Swampscott (Mass.) Contributory Retirement System, with $20 million to $30 million in assets, hired Segal Advisers as its first investment consultant. Segals first task will be to analyze the funds current investment portfolio, including reviewing the performance of the funds managers, said Kevin Leonard, the Segal Advisers consultant who is advising the fund. Segal will then conduct an asset allocation study. Ann McAllister, retirement administrator, did not return calls seeking comment.