Exhibit 99.1

JOINT FILING AGREEMENT

The undersigned hereby agree that they are filing this statement on Schedule 13D jointly pursuant to Rule 13d-1(k)(1). Each of them is responsible for the timely filing of such Schedule 13D and any amendments thereto, and for the completeness and accuracy of the information concerning such person contained therein; but none of them is responsible for the completeness or accuracy of the information concerning the other persons making the filing, unless such person knows or has reason to believe that such information is inaccurate.

In accordance with Rule 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with each other on behalf of each of them of such a statement on Schedule 13D with respect to the Class A Common Stock, par value $0.0001 per share, of Archaea Energy Inc., a Delaware corporation, beneficially owned by each of them. This Joint Filing Agreement shall be included as an exhibit to such Schedule 13D.

IN WITNESS WHEREOF, the undersigned hereby execute this Joint Filing Agreement as of the 15th day of December, 2021.

Date: December 15, 2021

Aria Renewable Energy Systems LLC

/s/ Noah Ehrenpreis                              

By:  Noah Ehrenpreis

Its:  Vice President

United States Power Fund III, L.P.

By: EIF US Power III, LLC, its general partner

By: Ares EIF Management, LLC, its managing member

/s/ Noah Ehrenpreis                               

By:  Noah Ehrenpreis

Its:  Vice President

EIF US Power III, LLC

By: Ares EIF Management, LLC, its managing member

/s/ Noah Ehrenpreis                              

By:  Noah Ehrenpreis

Its:  Vice President

EIF United States Power Fund IV, L.P.

By: EIF US Power IV, LLC, its general partner

By: Ares EIF Management, LLC, its managing member

/s/ Noah Ehrenpreis                              

By:  Noah Ehrenpreis

Its:  Vice President

EIF US Power IV, LLC

By: Ares EIF Management, LLC, its managing member

/s/ Noah Ehrenpreis                               

By:  Noah Ehrenpreis

Its:  Vice President

Ares EIF Management LLC

/s/ Noah Ehrenpreis                                

By:  Noah Ehrenpreis

Its:  Vice President

Ares Management LLC

/s/ Naseem Sagati Aghili                        

By:  Naseem Sagati Aghili

Its:  Authorized Signatory

Ares Management Holdings L.P.

By: Ares Holdco LLC, its general partner

/s/ Naseem Sagati Aghili                      

By:  Naseem Sagati Aghili

Its:  Authorized Signatory

Ares Holdco LLC

/s/ Naseem Sagati Aghili                       

By:  Naseem Sagati Aghili

Its:  Authorized Signatory

Ares Management Corporation

/s/ Naseem Sagati Aghili                       

By:  Naseem Sagati Aghili

Its:  Authorized Signatory

Ares Voting LLC

By: Ares Partners Holdco LLC, its sole member

/s/ Naseem Sagati Aghili                        

By:  Naseem Sagati Aghili

Its:  Authorized Signatory

Ares Management GP LLC

/s/ Naseem Sagati Aghili                         

By:  Naseem Sagati Aghili

Its:  Authorized Signatory

Ares Partners Holdco LLC

/s/ Naseem Sagati Aghili                           

By:  Naseem Sagati Aghili

Its:  Authorized Signatory