ANNALES 11/'97
DELO NAŠIH ZAVODOV IN D RU ŠTEV/ACTIVITIES BY OUR INSTITUTIONS AND ASSOCIATIONS, 279-284
Andrej Kranjc
7th SYMPOSIUM ON W ATER TRACING 
Portorož, May 26th - 31st, 1997
Many important meetings have been organised this 
year at Portorož, including the meeting of the Central 
European presidents. Among the professional meetings 
the 7th SWT was without doubt one of the most impor­
tant. Under the simple name of symposium it was in fact 
the world's congress of specialists, using tracing tech­
niques for water research. Already the fact that these 
symposia are held every fifth year confirms the impor­
tance of the event.
The five years which elapsed from the previous sym­
posium (at Karlsruhe in 1992) were needed for the 
preparation of this one. First, it is necessary to say that 
the SWT symposia are not simple meetings where the 
specialists gather and discuss some topics. For the SWT 
a group of specialists belonging to the ATH (Association 
of Tracer Hydrology) choose appropriate karst terrain 
where they are trying different, if possible new, tracing 
techniques and methods. The results of these field ex­
periments are the essential part of the symposium. Of 
course the report about the experiments has to be pub­
lished, too, prior to the symposium, and the publication 
distributed to the participants. In 1992 at Karlsruhe the 
Slovene researchers, members of the ATH, offered to 
prepare the next, 7th SW T and to use Trnovsko-Banjška 
Planota karst plateau as a test area. Trnovsko-Banjška 
Planota is very important for Slovenia when drinking 
water reserves are taken into account. An ATH team 
came to Slovenia to visit the terrain and to discuss it 
with Slovene'colleagues and according to the conclu­
sions the organisation of the 7th SW T was assigned to 
Slovenia.
Here a special project "Transport o f pollutants in 
karst: tracers and models" was launched, co-financed 
mainly by Ministries of Science & Technology and of 
Environment & Physical Planning. In the frame of the 
project over 50 researchers of different professions 
(hydrogeology, hydrology, geology, physics, chemistry, 
geography, meteorology, etc.) coming from 18 institutes 
(Austria, France, Germany, Switzerland and Slovenia) 
investigated the waters of Trnovsko-Banjška Planota and 
their underground connections.
In 1995 the project was concluded and 1996 was 
used for analysing and interpreting the results and for 
preparing the final report. This was published in a spe­
cial number of "Acta carsologica" (edited by Karst Re­
search Institute at Postojna), no. XXVI/1 under the title 
"Karst Hydrogeological Investigations in south-western 
Slovenia", on 400 pages. The first part of the report pre­
sented basic data about Trnovsko-Banjška Planota 
(physical geography, hydrology, meteorology, geomor­
phology, speleology, geology, hydrology, water quality,
karst springs' fauna, vegetation). These data were not 
just gathered but for some of them special research was 
needed (detailed geological mapping of the Vipava and 
Hubelj springs, precipitation, évapotranspiration). The 
essential part of the publication contains the results of 
the project investigations: water balance and hydro- 
geological and hydrochemical investigations. Special 
attention was focused on the so-called "short events" 
(water pulses after heavy rain or snow melt) which is a 
new approach and very important in studying the proc­
esses. Taking into account that isotopes are a sort of 
"natural tracer", a very appropriate one, these investiga­
tions played an important role in the project. The gist of 
the publication are the results of water tracing in the re­
charge area of important springs (Vipava, Hubelj, Lijak, 
Mrzlek). All the tracing experiments were combined, i.e. 
different tracers were injected simultaneously into the 
swallow-holes, sinkholes, and shafts on the Trnovsko- 
Banjška Planota. Besides the answers to scientific and 
methodological questions, the results are very important 
regarding underground water connections in the frame 
of the Trnovsko-Banjška Planota aquifer. The knowledge 
of the connections is essential for the protection of the 
aquifer.
The results of the project can be very useful for water 
managers and for water users, that means for all the in­
habitants of the Trnovsko-Banjška Planota surroundings 
(Vipava valley, Nova Gorica and Idrija regions), as well 
as for the karst water specialists, who are using (or have 
to use) tracing techniques. At the same time the project 
and its publishing is a promotion of the Slovene research 
and science.
Publishing of the "Karst Hydrogeological Investiga­
tions in south-western Slovenia" was only one of the 
tasks the organiser, the Karst Research Institute, had to 
fulfill. Before the beginning of the symposium the pro­
ceedings had to be published, too. To enable the par­
ticipants of the excursions to follow the routes more 
easily, a small (100 pages) "Field Guide o f Karst in 
Slovenia" was prepared also. The symposium's proceed­
ings "Tracer Hydrology 97" which contain 63 papers 
(grouped in 5 chapters) on 450 pages, were published 
by Balkema, Rotterdam.
When all this work was done (we found out that five 
years is not such a long time), the symposium could 
start. In the Convention Centre of the hotel Emona at 
Bernardin (Portorož) over 160 registered members gath­
ered from 17 countries. Together with the occasional 
(non-registered) visitors, there were over 180 partici­
pants. Most of them came from all over Slovenia, from 
Germany and Austria. The rest were from European 
countries, from Malta to Ireland, from Spain to Slovakia. 
