Exhibit 99.1 ------------ CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 I, Terry J. Logan, the Chief Executive Officer of N-Viro International Corporation, certify that (i) the Form 10-K fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and (ii) the information contained in the Form 10-K fairly presents, in all material respects, the financial condition and results of operations of N-Viro International Corporation. /s/ Terry J. Logan - --------------------- Terry J. Logan, Chief Executive Officer May 12, 2003 CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 I, James K. McHugh, the Chief Financial Officer of N-Viro International Corporation, certify that (i) the Form 10-K fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and (ii) the information contained in the Form 10-K fairly presents, in all material respects, the financial condition and results of operations of N-Viro International Corporation. /s/ James K. McHugh - ---------------------- James K. McHugh, Chief Financial Officer May 12, 2003