The recording device was installed by the Waste Partnership for Buckinghamshire as part of its work with the Environment Agency and Buckinghamshire County Council.
It has helped gather evidence of people illegally dumping waste in Trenches Lane, Langley, near Slough.
But officers viewing the tapes noticed the driver of a green Ford Focus pulling up at the location four or five times a day and acting suspiciously.
Keith Wayne Chambers, 37, of Wembley, was subsequently arrested and charged with possession of crack cocaine with intent to supply, and possession of a prohibited weapon.
Waste Partnership chairman Margaret Dewar said: We were happy to alert police to this mans activities but this was an unusual case. Our cameras have also gathered evidence on people fly-tipping, and we want to emphasise our determination to stamp out illegal dumping in the area.
Detective Constable Jason Kew added: This is a good example of partnership working between police, local authorities and other agencies.