In der Nähe von Riga gibt es ein etwa 100 Jahre altes Munitionslager durch das die Rail Baltica gebaut wird. Das Gelände gilt als munitionsbelastet und muß beräumt werden. Hierzu ein Artikel:
Rail Baltica to scan up to 4 ha large former military area in Latvia to identify unexploded ordnance
The Rail Baltica joint venture RB Rail AS has launched a new procurement with aim to identify unexploded ordnance (UXO) and carry out geotechnical works in the former Cekule military area in Latvia. The contaminated area is in Stopiņi parish, next to State road A4, approximately 20 km from Riga. The territory is planned to be used for placing Rail Baltica’s main line on section ‘’Vangaži-Salaspils-Misa’’.
Cekule area where warehouses of the Latvian National Armed Forces were located in 1920s is contaminated with unexploded ordnance. During WWII, the warehouses were blown up, scattering the munition all throughout the area. Later, around 1-2 meters of soil was backfilled on this area to make it safer. The area saw continual military use up until the USSR army left the Latvian territory in 1994.
Now the territory is covered by trees and underbrush, and according to local planning documents is considered as a forest area. The Latvian National Armed Forces are gradually cleaning the territory by carrying out explosive ordinance disposal training. The proposed Rail Baltica railway line crosses the Eastern part of this area, where previous scanning efforts have detected approximately 1 to 10 possible UXOs per 100 m2.
Currently, the land plot is considered to be dangerous, and no geotechnical investigation works can be carried out until the territory is cleaned. This creates the necessity to organize the first phase of UXO location and removal already during the design phase.
A magnetometer, gradiometer and geo-electrical survey methods will be used to identify the UXOs. The magnetometer and gradiometer measure the earth’s magnetic field and detect changes in it due to the presence of metallic objects in the ground. The gradiometer measures the change in the field, increasing the accuracy of the magnetometer. The mapping must be done with an individual, mobile equipment, but in larger areas there is a possibility to use a drone. As a result, a material with magnetic field anomalies will be obtained, with an accuracy of up to 1 cm. After mapping the UXOs, it will be possible to assess the resources and time required for the territory clearance allowing to proceed with geotechnical investigations’ works. The territory to be addressed under the works being procured is approx. 4 ha, while a territory up to 10 times larger will be cleaned as part of construction works.
The activity is financed by the EU Connecting Europe Facility and the Latvian State budget.
More about the tender: https://www.railbaltica.org/tenders