1 EXHIBIT 99.1 [GRANT THORNTON LETTERHEAD] April 23, 1999 Securities and Exchange Commission Washington, D.C. 20549 Re: SeQuester Holding, Incorporated File NO. 33-06827LA Dear Sir or Madam: We have read item 4 of the Form 8-K of Client Company dated April 23, 1999, and agree with the statements contained in Section A of that Item. We do not have sufficient knowledge to comment on the statements in Section B. Very truly yours, /s/ GRANT THORNTON LLP