norway-sarpsborg: excavating work./ alvim treatment plant - b5 preparatory work./ this procurement is for contract b5 - preparatory work that will facilitate the execution of new gas installations (contract m4, as well as the largest construction contract b1). the contract includes the following main work: excavation and piling for a process building gas tanks, and garage building. casting bottom plates, demolition work, establishment of a site road, and development of the rigging area. securing area stability. pressing pipes under the railway and laying water and sewage pipelines in the ground.