A whopping £20 million could be borrowed to deal with crumbling concrete at a council headquarters to make the building fit for use for the next 40 years. Medway Council’s Gun Wharf will get the huge investment to deal with reinforced autoclaved aerated concrete (RAAC), council papers say. A report that will be discussed at a cabinet meeting on Tuesday, February 13 will provide options to members about what to do with the authority’s HQ which has been largely closed due to RAAC being discovered. The concrete became national news in September last year when schools across the country were close…