Hui Hon began piling works at the Yuen Chau Kok site in February 1998 using a vibrator that did not have sufficient force to drive the temporary casings down to the founding level required by the contract. On top of this, Hui Hon were coming up against a number of soil problems.
Two months later, in an attempt to speed up the work, Hui Hon replaced the vibrator with a Bauer BG 40 drill rig, a machine with greater capacity. However, because suitable parts were lacking, this machine could not be used at full power. Nor was Hui Hon mastering the inherent geological problems. The progress of works was falling further and further behind schedule.
The problem was aggravated by the fact that not enough temporary casings were available to permit the construction of several piles at the same time.
So, in a totally misguided and unscrupulous attempt to deal with these issues, the directors of Hui Hon decided not to install the temporary casings right down to the proposed founding level. Where the shaft walls lacked temporary casing support, they collapsed and the shaft caved in.
In an attempt to arrest this soil collapse, Hui Hon purchased quantities of the proprietary soil stabilizer Super Mud to reinforce those pile shafts without installing temporary casings. The use of Super Mud was not in the method statement for the works. Given that the length of pile shafts without temporary casings extended from 5 m to 25 m, the Super Mud served little useful purpose.
In mid-June 1998, Hui Hon was troubled by financial problems and stopped using Super Mud. Although construction problems were mounting, Hui Hon continued to ignore them and forge ahead because the contract stipulated a fine of $170,000 per day for any work delay. Since the soil collapse situation was never improved, the depth of many of the pile shafts was reduced, and as a result the related piles were shorter than stipulated.
Faced with a project riddled with problems, major delays and the prospect of a huge fine, Hui Hon took the final step of resorting to a number of blatantly illegal acts that they thought would cover up the non-compliant piling works.
Two ex-directors of Hui Hon had assigned a site agent to monitor the Yuen Chau Kok piling works. He was responsible for submitting reports to HD about construction methods, implementation plans, proposed pile lengths and actual pile lengths after installation. This man was an employee of Hui Hon who had previously worked on other piling projects for the company.
The site agent had three subordinates: a foreman, a site foreman and an assistant engineer, all of whom were employees of Hui Hon. The assistant engineer was later transferred from the Yuen Chau Kok site to another construction site, and the vacancy was filled by an engineer who had only just graduated.
In early September 1998, Hui Hon claimed that the piling works for two of the buildings at Yuen Chau Kok had been completed. Between March and September 1998, Zen Pacific had paid $17 million to Hui Hon in project fees. Since it was clear that Hui Hon would not be able to complete the remaining works on schedule, Zen Pacific took over the work on 23 September 1998 but continued to employ the very same Hui Hon construction team to carry out the piling works for the remaining three buildings.
On 19 December 1998, within nine months after Hui Hon had commenced the works and Zen Pacific had taken them over, Zen Pacific informed HD that the piling works for all five buildings were complete. Three days later, another contractor started the construction of superstructure on top of the piled foundation. HD paid Zen Pacific $57 million as the project cost.
Even when the superstructure of the two buildings had each reached more than 30 storeys in height, no one had discovered the buildings were resting on noncompliant piling. The material evidence had been well and truly buried.