Jemgum. The examination of the leak detected in the brine transport pipeline from the natural gas storage facility Jemgum to the discharge point in Rysum has been completed. According to the inspection this was the only damaged area of the 43.5-kilometre pipeline. However, a 4.5-kilometre-long pipeline section affected by corrosion will be refurbished as a precaution to ensure further damage is prevented. Rehabilitation work on the piping section between Riepster Hammrich and the Jade-Ems Canal and at two other locations between Pewsum and Twixlum is planned between the end of April and July 2014 following consultation with the owners of neighbouring properties. After completion of the repairs, requisite acceptance testing by an independent expert and approval by the State Authority for Mining, Energy and Geology (LBEG), the pipeline is expected to be returned to service as early as August 2014.
To establish the cause of the leak, the pipeline was cleaned along its entire length and checked by independent experts using the ‘smart pigging’ method. This procedure involves the use of ultrasonic inspection equipment to check the pipeline for material damage and signs of corrosion. "When analysing the leak and considering all issues involving safety, our primary concern was that accuracy and safety should take precedence over speed,” astora project manager Arkadius J. Binia explains. "For this reason we set great store in cooperating closely with the representatives of the relevant authorities, the TÜV-Nord specialist and external experts throughout the examination in order to create the basis for the continuing safe operation of the pipeline. In addition to regular checks, an extended monitoring scheme will be introduced to guarantee that the brine transport pipeline is fully operational and safe,” says Binia.
Brine temporarily transported by ship
The leak in the brine transport pipeline between Jemgum and Rysumer Nacken was discovered on 3 September 2013. As soon as it was detected, the project partners astora and EWE Gasspeicher immediately discontinued the brine transportation and informed the relevant authorities. Within 24 hours the damaged area – a crack about 13 mm long – was completely sealed off. The soil contaminated by the salty water was then disposed of in accordance with the relevant requirements. The cause of the crack was a highly unusual type of corrosion which meant that the damage was unforeseeable. Since suspending operation of the pipeline, astora has been using two high-safety vessels to transport the Jemgum cavern brine from the storage site to the landing pier at Rysum. The brine is then discharged into the North Sea at the approved discharge point on the Outer Ems River.
astora GmbH & Co. KG, based in Kassel, Germany, is one of the largest natural gas storage operators in Europe. The company maintains one of the largest natural gas storage facilities in Western Europe at Rehden in Northern Germany, which has a working gas volume of more than four billion cubic metres. In addition, the storage company also holds capacities in the second largest storage facility in Central Europe, located in Haidach, Austria. In order to secure natural gas supplies to Europe, the company is currently developing the Jemgum natural gas storage facility on the German-Dutch border.