Contributors: V. Gregorauskienė R. Kanopienė J. Lazauskienė A. Pačėsa J. Satkūnas I. Virbickienė

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1 EXCURSION GUIDE Contributors: V. Gregorauskienė R. Kanopienė J. Lazauskienė A. Pačėsa J. Satkūnas I. Virbickienė

2 CONTENT VILNIUS TOUR PROGRAMME 1. Location of the Vilnius tour excursion sites Lithuania: some historical facts Vilnius City: the trace of a history Pučkoriai outcrop Trakai City: the ancient ducal residence Kernavė: the first capital of Lithuania? 88 EXCURSION TO IGNALINA NUCLEAR POWER PLANT 1.. Programme of the excursion to Ignalina NPP Scheme of the excursion route and stops Stop No 1. Ignalina Nuclear Power Plant Stop No 2. Ignalina seismic monitoring station site Stops No 3 4. Ladakalnis hill and Aukštaitija National park Annex. Geology of Ignalina NPP region 100 (V. Marcinkevičius et al., 1995) 83

3 Prrogrramme off tthe excurrsiion tto IIgnalliina NPP September 12, 2007, Wednesday 7.30 Departure from the E-Guesthouse Hotel. (Ševčenkos 16, Vilnius) Arrival to Ignalina NPP Stop No 1. Visit to Ignalina NPP Lunch at Ignalina NPP. (Participants leaving this day departure to Vilnius) Stop No 2. Ignalina seismic monitoring station. Cold snacks Site seeing trip in Aukštaitija National Park Stop No 3. Ladakalnis hill Stop No 4. Lūšiai Lake and Palūšė village Departure to Vilnius 90

4 Scheme of the Excursion route and stops 1. Ignalina Nuclear Power Plant (Ignalina NPP). 2. Ignalina seismic monitoring station. 3. Ladakalnis hill (Aukštaitija National Park). 4. Lake Lūšiai and Palūšė village (Aukštaitija National Park). 91

5 Sttop No 1 Ignalina Nuclear Power Plant The Power Plant is constructed on the southern coast Drūkšiai Lake. The area of Drūkšiai Lake is 44.8 sq. km (Fig. 1). The nearest to the Power Plant large cities are Vilnius, located in 130 kms ( inhabitants), and Daugavpils in Latvia, located in 30 kms ( inhabitants). Fig. 1. Location of Ignalina NPP Design and engineering geological investigations prior to construction started and in 1974 on December 31, 1983 unit 1 commissioned. Originally, unit 2 was to be launched in 1986, but commissioning postponed to the year 1987 because of the Chernobyl accident. On April 26, 1986, following the Chernobyl accident, at the request of the government of Lithuania, the government of the USSR suspended the construction of unit 3. In 1989 the construction of unit 3 discontinued altogether. It took 11 years to build the world s most Powerful Nuclear Plant. The construction of the Ignalina NPP necessitated: 142 km of roads, 50 km of railway, 390 km communication lines, 334 km of electricity lines, 133 km of sewerage lines, 164 km of thermal lines. Three million 544,00 m 3 of concrete and reinforced concrete and tonnes of reinforcement were used for the construction. The INPP contains RBMK 1500 water cooled graphite moderated channel type power reactors. The RBMK 1500 reactor is the largest power reactor in the world. The thermal power output of one unit is 4800MW; the electrical power capacity is 1500 MW. Ignalina NPP generates about 80% of electricity consumed in Lithuania. 92

6 The important area of a nuclear power plant safety is storage of the spent nuclear fuel. From the beginning of Ignalina NPP operation the spent nuclear fuel is stored under a layer of water in special pools placed in the same buildings, as reactors. It is a temporary way of storage, therefore the international competition for the spent nuclear fuel storage was announced, the German company GNB gained the victory in which. In 1993 Ignalina NPP and the German company GNB signed the contract on the delivery of 20 CASTOR and 40 CONSTOR steel containers for the storage of the spent nuclear fuel. The total cost of the contract was about 30 mln DM. The first container CASTOR was sent to the storage site constructed nearby Ignalina NPP on May 12, Some part of the spent nuclear fuel has already been placed in all available containers of CASTOR type (20 containers) and was taken to the spent nuclear fuel storage site. The container is located on a special platform at the site. One of the important works related with the future decommissioning of INPP Unit 1 is the unloading and location of the spent nuclear fuel in the storages. The Ignalina NPP experts affirm that the available number of the containers will not solve the problem of the spent nuclear fuel, basing on the evaluation that in the case of Unit 1 shutdown at the end of year 2004, and Unit 2 shutdown in year 2010, 350 containers in addition would be required. The spent nuclear fuel can be stored in containers CASTOR and CONSTOR for 50 years, then it is necessary to take it out to the final burial place, but in Lithuania such place is not stipulated yet. Under the pressing of EU Lithuania made a commitment to prepare for the decommissioning first unit of Ignalina NPP by 2004 and the second unit has to be ready for decommissioning by 2009 under the sufficient financing support. Both units of Ignalina NPP are of the same type as Chernobyl one e.g. according the western standards is considered as unsafe. 93

