored.

The panel was greatly impressed by work reported from GEPAN/SEPRA, the French project originally GEPAN and now known as SEPRA (see Appendix 1), and there is no doubt that the best prospect for real advance in our understanding of the UFO problem would be the creation of similar projects in other countries, for the following reasons:

1. Such a project could be mandated to obtain access to relevant data such as police records, radar records, etc.
2. The project could organize and draw upon a network of laboratories and consultants.
3. The project could set up and maintain a central database.
4. The project could construct and operate one or more mobile "observatories" that would include a number of cameras and other detectors including, as a minimum, optical, infrared, spectroscopic, acoustic, magnetic and radiation instruments.
5. New cases could be investigated from the outset purely on the basis of data collected by official channels and procedures.
6. If there is indeed a health hazard associated with some events related to the UFO problem, some government office should offer a response to this hazard.

Even the most speculative hypotheses could be evaluated by a well conceived and well supported project. For instance, an analysis of the isotopic composition of material specimens could provide evidence that a specimen is probably of extraterrestrial origin, and analysis of the spectra of stationary objects, if it were to yield evidence of red-shifts or blue-shifts corresponding to a fraction of the speed of light, could indicate that some extraordinary physical process is involved. However, material specimens are rare, and it would take special equipment (that does not now exist) to obtain high-resolution spectra of transient and unpredictable sources.

We realize that not every country could duplicate GEPAN/SEPRA, since not every country has a national police force similar to the French gendarmerie. Furthermore, the creation of any such project would represent a political act that can be taken only by a national government for its own reasons or in response to public pressure.

For these reasons, it is necessary to be realistic and look for more modest approaches that could be initiated without government action. It would appear that progress is most likely to come about through incremental changes in institutional support and incremental changes in level of interest, these changes occurring symbiotically. We therefore inquire into what small positive changes could be made by scientists and by private institutions such as societies, journals, universities and foundations.

The most important change that could be made by scientists is to become curious. In view of the fact that modern UFO reports began in 1947, in view of the emergence of clear patterns in UFO reports (as was established some time ago by Poher [1973] among others), and in view of great public interest, it is remarkable that the scientific community has exhibited so little curiosity in the past.

There is no doubt that this lack of curiosity is due in part to a lack of reliable and accessible information. When Sturrock carried out a survey of members of the American Astronomical Society in 1975, he asked if members would like to obtain more information about the UFO problem, and most respondents replied that they would (Sturrock, 1994; 1994b; 1994c). Sturrock also asked whether members would like to acquire this information from lectures, symposia, books, or journal articles; most respondents wanted only journal articles. At that time, most editors of most scientific journals would not consider accepting an article on the UFO problem. Since that time, the Society for Scientific Exploration has been founded, and its journal is now in its 12th year of publication. However, the journal can be found in only a few university libraries. Hence the situation persists that it is not easy for scientists to obtain information about the UFO problem by the normal process of going to the library and looking up journal articles.

Clearly, there is a need for a change in policy on the part of journal editors. The scientific community would become much better informed if the major multi-disciplinary scientific journals were to carry occasional review articles that could guide readers to the specialized journals where more detailed information could be found.

Similarly, it would be very helpful if the major scientific societies were occasionally to include a review lecture or a review session containing several lectures devoted to the UFO problem. Specialized societies could also play an important role. For instance, a meteorological society could review those meteorological phenomena that are most likely to be responsible for UFO reports.

It is likely that more scientists at universities would take an interest in this problem if they felt that their activities would receive the same recognition and level of support as their more conventional research. Moreover, students would become better informed if there were occasional lectures or seminars on this subject. Investigators could help this process by developing resource material for such seminars.

However, even without waiting for such a change in policy of journals, societies and universities, scientists could exhibit a great deal more curiosity than they do now. Of course, it must be professional curiosity if it is to lead to professional results. It is not enough for a scientist to occasionally pick up a tabloid at the supermarket check-out stand. To become at all knowledgeable about the subject, a scientist should read the Condon Report (Condon & Gillmor, 1969), the report of the UFO Subcommittee of the American Institute of Aeronautics and Astronautics (Kuettner et al., 1970) and its supporting articles (MacDonald, 1971; Thayer, 1971), and obtain as much information as possible about government-sponsored studies such as U. S. Air Force projects Sign, Grudge and Blue Book. [See, in particular, Blue Book Special Report No. 14 (ATIC 1955).] Jacobs (1975) remains an excellent introduction to the history of this topic. He or she would then be well advised to read some of the reports of GEPAN/SEPRA, the French official study group. (See Appendix 1.)

Study of the material mentioned in the preceding paragraph may arouse sufficient interest that a scientist would wish to become involved in actual research. Unfortunately, it would be far more difficult for a scientist to plan effective research on the UFO problem than in his or her main research area. The scientist would therefore be well advised to collaborate with one or more investigators with experience in field work or some other aspect of UFO research. Such collaboration would be greatly facilitated if, as the panel recommended, there were "some form of formal regular contact between the UFO community and physical scientists." Such contact could help acquaint a broader spectrum of UFO investigators with the normal procedures, protocols and standards of scientific research.

The proposed further contact could take the form of workshops similar to that held at Pocantico: such workshops could focus on some more limited aspect of physical evidence, or they could deal with quite different aspects of UFO research. The panel recognized the importance of "strong witness testimony," but of course physical scientists have no expertise relevant to that aspect of the problem; it might therefore be very helpful to hold a workshop dedicated to the collection and evaluation of witness testimony.

In the absence of government funding for UFO research, foundations and corporations can play an important role. It is likely that significant progress would be made if funds were to be made available for the support of (a) further workshops similar to the Pocantico workshop, (b) a few research projects that might be identified during the workshops, and (c) one or more symposia at which the results of these research projects would be presented and discussed.