Specialists from other continents were present, too, from 
Brazil to China. It is necessary to mention that much 
more interest in attending the symposium was shown 
specially from the countries with economic problems
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ANNALES 11/'97
DELO NAŠIH ZAVODOV IN D RU ŠTEV/ACTIVITIES BY OUR INSTITUTIONS AND ASSOCIATIONS, 279-284
(India, Russia, Ukraine), but the organiser could not help 
them by other support than to exempt them the organi­
sation fees. In the future such meetings should be organ­
ised with the help of an international organisation which 
can provide some money for such purposes (UNESCO 
or EU). Specialisation of the participants was very high, 
considering that more than half of them were doctors in 
science. Young researchers (young by age) formed quite 
a large proportion of the members, due also to the re­
duced fees. Despite the proximity of the sea and nice 
weather, all the lectures were attended by more than 
hundred listeners, which showed the quality of the pa­
pers and their interesting topics.
The symposium was opened on Monday afternoon, 
May 26th, by the state secretary of the Ministry of Sci­
ence and Technology F. Demšar. Greetings were ex­
pressed by the organiser, representative of the Municipal 
Council, general sponsor, president of ATH, representa­
tive of the Ministry of Environment and Physical Plan­
ning, and by the president of the Karst Commission of 
the International Association of Hydrogeologists. On the 
first day only one paper (but lasting over one hour), the 
report on the Trnovsko-Banjška Planota project, was 
presented by P. Habič, the president of ATH. The next 
three days were fully occupied by professional papers, 
except one afternoon when the participants visited Kras 
(Classical Karst) and Škocjanske Jame caves. During 
three days, 42 papers and 23 posters were presented. 
Papers were grouped into six thematic sections: meth­
ods, surface water, unsaturated zone, aquifer, transport 
of pollutants and protection, aquifer characteristics, and 
modelling. It is impossible to mention all the papers and 
posters. Directly or indirectly all of them talked about 
water tracing, but were very different in details; from the 
papers which treated tracers to those which treated the 
study (by tracing methods) of waste water flow into the 
sea and pollution of groundwater by nuclear power 
plants.
About 30% of the participants (and 15% of the 
authors) were from Slovenia.
Their contributions were in the section on methods: 
Movement of bacteriophage and fluorescent tracers 
through underground river sediments (Bricelj & Mišič), 
Laboratory tracer experiments in carbonate porous me­
dia from Slovenia (Čenčur Curk, Obal, Kogovšek 
&Veselič); on the unsaturated zone : Water tracing tests 
in vadose zone (Kogovšek); on aquifers: Experiences in 
monitoring the Timavo river (Classical Karst) (Cucchi, 
Giorgetti, Marinetti & Kranjc), Properties of underground 
water flow in karst area near Lunan in Yunnan Province, 
China (Kogovšek, Liu & Petrič), Preliminary results of the 
submarine outfall survey near Piran (northern Adriatic 
Sea, (Malačič & Vukovič), Water balance investigations 
in the Bohinj region (Trišič, Bat, Polajnar & Pristov), Ad­
vanced methods of tracing in several Slovenian karst 
aquifers by using the natural light isotope characteristics
(Pezdič), On the role of clay-carbonate reactions in the 
speleoinception - advanced theory of the earliest stage 
of karst channels formation (Pezdič & Šušteršič); on 
pollutant transport and protection: Agriculture - Poten­
tial polluter of waters in karst region in Slovenia 
(Matičič), Development of a tracer test in a flooded 
uranium mine using Lycopodium clavatum  (Wolkers- 
dorfer & Trebušak & Feldtner). The papers prepared by 
Italian, German and Chinese participants in co-ope­
ration with Slovene authors proved that Slovene 
researchers are involved intensely into the international 
research sphere.
The symposium was also an opportunity to acquaint 
foreign7 participants with karst in Slovenia, focused upon 
karst waters and the results of Slovene field research, 
which was achieved through the excursions. For the 
participants from Slovenia, the main topic of the excur­
sions were problems of karst water protection. The high­
est interest was shown for the Trnovsko-Banjška Planota, 
where the test area of the project was shown and ex­
plained. On the way through Nova Gorica, the partici­
pants visited the headquarters of the general sponsor 
HIT. The second excursion was devoted to the upper 
Ljubljanica river basin focused upon karst poljes, the 
test area of the 3rc* SW T (1976). The third excursion led 
the participants to the less known part of Slovene karst, 
to the karst of Dolenjsko in the basin of the river Krka.
Additional activities have to be mentioned, too: 
presentations, exhibitions, selling of literature and in­
struments, organisation meeting (10th ATH meeting), 
and the programme for accompanying persons. In the 
closure of the symposium, C. Leibundgut, the president 
of the International Committee on Tracers of the Inter­
national Association of Hydrological Sciences, made a 
short summary of the expert part of the symposium, in­
cluding the trends of the future activity of the ATH. The 
symposium was closed by R. Tavzes, the state secretary 
of the Ministry of Environment and Physical Planning.
For the moment it is too early to evaluate the success 
of the symposium; we have to wait for the remarks and 
published reports of the participants. Taking into ac­
count their number, the professional and organisation 
work done, the published material (1 0 0 0  pages), the first 
responses of the participants and of the parent organisa­
tion - ATH - it is possible to say that the symposium suc­
ceeded as a professional event. Last but not least we 
must not forget the excellent technical assistance by the 
Meridiana agency and its specialist N. Zalar, as well as 
the Hotels Emona Convention Centre. The work and the 
money spent for the symposium must not be regretted. 
The question, however, how we w ill be able to make 
use of the new knowledge and the new perceptions is 
yet another problem.
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