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US Ecology, Inc. – ‘10-K’ for 12/31/21 – ‘XML’

On:  Monday, 2/28/22, at 2:24pm ET   ·   For:  12/31/21   ·   Accession #:  1558370-22-2321   ·   File #:  1-39120

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  As Of               Filer                 Filing    For·On·As Docs:Size             Issuer                      Filing Agent

 2/28/22  US Ecology, Inc.                  10-K       12/31/21  133:18M                                    Toppan Merrill Bridge/FA

Annual Report   —   Form 10-K

Filing Table of Contents

Document/Exhibit                   Description                      Pages   Size 

 1: 10-K        Annual Report                                       HTML   2.39M 
 2: EX-4.2      Instrument Defining the Rights of Security Holders  HTML     98K 
 3: EX-21.1     Subsidiaries List                                   HTML     55K 
 4: EX-23.1     Consent of Expert or Counsel                        HTML     33K 
 5: EX-31.1     Certification -- §302 - SOA'02                      HTML     40K 
 6: EX-31.2     Certification -- §302 - SOA'02                      HTML     40K 
 7: EX-32.1     Certification -- §906 - SOA'02                      HTML     34K 
 8: EX-32.2     Certification -- §906 - SOA'02                      HTML     35K 
14: R1          Document and Entity Information                     HTML    106K 
15: R2          Consolidated Balance Sheets                         HTML    154K 
16: R3          Consolidated Balance Sheets (Parenthetical)         HTML     44K 
17: R4          Consolidated Statements of Operations               HTML    113K 
18: R5          Consolidated Statements of Comprehensive Income     HTML     56K 
                (Loss)                                                           
19: R6          Consolidated Statements of Comprehensive Income     HTML     36K 
                (Loss) (Parenthetical)                                           
20: R7          Consolidated Statements of Cash Flows               HTML    167K 
21: R8          Consolidated Statements of Cash Flows -             HTML     44K 
                (Restricted cash and investments)                                
22: R9          Consolidated Statements of Stockholders' Equity     HTML    115K 
23: R10         Consolidated Statements of Stockholders' Equity     HTML     36K 
                (Parenthetical)                                                  
24: R11         Description of Business                             HTML     42K 
25: R12         Summary of Significant Accounting Policies          HTML     73K 
26: R13         Use of Estimates                                    HTML     48K 
27: R14         Revenues                                            HTML    245K 
28: R15         Business Combinations                               HTML     98K 
29: R16         Accumulated Other Comprehensive Income (Loss)       HTML     71K 
30: R17         Disclosure of Supplemental Cash Flow Information    HTML     62K 
31: R18         Fair Value Measurements                             HTML    130K 
32: R19         Concentrations and Credit Risk                      HTML     38K 
33: R20         Receivables                                         HTML     78K 
34: R21         Property and Equipment                              HTML     53K 
35: R22         Leases                                              HTML    143K 
36: R23         Goodwill and Intangible Assets                      HTML    202K 
37: R24         Employee Benefit Plans                              HTML     61K 
38: R25         Closure and Post-Closure Obligations                HTML     72K 
39: R26         Debt                                                HTML     90K 
40: R27         Income Taxes                                        HTML    176K 
41: R28         Commitments and Contingencies                       HTML     45K 
42: R29         Equity                                              HTML    175K 
43: R30         Earnings (Loss) Per Share                           HTML     82K 
44: R31         Segment Reporting                                   HTML    198K 
45: R32         Subsequent Events                                   HTML     40K 
46: R33         Summary of Significant Accounting Policies          HTML    124K 
                (Policies)                                                       
47: R34         Summary of Significant Accounting Policies          HTML     44K 
                (Tables)                                                         
48: R35         Revenues (Tables)                                   HTML    238K 
49: R36         Business Combinations (Tables)                      HTML    176K 
50: R37         Accumulated Other Comprehensive Income (Loss)       HTML     70K 
                (Tables)                                                         
51: R38         Disclosure of Supplemental Cash Flow Information    HTML     61K 
                (Tables)                                                         
52: R39         Fair Value Measurements (Tables)                    HTML    127K 
53: R40         Receivables (Tables)                                HTML     79K 
54: R41         Property and Equipment (Tables)                     HTML     51K 
55: R42         Leases (Tables)                                     HTML    147K 
56: R43         Goodwill and Intangible Assets (Tables)             HTML    186K 
57: R44         Employee Benefit Plans (Tables)                     HTML     53K 
58: R45         Closure and Post-Closure Obligations (Tables)       HTML     68K 
59: R46         Debt (Tables)                                       HTML     77K 
60: R47         Income Taxes (Tables)                               HTML    177K 
61: R48         Equity (Tables)                                     HTML    169K 
62: R49         Earnings (L0Ss) Per Share (Tables)                  HTML     82K 
63: R50         Segment Reporting (Tables)                          HTML    188K 
64: R51         Description of Business (Details)                   HTML     35K 
65: R52         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Cash   HTML     41K 
                and Cash Equivalents (Details)                                   
66: R53         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -        HTML     36K 
                Restricted Cash and Investments (Details)                        
67: R54         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -        HTML     37K 
                Deferred Revenue (Details)                                       
68: R55         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -        HTML     54K 
                Property and Equipment (Details)                                 
69: R56         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -        HTML     35K 
                Disposal Cell Accounting (Details)                               
70: R57         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -        HTML     43K 
                Intangible Assets (Details)                                      
71: R58         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Debt   HTML     43K 
                Issuance Costs & Debt Discount (Details)                         
72: R59         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -        HTML     35K 
                Derivative Instruments (Details)                                 
73: R60         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES -        HTML     35K 
                Insurance (Details)                                              
