X0306 4 2020-03-13 0 0001136294 Williams Industrial Services Group Inc. WLMS 0001285260 MILLS ROBERT B C/O WILLIAMS INDUSTRIAL SRVS GRP INC. 100 CRESCENT CENTRE PKWY STE 1240 TUCKER GA 30084 1 0 0 0 Common Stock, $0.01 par value per share 2020-03-13 4 A 0 73171 0 A 290416 D Consists of restricted shares granted under the 2015 Equity Incentive Plan, as amended and restated, all of which will vest on March 13, 2021. The vesting of the grant disclosed herein is subject to continued service as a director through the vesting and accelerated vesting in the event of certain terminations. Any shares that do not vest will be forfeited. /s/ Charles E. Wheelock for Robert B. Mills by Power of Attorney 2020-03-17