DESCRIPTION OF BUSINESS	12 Months Ended
Dec. 31, 2021
GENERAL
DESCRIPTION OF BUSINESS	NOTE 1. DESCRIPTION OF BUSINESS US Ecology Holdings, Inc., the predecessor to the Company (“Predecessor US Ecology”), was incorporated as a Delaware corporation in March 1987 as American Ecology Corporation. On February 22, 2010, Predecessor US Ecology changed its name from American Ecology Corporation to US Ecology, Inc. On November 1, 2019, in connection with the Company’s acquisition of NRC Group Holdings Corp. (“NRC”), a new parent entity of US Ecology completed a merger transaction with Predecessor US Ecology and became the successor to Predecessor US Ecology and changed its name to “US Ecology, Inc.” In connection with the closing of the NRC Merger (as defined below), Predecessor US Ecology changed its name to “US Ecology Holdings, Inc.” US Ecology, Inc., through its subsidiaries, is a leading North American provider of environmental services to commercial and government entities. The Company addresses the complex waste management needs of its customers, offering treatment, disposal and recycling of hazardous and radioactive waste, as well as a wide range of complementary field services. US Ecology, Inc. and its predecessors have been protecting the environment since 1952, with operations primarily in the United States, Canada, the Europe, Middle East, and Africa (“EMEA”) region and Mexico. Throughout these consolidated financial statements words such as “we,” “us,” “our,” “US Ecology” and the “Company” refer to US Ecology, Inc. and its subsidiaries. On November 1, 2019, pursuant to and subject to the conditions set forth in the Agreement and Plan of Merger (the “NRC Merger Agreement”) by and among the Company, NRC, Predecessor US Ecology, Rooster Merger Sub, Inc. (“NRC Merger Sub”), and ECOL Merger Sub, Inc. (“ECOL Merger Sub”), ECOL Merger Sub merged with and into Predecessor US Ecology, with Predecessor US Ecology continuing as the surviving company and as a wholly-owned subsidiary of the Company. Substantially concurrently therewith, NRC Merger Sub merged with and into NRC, with NRC continuing as the surviving company and as a wholly-owned subsidiary of the Company. Following the completion of the mergers (collectively, the “NRC Merger”), the Company contributed all of the issued and outstanding equity interests of NRC to Predecessor US Ecology so that, after such contribution, NRC became a wholly-owned subsidiary of Predecessor US Ecology. Effective as of November 1, 2019, the Company changed its name from “US Ecology Parent, Inc.” to “US Ecology, Inc.,” the Company’s common stock and warrants began trading on Nasdaq under the symbol “ECOL” and “ECOLW,” respectively. The Company identified itself as the successor issuer to Predecessor US Ecology pursuant to Rule 12g-3(c) under the Securities Exchange Act of 1934, as amended. Effective in the fourth quarter of 2020, we made changes to the manner in which we manage our business, make operating decisions and assess our performance. The energy waste business that was acquired through the NRC Merger now comprises our Energy Waste segment. Prior to this change, the energy waste business was included in the Waste Solutions segment (formerly “Environmental Services”). Throughout this Annual Report on Form 10-K, all periods presented have been recast to reflect these changes. Under our new structure our operations are managed in three reportable segments reflecting our internal management reporting structure and nature of services offered as follows: Waste Solutions (formerly “Environmental Services”)—This segment provides safe and compliant specialty waste management services including treatment, disposal, beneficial re-use, and recycling of hazardous, non-hazardous, and other specialty waste at Company-owned treatment, storage, and disposal facilities, excluding the services within our Energy Waste segment. Field Services (formerly “Field & Industrial Services”)—This segment provides safe and compliant logistics and response solutions focusing on “in-field’ service offerings through our network of 10-day transfer facilities. Our logistics solutions include specialty waste packaging, collection, transportation, and total waste management. Our response solutions include land and marine based emergency response, OSRO standby compliance, remediation, and industrial services. The Field Services segment completes our vertically integrated model and serves to increase waste volumes into our Waste Solutions segment. Energy Waste—This segment provides safe and compliant energy waste management and critical support services to up-stream oil and gas customers in the Permian and Eagle Ford basins primarily operating in Texas. Services include spill containment and site remediation, equipment cleaning and maintenance services, specialty equipment rental, including tanks, pumps and containment, safety monitoring and management and transportation and disposal. This segment includes all of the energy waste business of the legacy NRC operations and none of the legacy US Ecology operations. Effective in the first quarter of 2021, we changed our management structure resulting in the reclassification of certain overhead expenses from our Waste Solutions, Field Services and Energy Waste reportable segments to Corporate. As a result, certain regional overhead costs historically presented within our reportable segments as Direct operating costs were further reclassified to Corporate as Selling, general and administrative expenses to conform to the current period’s presentation. Throughout this Annual Report on Form 10-K, all periods presented have been recast to reflect these changes.

