A Nigerian energy company said it was paving the way for the construction of one of the largest natural gas pipeline grids in the region. Oando announced it would expand natural gas infrastructure in Port Harcourt in the country\'s Niger Delta. The company plans to update and expand the gas infrastructure the city\'s industrial sector, paving the way for one of the largest gas pipeline grids in the region, the Platts news service reports.Nigeria has the eighth largest natural gas reserves in the world with an estimated 185 trillion cubic feet. A significant portion of that remains untapped, however. Royal Dutch Shell admitted last week it was responsible for two oil spills in the Niger Delta. The Bodo community in Nigeria filed a class-action lawsuit in London for an oil spill in the Niger Delta. That suit involves a leak believed to be from a pipeline that dumped crude oil into the Bodo creek for about four months in summer 2008. Shell said it didn\'t know of the problem for several months.The United Nations estimated that at least 6,800 oil spills occurred in Nigeria from 1976-2001. Shell said some of the spills were the result of sabotage of national pipelines.