X0202 4 2004-10-18 0000043704 GREEN MOUNTAIN POWER CORP GMP 0001247234 POWELL MARY G 163 ACORN LANE COLCHESTER VT 05446 0 1 0 0 Chief Operating Officer Common Stock 2004-10-18 4 M 0 3000 7.9 A 10900 D Common Stock 2004-10-18 4 S 0 800 25.4 D 10100 D Common Stock 2004-10-18 4 S 0 100 25.42 D 10000 D Common Stock 2004-10-18 4 S 0 500 25.45 D 9500 D Common Stock 2004-10-18 4 S 0 500 25.5 D 9000 D Common Stock 2004-10-18 4 S 0 200 25.54 D 8800 D Common Stock 2004-10-18 4 S 0 600 25.6 D 8200 D Common Stock 2004-10-18 4 S 0 200 25.69 D 8000 D Common Stock 2004-10-18 4 S 0 100 25.74 D 7900 D Common Stock 2372.7313 I By 401(k) Plan Stock Options (Right to buy) 7.9 2004-10-18 4 M 0 3000 0 D 2010-08-22 Common Stock 3000 12800 D The exercise of stock options and the sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 18, 2004. Includes 19.8656 shares acquired between July 16, 2004 and October 18, 2004 under the GMP 401(k) plan. The information in this report is based on a plan statement as of October 18, 2004. The option is currently exercisable for 12,800 shares. Donald J. Rendall, Jr., Attorney-In-Fact 2004-10-19