ACTDU ArcLight Clean Transition Corporation II

CUSIP No. 68347P 103

AMENDMENT NO. 1 TO SCHEDULE 13D

Explanatory Note

This Amendment No. 1 (“Amendment No. 1”) amends and supplements the Schedule 13D (the “Original Schedule 13D”) filed on August 1, 2022 (as amended, the “Schedule 13D”). Except as specifically amended by this Amendment No. 1, the Schedule 13D remains in full force and effect. Capitalized terms used but not otherwise defined herein shall have the respective meanings previously ascribed to them in the Schedule 13D.

Item 5. Interest in Securities of the Issuer

Item 5 of the Original Schedule 13D is hereby amended and restated as follows:

(a)-(b) The information contained on the cover pages to this Schedule 13D is incorporated herein by reference. As noted on the cover pages, the beneficial ownership reflected in Box 13 of each cover page is calculated based on (i) 28,981,579 Class A Shares outstanding as of November 16, 2022 as reported on Issuer’s Prospectus, and plus (ii) 144,399,037 Class A Shares to be issued upon conversion of all the Class B Units and Class D Shares outstanding as of November 16, 2022 as reported on the Prospectus.   In accordance with the SEC’s rules for calculating “beneficial ownership,” which requires the Reporting Persons to disregard the conversion or exercise of the Class D Shares or warrants to acquire Class A Shares (“Warrants”) not held by the Reporting Persons, the Reporting Persons would be deemed to beneficially own approximately 32.6% of the outstanding Class A Shares. This percentage is calculated with a numerator of 9,448,582 and a denominator of 28,981,579.  Notwithstanding the foregoing, because a Class B Unit and Class D Share are economically equivalent to a Class A Share and further, the Class D Shares vote together with the Class A Shares, the reported 5.5% reflects the Reporting Person’s actual economic and voting interest in the Issuer.

The Reported Securities are held directly by the Sponsor. Daniel R. Revers has voting power and investment discretion with respect to the securities held by the Sponsor, and thus may be deemed to have beneficial ownership of the Reported Securities. The filing of this statement shall not be construed as an admission by either Reporting Person that such person is, for the purposes of sections 13(d) or 13(g) of the Exchange Act, the beneficial owner of any securities covered by this statement.

The Reported Securities include 763,907 Class A Shares that are subject to forfeiture (the “Sponsor Earn-Out”) pursuant to that certain Sponsor Letter Agreement, by and among the Sponsor, OPAL Fuels and certain parties thereto, dated as of December 2, 2021 (as amended from time to time, the “Sponsor Letter Agreement”). Pursuant to the Sponsor Letter Agreement, up to 10% of the Class A Shares beneficially owned by the Reporting Person as of July 21, 2022 will be subject to forfeiture if, during the 60 months following July 21, 2022, the following vesting conditions are not satisfied:

As used with respect to the Sponsor Earn-Out, “Sale” means (A) (1) a direct or indirect sale, lease, exchange or other transfer (regardless of the form of the transaction) in one transaction or a series of related transactions of a majority of the Issuer’s assets, as determined on a consolidated basis, to a third party or third parties acting as a “group” (as defined in Section 13(d)(3) of the Exchange Act) or (2) any transaction or series of transactions that results, directly or indirectly, in the shareholders of the Issuer as of immediately prior to such transactions holding, in the aggregate, less than 50% of the voting equity securities of the Issuer (or any successor of the Issuer) immediately after the consummation thereof (excluding any Sponsor Earnout Shares), in the case of each of clause (1) or (2), whether by amalgamation, merger, consolidation, arrangement, tender offer, recapitalization, purchase, issuance, sale or transfer of equity securities or assets or otherwise.

(c) Within the past sixty days, the Reporting Persons have engaged in the following transactions with respect to the Issuer’s securities: (i) on December 15, 2022, the Reporting Persons sold an aggregate of 2,000,000 Class A Shares in a block sale, for an aggregate sales price of $13,899,879 net of commissions and other execution-related costs and (ii) on December 22, 2022, the Reporting Persons exchanged 7,238,025 Warrants beneficially held by the Sponsor for 1,809,506 Class A Shares pursuant to the Issuer’s previously announced exchange offer. Except as set forth in this Section 5(c), the Reporting Persons have not effected any transaction in Class A Shares during the past sixty days.

(d) Not applicable.

(e) Not applicable.

SIGNATURES

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

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