Technical Excursions

The conference participants can choose from five site visits to the underground structures in and around Prague organised on Wednesday morning, 31 May 2023.

  • Site visit A – Line D of the Prague Metro – excavation of access tunnels in the direction of Pankrác D Station
    The maximum number of participants for Site Visit A is 20.
  • Site visit B – Line D of the Prague Metro – Pankrác – Olbrachtova Section + Connection C-D
    The maximum number of participants for Site Visit B is 20.
  • Site Visit C – City of Prague Urban Traffic Control Centre (UTCC Prague)
    The maximum number of participants for Site Visit C is 20.
  • Site visit D – Richard Radioactive Waste Repository
    The maximum number of participants for Site Visit D is 16.
  • Site visit E – Rudolph Adit + old wastewater treatment plant
    The maximum number of participants for Site Visit E is 20.

Application for the Site Visit

When registering, please tick the selected site visit on the online registration form (the excursion registration form will be available from 20 January 2023).

English interpretation of all site visits will be provided for foreign participants.
 

Excursion A – Line D of the Prague Metro – excavation of access tunnels in the direction of Pankrác D Station

The Metro Line D construction in Prague began with the construction of Section I.D1a in the Pankrác – Olbrachtova section with a track connection to the existing Metro Line C and a transfer to the existing Pankrác C Station. The entire tunnelled part is located under the existing built-up area, so the tunnelling requires additional measures in the form of chemical sealing grouts, compensatory grouting and other support elements associated with such a complicated construction.

Pankrác D Station is designed as a single-vault excavated station with a transverse profile of approximately 350 m2 with three escalator tunnels. The Pankrác Station excavations take place from the PAD1b construction site, which is located at the exit from 5. května Street to Na Strži Street in Prague 4. As part of an engineering-geological survey, a shaft with a net cross-section of 19.2 m and a depth of 27.5 m was dug at this location. During the implementation of the I.D metro, a 200-m-long access and ventilation adit was subsequently driven, which at its end is divided into two branches, Branch A towards the air-conditioning machine room and Branch B towards the future dismantling chamber, where the excavations are currently interrupted.  The 50-m-long air-conditioning machine room itself is connected to the tunnelled Branch A. Behind the air-conditioning machine room, there is also a 46-m-long excavated technological link, which is connected to the turning tracks downstream of Pankrác D Station, where excavations are currently underway – first towards Pankrác D Station in a planned length of approximately 70 m and then back towards the dismantling chamber at Branch B of the access and ventilation adit with a planned length of approximately 120 m.

Excursion B – Line D of the Prague Metro – Pankrác – Olbrachtova Section + Connection C-D

The construction of the new Line D in Prague began with the Pankrác – Olbrachtova section including a track connection to the existing Metro Line C and Pankrác C Station. Access to the underground is made possible through a shaft made of re-bored piles with a depth of 36 m and a diameter of 25 m. From this shaft, a double-track line tunnel is excavated towards Pankrác Station with a length of 218 m, which is followed by an access tunnel and a so-called bottom adit (drift) of the future Pankrác D Station (the lowest partial cut of the future single-vault station). On the opposite side, in the direction of Olbrachtova Station, a double-track tunnel with a length of approximately 200 m is driven, and then the route branches into left and right single-track tunnels with a length of approximately 270 m. At the point of transition from the driven double-track tunnel to the right-hand single-track tunnel, there is an underground driven cavern for the future split – a branch to the so-called Connection C-D with a length of approximately 470 m, connecting the existing Line C with this newly built section of the Line D route. The entire tunnelled part is located under the existing built-up area, so the tunnelling requires additional measures in the form of chemical sealing grouts, compensatory grouting and other support elements.

Excursion C – City of Prague Urban Traffic Control Centre (UTCC Prague)

Tour participants are to meet at 9:00 am in front of the UTCC building. The tour itself will last 1.5 hours.

UTCC Prague is the competent control centre for traffic in road tunnels in the central part of Prague and is the highest level of the telematic transport system operated in the City of Prague. UTCC is currently located in the building of the Central Dispatching building for public transport, in Prague 2. It is operated by officers of the Police of the Czech Republic. This specialized facility also collects and processes transport information on traffic in the delineated section or area of the road network, transport data from telematic applications in the various sensor cross-sections, technological information on the state of operation of various pieces of equipment and warning alerts on critical situations.

The excursion will focus on a tour of the dispatching centre and information concerning the monitoring and management of traffic in tunnels in the central part of Prague.

