NSW Rural Fire Service Commissioner Shane Fitzsimmons has apologised to Blue Mountains residents who are returning to their ruined homes, saying firefighters did their best. Fire authorities are beginning to scale-down their enormous eight-day fight against bushfires that destroyed more than 200 homes across the state last week. The Rural Fire Service considered Wednesday to be a critical day due to the weather, and in the Blue Mountains it advised all schools to be closed and hundreds of residents to leave. Mr Fitzsimmons on Thursday thanked all involved in the fight. He also apologised to people returning to ruins, particularly at Springwood, in the Blue Mountains, where 193 homes were lost. "On behalf of the firefighters who are doing it so tough up there, we do apologise and regret that we weren't able to save everything," he said. We are very acutely aware, because our teams are embedded in those local communities, particularly in the likes of the lower Blue Mountains, through Springwood and Winmalee, there has been so much damage and destruction and people have lost everything. They did their best, and they will continue to do their best. They will work with you, as will indeed the broader community, work with you, each and every one of you, as you seek to rebuild and gather yourself together and move on from this terrible, destructive and damaging fire situation that we've seen. While it wasn't the most destructive fire, Mr Fitzsimmons said one of the most troubling in the Blue Mountains was the State Mine fire, an enormous blaze that has burnt out more than 46,000 hectares of bush. There were fears the fire would merge with another in the area and spawn a "mega fire," forcing firefighters to adopt aggressive tactics, he said. An RFS report on Wednesday found the fire started as a result of explosives testing on Department of Defence land. Mr Fitzsimmons defended his agency's response to the still-burning blaze, which destroyed three homes last week. "The fire occurred on a live firing range ... you can't send firefighters or fire trucks into a live firing range," he told reporters. Nor can you put aircraft above or into close proximity to assist in water bombing. Firefighters were working in and around the army range with a view to try to deal with that fire the day before it ran. He said conditions last Wednesday didn't necessitate total fire bans and "activities on live firing ranges are a matter of routine." He said he didn't know how many hours the fire had burned for before the RFS could work on it. Mr Fitzsimmons earlier explained that Defence was a partner for the RFS who "worked intimately" with local committees and authorities on bushfire management. Sixty-five fires are still burning across the state, 24 of them uncontained. The State Mine fire is one of four still at the "watch and act" level of alert.