The Health and Safety Executive visited the site in February last year following complaints from local residents.
They complained about debris falling from upper storeys and of the danger to workers being left without any protection from falling while working at height.
Eze Kinsley, the developer in control of workers at the site, verbally abused the HSE Inspector who had to return with Essex police officers later to serve prohibition notices requiring an immediate stop to unsafe work at the site.
Kinsley reacted strongly to this, physically assaulting the inspector.
After further reports that work had not stopped, the HSE issued a further prohibition notice in April 2013, which was breached within just one hour of being served.
Kinsley, of Edgware, Middlesex, was prosecuted by the HSE at Colchester Magistrates’ Court.
HSE’s investigation found that there were no safety measures in place to prevent injury to workers from debris falling from height and that there was also a real risk of injury to members of the public using the road and pavement next to the Parkeston House site.
Kinsley was found guilty of assaulting an inspector from HSE at a separate court appearance.
HSE Inspector Jonathan Elven, said: “Although no one was injured as a result of the woefully inadequate working practices this is nevertheless a serious case.
“The working conditions on this site were truly appalling with absolutely no provision for workers’ safety.
In addition, the repeated breaching of prohibition notices – without any attempts to put right the reasons why work had been stopped – put workers and the general public at serious risk.
“Mr Kinsley refused to accept that he had a responsibility to make sure people who worked for him, and any member of the public living or working near his site, were not subjected to unnecessary risks – and vigorously and violently resisted all attempts to make him take actions to protect them.
“Putting safe working practices in place is often simple and inexpensive and, where this doesn’t happen, the costs, both financial and personal, can be immense.”