7 Sttop No 2 Stations of seismological monitoring system ( Ignalina seismic monitoring station) The territory of Lithuania and adjacent areas in the Baltic Region feature a low seismic activity due to the Earth crust of Early Precambrian consolidation and significant distances to the active tectonic zones. Nevertheless, according to historical and instrumental data, 45 local earthquakes of small and moderate size ruptured since 1616 to Local earthquakes of maximum expected magnitudes (more than 5) can generate shaking of the Earth surface with intensity VII or even VIII. The first instrumental seismological observations in Lithuania were initiated in 1970 when Vilnius seismic station (VIL) was founded (Fig. 2). Three analog long period (T=25 s) and three short period (T=1.5 s) seismometers were installed at Vilnius station. Collected data were processed and stored in Moscow University until Later on, maintenance of station and routine data processing was undertaken by Institute of Physics of Lithuania. 450 distant and regional seismic events were reported in seismic bulletin of Vilnius seismic station during the period Phase readings, amplitudes and periods were defined in routine processing. Distances from the epicentres to Vilnius station were calculated and reported in the bulletin. No local events were registered in Vilnius seismic station. Probably, high level background noise at this site reduced resolution of short period seismometers inhibiting detection of small local events. Operation of Vilnius seismic station was suspended in the beginning of (SLTR) Fig. 2. Seismic station s network in Lithuania. Bounded triangles four existing seismic stations of Ignalina NPP, red squares two new GEOFON network broad bend seismic stations foreseen to be installed in

8 The fist comprehensive study of seismic activity of Lithuania was carried out in 1988 as a part of re examination of safety of Ignalina Nuclear Power Plant (INPP). Twenty two outstanding experts of the Soviet Union came to conclusion that seismic hazard was assessed not enougth when designing INPP despite local and international regulations insisted on it. In order to improve the situation the experts proposed to install seismic network and monitor local seismicity. The group of industrialised states G 7 approved the plan of actions improving safety of Soviet nuclear reactors in Fund named ʺAccount of Nuclear Safetyʺ provided irrevocable loan for Lithuania to renovate safety systems of INPP in One of the projects considered installation of a Seismic Alarm System, SAS. This system was designed to issue alarm when damaging seismic wave approaches the INPP. The SAS was complemented with the Seismic Monitoring System, SMS. The SMS was designed to collect data of local seismicity and dynamic behaviour of structures of INPP. The SMS consists of number of accelerometers deployed inside buildings of INPP (Fig. 3) and four vertical short period seismometers installed in boreholes with at the depth of 30 m located at a distance of ~30 km to the INPP (Fig. 4). Fig. 3. Deploymet of accelerometers of SMS at INPP The signals of the seismometers are transformed to digital form and telemetered continuously to the control center in INPP. The control center records data of seismometers if local or teleseismic event is detected. SAS and SMS including four outside seismic stations on territory of Lithunia were installed in June of 1999 (Figs. 1, 2). Two more seismic stations had to be installed on the territory of Latvia and Belarus. 95

9 Fig. 4. Seismic station of seismic network of Ignalina NPP Short period seismometer of vertical component is installed in borehole at a depth of 30 m at each station of SMS (Table 1). Some equipment of SAS is installed at the same sites. The signals of the seismometers are digitalized and sent via radio link continuously to the control center at INPP. The control center records data of seismometers if local or teleseismic event is detected. Besides remote seismometers, the SMS includes number of accelerometers inside of the building of power plant aimed to register responses of the structures and equipment (Fig. 3). Main technical parameters of seismic stations of Ignalina NPP Equipment of the same type and configuration is installed on all four seismic stations. Seismic sensor: Uniaxial Borehole seismometer. Manufacturer: Guralp Systems. Model: CMG 40V 1. Loaded generator constant: 3000 V/(m/s). Natural period: 1 Hz. Damping ratio: 0.7. Depth of borehole: 30 m. Digitizer: 24 bits. Sampling rate: 100 Hz. Co ordinates of the seismic stations of Ignalina NPP Seismic station Code Co ordinates (deg) N E Altitude (m) Type of sensor Components Didžiasalis IDID Seismometer Z Ignalina IIGN Seismometer Z Salakas ISAL Seismometer Z Zarasai IZAR Seismometer Z INPP Accelerometer Z, N, E 96