Translation into English will be provided for foreign participants.
The maximum number of participants for Excursion C is 20.

Excursion D – Richard Radioactive Waste Repository

Departure from Clarion Congress Hotel at 8:00 am. The tour itself will last 2 hours. Return to Clarion Congress Hotel at 1:00 pm.

The extensive underground mines of Richard I, II and III, which stretch out in the hills above the North Bohemian town of Litoměřice, have a rich history, not always focused on mineral mining. From the first half of the 19th century, limestone was quarried under the peak of Bídnice. The limestone layer in this area is located approx. 70 to 80 metres below the surface and is about five metres thick. Such an environment is optimal for the extraction of this mineral, thus three separate limestone quarries were created here.

In the years 1943–1944, the Nazis selected this site due to secrecy for their underground factory for the company Auto Union A. G. Chemnitz (manufacture of components and parts for Maybach engines – type HL 230) and the company Osram. They gave the construction of the underground manufacturing facilities the code name Richard; sometimes the factory was also referred to as B 5. Working on the large-scale construction project were imprisoned miners, bricklayers, concreters, electricians, plumbers and other tradespeople. These were shipped in for the job from the work camp in Litoměřice, and some of them also from nearby Terezín. Only some of the manufacturing halls for Auto Union managed to be fully completed.

After the war, the underground space remained in various stages of construction, from fully completed manufacturing halls to corridors where expansion mining work was still just taking place. After all the equipment was carted off at the end of 1945, Čižkovice Cement and Lime renewed the extraction of limestone. Over the following 15 years, an extensive complex of tunnels building off Richard I were formed. The method of mining used was however much more expensive that an open quarry and extraction was terminated.

There were considerations on alternative manners of using all three mines as far back as the 1950s. In 1959 the first official proposal for utilizing the Richard II mining complex to store radioactive waste was made. Five years later, in 1964, this plan became a reality.

Another important milestone in the history of the Richard repository is the year 1976. This was when the Czech Central Mountains Protected Landscape Area was formed. This area included the territory of all three Richard mines, including Richard II, where the eponymous radioactive waste repository has been functioning for over 50 years. Every year several hundred casks of waste are shipped to the repository and stored there. This is institutional waste formed of discontinued radioactive emitters (fire alarms, level gauges, etc.), contaminated rubble, plastic, paper, etc.

The total volume of space used in the Richard II mine exceeds 19 000 m3. The capacity of the storage chambers is 10 250 m3, which is currently about 70% full.

Translation into English will be provided for foreign participants.
The maximum number of participants for Excursion D is 16.

Excursion E – Rudolph Adit + old wastewater treatment plant

Departure from Clarion Congress Hotel at 8:00 am. The tour itself will last around ě hours. Return to Clarion Congress Hotel at 12:00 noon.

The Rudolph Adit is a 1102 m long historical underground work. It has an oval profile, with a height ranging from 2 to 4 metres and a width of 80 to 150 cm. The average temperature inside is around 11 degrees. The route of the tunnel leads around 45 m below ground level.

The adit, which from the beginning served to connect the ponds in the Royal Game Reserve to water from the Vltava, was built in 1584–1593 on the orders of Emperor Rudolph II. Construction of the adit was entrusted to the chief bergmeister Lazar Ercker von Schreckenfels, who was helped by chief mine surveyor Jiří Oeder of Ústí.

Completion of work on the adit was managed by Ercker's successor Van der Vam Kojas. The whole work cost 66299 threescores of Groschen. Where the rock was not firm enough, the corridors were reinforced only with timber. In the years 1636–1639 the adit was bricked by the portals, and later to a greater extent as well. In 1711 a wooden boardwalk was built along its whole length. Over its existence, the walls of the adit have collapsed inside many times and the corridor thus had to be cleared out. In the 1950s the bottom of the tunnel was tiled with gutters.

The old wastewater treatment plant in Prague – Bubeneč is an important document in the history of architecture, engineering and water management. It was built in the years 1901–1905 as the last link in the systematic sewer network in Prague. It served to treat the majority of wastewater in Prague up until 1967, when the Central Wastewater Treatment Plant was put into operation on the nearby Císařský ostrov. The project for the sewer system and design of the technical parameters for the plant were drafted by the civil engineer of British origin Sir William Heerlein Lindley.

Translation into English will be provided for foreign participants.
The maximum number of participants for Excursion E is 20.