The building suddenly came down last Tuesday killing Coleman and Company worker Michael Collings and trapping three of his colleagues.
The boiler house structure was being prepared for a blowdown scheduled for this weekend.
The families of the three missing people have now returned home from the site as the complex recovery operation continues.
Assistant Chief Constable, Scott Chilton, said: “The recovery of the bodies and site investigation will be a very complex operation and I envisage it will be many, many weeks before it is completed.
“I know that this makes it particularly difficult for the families involved, as they await the recovery of their loved ones.
“Our priority remains to return them to their families and we continue to support the families as needed.
“We are working closely with the Health and Safety Executive to establish the cause of the incident.”
Chief Fire Officer Dave Etheridge added: “Our thoughts very much continue to be with the families of those who have lost their lives and I would like to reassure them that we are doing all we can to return their loved ones to them.
“I believe the emergency service teams working on site are the best in the world and know they are using their experience and expertise to the limits.”
The missing demolition workers are buried beneath a mountain of rubble
Coleman and Company Managing Director Mark Coleman said: “It is now one week since this terrible accident and I would like to express our deep sorrow at this heartbreaking time for our colleagues, and their families and friends.
“Nothing can prepare you for, nor are there words to express, our devastation at the events of the last week.
“All our hearts go out to the family and friends of those who have died and are still, tragically, missing.
“At this time, our over-riding priority is to support those families affected by this terrible incident.
“I would like to take this opportunity to thank all the rescue and emergency services who rushed to the scene and brought with them world-class expertise in facing this unprecedented and hugely-challenging environment.
“The overwhelming support we have received from people who work for and with us – and above all from our client RWE – has been extraordinary.
“It has touched us deeply and we are extremely grateful for all the kind words and offers of practical help we have received.
“Finally, I would like to thank the media for their co-operation and ask them to continue to respect the privacy of the families involved and all those who are currently working on the site.”