10 At the same time with establishment of SMS of INPP, Lithuanian Geological Survey (LGT) took responsibility to process, analyze and store seismological data of SMS and, simultaneously, the project of seismological monitoring was lounched in 1999 (recently prolonged until year 2010). Data from INPP to LGT are transferred via Internet; SEISAN software is used for data processing. Identification of seismic events comprises the first step of routine of data processing. Then onsets of seismic waves and maximum amplitudes are read and co ordinates of events are estimated. Calculated epicenters are compared with ones provided by the other seismological agencies. The processed data of SMS, overviews of seismological bulletins of NORSAR and Seismological institute of Helsinki University (HU) related to Lithuania and some other results were presented in the annual seismological bulletins of Lithuania and internal reports. A special web page of seismology ( is introduced in the web site of LGT. Copies of the seismological bulletins are sent to ISC and EMSC regularly. The seismic activity of Ignalina NPP area Data of seismological monitoring of Lithuania seemed to support an idea of the low seismic activity of Lithuania and adjacent territories. Nevertheless, Thirteen historical earthquakes took place within the radius of 250 km around the Ignalina NPP. Intensity of some of those events reached 7 points (12 grade MSK 64 scale). The Daugavpils and Gudogai earthquakes are the closest to the Ignalina NPP registered events that took place in 1908, as well as Koknese earthquake of These seismic events are related to the Daugavpils, Vilnius, Ašmena and Gulbene large scale seismogenic faults. The Daugavpils earthquake is situated 35 km from the Ignalina NPP, the depth is of 2 3 km, intensity is 7 points (MSK 64 scale). The Gudogai and Koknese earthquakes were registered at the distance of respectively 125 km and 135 km from the Ignalina NPP, the depth is estimated as much as of 9 km and 12 km, the intensity reached 7 grades. Moreover, earthquakes of moderate size (M > 5.0) can shock the region occasionally. Only a few local seismic events were recorded by the SMS during the five and a half year one seismic event was recorded at the station ISAL September 4, The epicenter was found on a distance of ~90 km away from the station, however, no localization was possible as the event was recorded by the single station. Neither seismic station of neighboring countries nor Scandinavian seismological networks have recorded this event. An earthquake of magnitude of 3.1 was recorded on December 18, The epicenter was located in the Baltic Sea southwards from Gotland Island. A few explosion events were recorded by SMS as well. Despite SMS was designed to monitor local seismic activity, approximately 100 distant seismic events were registered by the system each year. 97

11 Sttops No 3 4 Ladakalnis hill and Aukštaitija National Park Ladakalnis, hill famous picturesque place in the national park. The hill was formed about years ago by the flow of melt water of last glacier. Melt water formed several morainic crests with sandy hills in the margins of them. The largest crest is Šiliniskiai (leghth about 5 km, hight 50 m), and Ladakalnis hill is the part of it. The highth of the hill is 35 m above Linkmenys Lake surface. Lithuaniaʹs first national park Aukstaitija National Park was designated in 1974 and covers an area of hectares in the regions of Ignalina, Utena and Švenčionys. Over 70 per cent of its territory is pine stands, including the ancient woods of Ažvinčiai, Minčia and Linkmenos. Some of the pine trees in Ažvinčiai wood are over 200 years old and the oaks of Trainiskis, Kaltanėnai and Varniskiai are the remains of the ancient oak tree forests that once covered large territories here. The park represents a picturesque forested and hilly terrain abounding in lakes and having ethnographic villages; it contains quite a lot of other cultural monuments. Scattered among the woods and hills are some 100 smaller and larger lakes, often interconnected by rivulets and streams. The largest of them is Lake Dringis (721 ha). Lake Tauragnas, the deepest in Lithuania (60.5 m deep) is also here. The Baluošas features seven islands, one of which has a little lake of its own, feeding the Baluošas waters through a small stream. Of some thirty rivers on the territory of the park, Žeimena is the most beautiful, although the smaller ones Kriauna, Lukna, Buka, Šventelė, Stregžda are no less attractive to tourists, linguists and ethnographers alike. The woods, marshes and meadows of Aukštaitija National Park abound in rare plant species, including a number of plants that are listed in the Red Data Book of Lithuania and are protected as endangered species. The woods of the park are the domain of elk, deer and wild boar. The lakes and rivers, too, are rich in wildlife, from Canadian mink to a variety of birds that can bring quite a few exciting moments to a devoted birdwatcher. 98

12 The parkʹs territory embraces some 80 settlements and villages, some of which have retained not only their old original layout but also archaic wooden farm buildings and other structures. Palūšė village, which is the tourist centre of the Aukštaitija National Park, was first mentioned in written sources in It still boasts an octagonal wooden church dating back to Palūšė is the starting point of most of the tourist routes, both shorter and longer walks and a rowing boat route along a system of lakes and streams connecting them. (Information about the National park was obtained from website Lake Lūšiai Žeimena River 99