Certificate of RegistrationThis certifies that the Environmental Management System of

US Ecology Romulus36345 Van Born Road

Romulus, Michigan, 48174, United States

has been assessed by NSF-ISR and found to be in conformance to the following standard(s):

ISO 14001:2015Scope of Registration:

Providing de-icing fluid collection services and recycling, NMP recycling, laboratory analytical services, and on-site groundwater treatment.

Carl Blazik,Director, Technical Operations & Business Units,NSF-ISR, Ltd.

Page 1 of 3

Certificate Number: 6S202-EM1Certificate Issue Date: 01-JUN-2018Registration Date: 08-MAY-2018Expiration Date *: 07-MAY-2021

This Annex is only Valid in connection with the above-mentioned certificate issued by NSF-ISR

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ANNEX PAGE FOR CERTIFICATE REGISTRATION NUMBER 6S202-EM1

CERTIFICATE ISSUE DATE: 01-JUN-2018CERTIFICATE EXPIRATION DATE: 07-MAY-2021

US Ecology Romulus36345 Van Born Road

Romulus, Michigan, 48174, United States

Remote Location: US Ecology Tampa- 6S195

7202 East 8th Ave.Tampa, Florida, 33619, United States

Scope:Commercial hazardous waste storage and treatment facility engaged in the business of treatment and recovery technologies for the management of chemicalwastes. Fleet of vehicles licensed and equipped to transport a wide variety of Hazardous Materials to support customers needs.

Remote Location: US Ecology Mt. Airy- 6S197540 W. Independence Blvd.

Mt. Airy, North Carolina, 27030, United States

Scope:Provider of recycling of waste organic solvents.

Remote Location: US Ecology Detroit (South)- 6S214

1923 Fredrick St.Detroit, Michigan, 48211, United States

Scope:Provider of hazardous and non-hazardous waste treatment stabilization, LTL trucking services, drum transfer activities, and universal waste and other recycling programs.

Remote Location: US Ecology Michigan- 6S216

Wayne Disposal, Inc.andMichigan Disposal Waste Treatment Plant

49350 N. I-94 Service DriveBelleville, Michigan, 48111, United States

Scope:Treatment and disposal of hazardous and non-hazardous waste.

Remote Location: US Ecology Minneapolis- C0051697

2520 Cargo RoadMinneapolis, Minnesota, 55450, United States

Scope:Recycling of airport de-icing fluid.

This Annex is only Valid in connection with the above-mentioned certificate issued by NSF-ISR

Page 3 of 3

ANNEX PAGE FOR CERTIFICATE REGISTRATION NUMBER 6S202-EM1

CERTIFICATE ISSUE DATE: 01-JUN-2018CERTIFICATE EXPIRATION DATE: 07-MAY-2021

US Ecology Romulus36345 Van Born Road

Romulus, Michigan, 48174, United States

Remote Location: US Ecology York- C0066982

730 Vogelsong RoadYork, Pennsylvania, 17404, United States

Scope:Provider of hazardous and non-hazardous waste management services including recycling, treatment, storage, disposal, and transportation

Remote Location: US Ecology Chicago- C0066997

16435 Center AvenueHarvey, Illinois, 60426, United States

Scope:Commercial hazardous waste storage and treatment facility engaged in the business of applying treatment and recovery technologies tor the management of industrial wastes. Fleet of vehicles licensed and equipped to transport a wide variety of Hazardous Materials to support customers needs.

Remote Location: US Ecology Canton- C0066998

2050 Central AvenueCanton, 44707,

Scope:RCRA Part B permitted commercial hazardous waste storage,treatment, and recycling facility with Clean Water Act regulatedCentralized Waste Treatment (WWT) capabilities as well as a fleet ofvehicles licensed and equipped to transport a wide variety ofHazardous Materials.

Remote Location: US Ecology Tulsa- C00669992700 South 25th West Avenue

Tulsa, Oklahoma, 74107, United States

Scope:Management of hazardous and non-hazardous, liquids, solids and debris and provide safe and effective hazardous waste management solutions.

Remote Location: US Ecology Sulligent- C0180143

51328 AL Hwy 17Sulligent, Alabama, 35586, United States

Scope:Provider of hazardous waste transportation and transfer facility.