The construction of a standby leg of the ESPO-2 system underwater crossing started on the right bank of the Amur River, Khabarovsk Region. The facility is being constructed to increase reliability of the pipeline system as it increases its capacity to 50 million tonnes of oil per year, RIA Vostok Media reports.
Design and survey works are completed; the builders have started working both on the ground and in water-bearing sections. The length of the siphon (an underwater pipeline section — ed. note) laid across the main riverbed is 2,785 metres. Besides the main siphon, 8 more siphons will be laid across distributaries, lakes and oxbow lakes in the floodplain of the river, with the length of a siphon ranging from 110 to 622 metres. It makes the standby leg of crossing over the Amur river one of the longest OTPUWCs in the system of Russian oil trunk pipelines.
The standby leg is 4 km longer than the existing one. This is due to the tasks the designers were facing: to ensure both process and environmental safety while bearing in mind the harsh temper of the big river.
“In 2013, Amur had a huge freshet. The water rise reached 8.08 metres. So, in designing the leg, all onshore facilities are placed one metre above that elevation. This is why the leg will be 34.5 kilometres long. In the standby leg operation — in onshore patrolling and maintenance — this section will offer particular hardships due to its highly water-bearing location. We shall use special equipment and watercraft for that,” said Artur Mufazzalov, Deputy Manager of the Oil Pipeline Operation Section at Transneft Far East.
It is no coincidence the work began in winter: it is easier to work on swampy sections of the pipeline route in the cold season. The workers need to clean the soil, dig a trench and weld pipes. Specialists carry out the work at any frosts, observing all process requirements for future safe operation of the facility and without inflicting damage on the environment.
“We faced the task of making the leg bypass the conservation sites, with plant species entered into the Red Book of Russia and Khabarovsk Region. During the design and survey works, we discovered the Amur cork tree, a herbaceous vine, paeonia obovata, whose habitats remained outside of the route,” said Leonid Tuboltsev, Head of the Environmental Safety and Rational Nature Management Section at Transneft Far East.
The standby leg creators made a provision for the local fauna as well. Since the work will be performed in the district of traditional roe deer migration path, special “silence days” will be introduced for that period so as not to scare the animals. And for the periods when chum salmon juveniles go down the Amur and then upstream for spawning, the environmentalists will enhance monitoring and will suspend the work if required. The major task is to avoid damage to the environment during the pipeline leg construction and operation. The measures taken during the laying of the main leg of the ESPO-2 underwater crossing have proved to be quite fruitful.
“In this section the professionals have only some 2 out of 11 km of pipes left to weld. We expect the welding to be finished by 10 March and will fully prepare the right bank for further operations prior to the mud season, i.e. by 1 April,” Aleksandr Sevastyanov, PMC ESPO’s Head of Construction at Site No. 18 of the OTPUWC across the Amur river, explained.
In spring, the builders will start laying siphons in small distributaries, backwaters and oxbow lakes. According to the plan, summer is the time for dredging the bottom for the leg in the main riverbed of the Amur, and in September specialists will lay the longest underwater pipeline section across the river. Using barges, they will pull 2,785 metres of the single-line welded pipeline over the bottom.