EXHIBIT 16 [LOGO OF PRICEWATERHOUSECOOPERS] PricewaterhouseCoopers LLP 600 Grant St. 52nd Floor Pittsburgh PA 15219 Telephone (412) 355 8000 Facsimile (412) 355 8089 Direct phone 412-355-6163 Direct fax 412-355-7564 Securities and Exchange Commission 450 Fifth Street, N.W. Washington D.C. 20549 May 15, 2000 Commissions We have read the statements made by Calgon Carbon Corporation (copy attached), which we understand will be filed with the Commission, pursuant to Item 4 of Form 8-K, as part of the Company's Form 8-K/A report dated April 7, 2000. We agree with the statements concerning our Firm in such Form 8-K/A. Very truly yours, /s/ PricewaterhouseCoopers LLP PricewaterhouseCoopers LLP