74: R61         Revenues (Details)                                  HTML     85K 
75: R62         Revenues - Treatment and Disposal Revenue           HTML     51K 
                (Details)                                                        
76: R63         REVENUES - Geography (Details)                      HTML     65K 
77: R64         REVENUES - Practical Expedients (Details)           HTML     40K 
78: R65         BUSINESS COMBINATIONS - Merger consideration        HTML     89K 
                (Details)                                                        
79: R66         BUSINESS COMBINATIONS - Preliminary fair value      HTML    101K 
                estimates of assets acquired and liabilities                     
                assumed recognized (Details)                                     
80: R67         BUSINESS COMBINATIONS - Preliminary fair value of   HTML     58K 
                identifiable intangible assets (Details)                         
81: R68         BUSINESS COMBINATIONS - Pro forma information       HTML     49K 
                (Details)                                                        
82: R69         BUSINESS COMBINATIONS - Additional Information      HTML     75K 
                (Details)                                                        
83: R70         Accumulated Other Comprehensive Income (LOSS) -     HTML     57K 
                Changes in AOCI (Details)                                        
84: R71         Accumulated Other Comprehensive Income (LOSS)       HTML     49K 
                -Reclassifications Line Items (Details)                          
85: R72         Disclosure of Supplemental Cash Flow Information    HTML     53K 
                (Details)                                                        
86: R73         Fair Value Measurements (Details)                   HTML     89K 
87: R74         Fair Value Measurements - Changes in Level 3        HTML     45K 
                liabilities measured at fair value (Details)                     
88: R75         Concentrations and Credit Risk (Details)            HTML     44K 
89: R76         Receivables (Details)                               HTML     57K 
90: R77         Property and Equipment (Details)                    HTML     59K 
91: R78         Leases (Details)                                    HTML     49K 
92: R79         Leases - Leased assets and liabilities (Details)    HTML     57K 
93: R80         LEASES - Lease cost (Details)                       HTML     43K 
94: R81         LEASES - Supplemental Cash Flow information         HTML     45K 
                (Details)                                                        
95: R82         LEASES - Weighted-average remaining lease term and  HTML     43K 
                discount rate (Details)                                          
96: R83         LEASES - Maturity analysis of operating and         HTML     92K 
                finance lease liabilities (Details)                              
97: R84         GOODWILL AND INTANGIBLE ASSETS - Goodwill           HTML    106K 
                (Details)                                                        
98: R85         Goodwill and Intangible Assets (Details)            HTML     49K 
99: R86         Goodwill and Intangible Assets - Impairment         HTML     36K 
                (Details)                                                        
100: R87         GOODWILL AND INTANGIBLE ASSETS - Intangible Assets  HTML    108K  
                (Details)                                                        
101: R88         GOODWILL AND INTANGIBLE ASSETS - Future             HTML     50K  
                amortization expense (Details)                                   
102: R89         Employee Benefit Plans (Details)                    HTML     64K  
103: R90         Closure and Post-Closure Obligations (Details)      HTML     38K  
104: R91         Closure and Post-Closure Obligations - Fair Value   HTML     41K  
                Assumptions (Details)                                            
105: R92         CLOSURE AND POST-CLOSURE OBLIGATIONS - Rollforward  HTML     61K  
                (Details)                                                        
106: R93         Closure and Post-Closure Obligations - Changes      HTML     43K  
                (Details)                                                        
107: R94         DEBT - Schedule (Details)                           HTML     52K  
108: R95         DEBT - Future Maturities (Details)                  HTML     51K  
109: R96         DEBT - Paragraph (Details)                          HTML    118K  
110: R97         DEBT - Loan Interest Margin (Details)               HTML     98K  
111: R98         DEBT - Leverage Ratio (Details)                     HTML     37K  
112: R99         Income Taxes (Details)                              HTML    121K  
113: R100        Income Taxes - Deferred Tax Assets and Liabilities  HTML     83K  
                (Details)                                                        
114: R101        Income Taxes - Domestic and Foreign Components      HTML     56K  
                (Details)                                                        
115: R102        COMMITMENTS AND CONTINGENCIES - Litigation and      HTML     37K  
                Regulatory Proceedings (Details)                                 
116: R103        EQUITY - Equity Based Purchase Consideration        HTML     46K  
                (Details)                                                        
117: R104        EQUITY - Stock Repurchase Program (Details)         HTML     41K  
118: R105        EQUITY - Omnibus Incentive Plan (Details)           HTML     42K  
119: R106        EQUITY - PSUs, Restricted Stock and RSU (Details)   HTML    138K  
120: R107        EQUITY - Stock Options (Details)                    HTML     84K  
121: R108        EQUITY - Treasury Stock (Details)                   HTML     49K  
122: R109        EQUITY - Share-based Compensation Expense           HTML     64K  
                (Details)                                                        
123: R110        EQUITY - Warrants (Details)                         HTML     48K  
124: R111        Earnings (Loss) Per Share (Details)                 HTML     75K  
125: R112        SEGMENT REPORTING - Summarized Financial            HTML     71K  
                Information (Details)                                            
126: R113        SEGMENT REPORTING - Reconciliation of EBITDA        HTML     95K  
                (Details)                                                        
127: R114        SEGMENT REPORTING - Revenue and Long-lived Assets   HTML     44K  
                (Details)                                                        
128: R115        Subsequent Events (Details)                         HTML     46K  
131: XML         IDEA XML File -- Filing Summary                      XML    247K  
129: XML         XBRL Instance -- ecol-20211231x10k_htm               XML   5.08M  
130: EXCEL       IDEA Workbook of Financial Reports                  XLSX    192K  
10: EX-101.CAL  XBRL Calculations -- ecol-20211231_cal               XML    340K 
11: EX-101.DEF  XBRL Definitions -- ecol-20211231_def                XML   1.16M 
12: EX-101.LAB  XBRL Labels -- ecol-20211231_lab                     XML   2.30M 
13: EX-101.PRE  XBRL Presentations -- ecol-20211231_pre              XML   1.79M 
 9: EX-101.SCH  XBRL Schema -- ecol-20211231                         XSD    303K 
132: JSON        XBRL Instance as JSON Data -- MetaLinks              660±   979K  
133: ZIP         XBRL Zipped Folder -- 0001558370-22-002321-xbrl      Zip    601K  