DESCRIPTION OF BUSINESS

12 Months Ended

Dec. 31, 2021

NOTE 1. DESCRIPTION OF BUSINESS

US Ecology Holdings, Inc., the predecessor to the Company (“Predecessor US Ecology”), was incorporated as a Delaware corporation in March 1987 as American Ecology Corporation. On February 22, 2010, Predecessor US Ecology changed its name from American Ecology Corporation to US Ecology, Inc. On November 1, 2019, in connection with the Company’s acquisition of NRC Group Holdings Corp. (“NRC”), a new parent entity of US Ecology completed a merger transaction with Predecessor US Ecology and became the successor to Predecessor US Ecology and changed its name to “US Ecology, Inc.” In connection with the closing of the NRC Merger (as defined below), Predecessor US Ecology changed its name to “US Ecology Holdings, Inc.” US Ecology, Inc., through its subsidiaries, is a leading North American provider of environmental services to commercial and government entities. The Company addresses the complex waste management needs of its customers, offering treatment, disposal and recycling of hazardous and radioactive waste, as well as a wide range of complementary field services. US Ecology, Inc. and its predecessors have been protecting the environment since 1952, with operations primarily in the United States, Canada, the Europe, Middle East, and Africa (“EMEA”) region and Mexico. Throughout these consolidated financial statements words such as “we,” “us,” “our,” “US Ecology” and the “Company” refer to US Ecology, Inc. and its subsidiaries.

On November 1, 2019, pursuant to and subject to the conditions set forth in the Agreement and Plan of Merger (the “NRC Merger Agreement”) by and among the Company, NRC, Predecessor US Ecology, Rooster Merger Sub, Inc. (“NRC Merger Sub”), and ECOL Merger Sub, Inc. (“ECOL Merger Sub”), ECOL Merger Sub merged with and into Predecessor US Ecology, with Predecessor US Ecology continuing as the surviving company and as a wholly-owned subsidiary of the Company. Substantially concurrently therewith, NRC Merger Sub merged with and into NRC, with NRC continuing as the surviving company and as a wholly-owned subsidiary of the Company. Following the completion of the mergers (collectively, the “NRC Merger”), the Company contributed all of the issued and outstanding equity interests of NRC to Predecessor US Ecology so that, after such contribution, NRC became a wholly-owned subsidiary of Predecessor US Ecology.

Effective as of November 1, 2019, the Company changed its name from “US Ecology Parent, Inc.” to “US Ecology, Inc.,” the Company’s common stock and warrants began trading on Nasdaq under the symbol “ECOL” and “ECOLW,” respectively. The Company identified itself as the successor issuer to Predecessor US Ecology pursuant to Rule 12g-3(c) under the Securities Exchange Act of 1934, as amended.

Effective in the fourth quarter of 2020, we made changes to the manner in which we manage our business, make operating decisions and assess our performance. The energy waste business that was acquired through the NRC Merger now comprises our Energy Waste segment. Prior to this change, the energy waste business was included in the Waste Solutions segment (formerly “Environmental Services”). Throughout this Annual Report on Form 10-K, all periods presented have been recast to reflect these changes. Under our new structure our operations are managed in three reportable segments reflecting our internal management reporting structure and nature of services offered as follows:

Waste Solutions (formerly “Environmental Services”)—This segment provides safe and compliant specialty waste management services including treatment, disposal, beneficial re-use, and recycling of hazardous, non-hazardous, and other specialty waste at Company-owned treatment, storage, and disposal facilities, excluding the services within our Energy Waste segment.

Field Services (formerly “Field & Industrial Services”)—This segment provides safe and compliant logistics and response solutions focusing on “in-field’ service offerings through our network of 10-day transfer facilities. Our logistics solutions include specialty waste packaging, collection, transportation, and total waste management. Our response solutions include land and marine based emergency response, OSRO standby compliance, remediation, and industrial services. The Field Services segment completes our vertically integrated model and serves to increase waste volumes into our Waste Solutions segment.

Energy Waste—This segment provides safe and compliant energy waste management and critical support services to up-stream oil and gas customers in the Permian and Eagle Ford basins primarily operating in Texas. Services include spill containment and site remediation, equipment cleaning and maintenance services, specialty equipment rental, including tanks, pumps and containment, safety monitoring and management and transportation and disposal. This segment includes all of the energy waste business of the legacy NRC operations and none of the legacy US Ecology operations.

Effective in the first quarter of 2021, we changed our management structure resulting in the reclassification of certain overhead expenses from our Waste Solutions, Field Services and Energy Waste reportable segments to Corporate. As a result, certain regional overhead costs historically presented within our reportable segments as Direct operating costs were further reclassified to Corporate as Selling, general and administrative expenses to conform to the current period’s presentation. Throughout this Annual Report on Form 10-K, all periods presented have been recast to reflect these changes.