X0306 4 2017-08-25 0000742126 US ECOLOGY, INC. ECOL 0001617541 Dorton Katina 251 E. FRONT ST. SUITE 400 BOISE ID 83702 1 Common Stock 2017-08-25 4 S 0 600 47.145 D 3970 D Common Stock 2017-08-25 4 P 0 600 47.155 A 3970 D Common Stock 1930 I Retirement Account Shares were purchased by the reporting person's retirement account. /s/ Katina Dorton 2017-08-25