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1 Subsequent Filing that References this Filing

  As Of               Filer                 Filing    For·On·As Docs:Size             Issuer                      Filing Agent

 4/15/22  US Ecology, Inc.                  10-K/A     12/31/21   13:1.3M                                   Toppan Merrill/FA


17 Previous Filings that this Filing References

  As Of               Filer                 Filing    For·On·As Docs:Size             Issuer                      Filing Agent

 2/10/22  US Ecology, Inc.                  8-K:1,7,9   2/08/22   13:932K                                   Toppan Merrill/FA
 7/01/21  US Ecology, Inc.                  8-K:1,7,9   6/29/21   13:1.8M                                   GlobalOne Filings Inc/FA
 6/01/21  US Ecology, Inc.                  8-K:5,8,9   5/25/21   12:276K                                   Toppan Merrill/FA
 5/03/21  US Ecology, Inc.                  10-Q        3/31/21   92:10M                                    Toppan Merrill Bridge/FA
 4/13/21  US Ecology, Inc.                  DEF 14A     5/25/21    1:3.2M                                   Toppan Merrill/FA
 3/01/21  US Ecology, Inc.                  10-K       12/31/20  137:20M                                    Toppan Merrill Bridge/FA
 6/29/20  US Ecology, Inc.                  8-K:1,9     6/26/20   12:1.8M                                   GlobalOne Filings Inc/FA
 1/07/20  US Ecology, Inc.                  S-8         1/07/20    7:609K                                   Toppan Merrill/FA
11/01/19  US Ecology, Inc.                  S-8        11/01/19    9:516K                                   Toppan Merrill/FA
11/01/19  US Ecology, Inc.                  8-K:1,2,3,511/01/19    9:941K                                   Toppan Merrill/FA
 8/09/19  US Ecology Holdings, Inc.         8-K:1,9     8/06/19   11:1.8M                                   GlobalOne Filings Inc/FA
 6/24/19  US Ecology Holdings, Inc.         8-K:1,7,9   6/23/19    6:1.5M                                   Toppan Merrill/FA
 5/06/19  US Ecology Holdings, Inc.         10-Q        3/31/19   95:10M                                    Toppan Merrill Bridge/FA
 4/20/17  US Ecology Holdings, Inc.         8-K:1,2,9   4/18/17    2:1.1M                                   GlobalOne Filings Inc/FA
11/12/14  US Ecology Holdings, Inc.         8-K:1,9    11/07/14    2:105K                                   Publicease Inc./FA
 8/07/07  US Ecology Holdings, Inc.         10-Q        6/30/07    5:306K                                   Bowne - BPC/FA
 7/29/05  US Ecology Holdings, Inc.         8-K:1       7/27/05    3:48K                                    Summit Fin’l Dis… LLC/FA
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