1 EX-23.1 CONSENT OF ARTHUR ANDERSEN LLP ARTHUR ANDERSEN LLP EXHIBIT 23.1 CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS As independent public accountants, we hereby consent to the incorporation of our report included in this Form 8-K, into the Company's previously filed Registration Statements on Form S-8 (File Nos. 333-01616, 333-04073, 333-46705, 333-57233, 333-65413, 333-79425 and 333-79429). Arthur Andersen LLP Denver, Colorado, September 15, 2000. 29