Rutland Trust PLC agreed Monday to pay 53.4 million pounds ($83 million) for the Thamesport deep-water container facility near London and an associate transport company.

Maritime Transport Services Ltd., the company that owns Thamesport, has outstanding bank debt of almost UK79 million. Under the terms of the sale, Rutland will repay the banks UK16.3 million and assume some UK36.1 million of debt, leaving creditors with a substantial loss.Rutland, an investment company that specializes in rescuing companies whose management has strong operational skills but a lack of financial expertise, plans to retain the same management team that originally worked together during the early development of Felixstowe, now Britain's largest containerport, before setting up Thamesport.

Thamesport, located some 35 miles east of London, cost more than UK100 million to develop and last year handled 145,000 containers. Major customers include Evergreen Line, Hapag-Lloyd and Neptune Orient Lines. Throughput this year is expected to reach 180,000, while up to 275,000 units could be handled using existing capacity.

The port is one of the most automated in the country. It has never been able to fulfill its early potential because of the abolition of Britain's restrictive dock labor laws in 1989 which removed Thamesport's competitive advantage over other ports. Bank debt expanded and eventually 11 creditor banks agreed a restructuring deal in 1993, under which UK95 million out of Thamesport's total debt of UK170 million was converted to equity.

Thamesport Chairman Geoffrey Parker described the sale as "the best possible news for existing and potential customers."

"We now have an owner who can provide the resources and commitment to meet demand and secure Thamesport's long-term future as a major U.K. gateway," he continued.

Unaudited accounts for the first eight months of 1995 show an operating profit of some UK2.4 million on throughput of 117,750 units. If the projected 180,000 traffic figure is achieved for the full year, Maritime Transport Services should show a profit of around UK3.9 million.

Michael Langdon, chief executive of Rutland, will become chairman of Maritime Transport.

Rutland indicated Monday that a further UK15 million may be invested in Thamesport "over time" in order to raise annual container handling capacity to 400,000, the figure originally targeted when the port opened five years ago.