§ 80.165 Attest engagements.
(a) General provisions. (1) The following parties must arrange for annual attestation engagement using agreed-upon procedures:
(i) Biogas producers.
(ii) RNG producers.
(iii) RNG importers.
(iv) Biogas closed distribution system RIN generators.
(v) RNG RIN separators.
(vi) Renewable fuel producers that use RNG as a feedstock.
(2) The auditor performing attestation engagements required under this subpart must meet the requirements in 40 CFR 1090.1800(b).
(3) The auditor must perform attestation engagements separately for each biogas production facility, RNG production facility, and renewable fuel production facility, as applicable.
(4) Except as otherwise specified in this section, attest auditors may use the representative sampling procedures specified in 40 CFR 1090.1805.
(5) Except as otherwise specified in this section, attest auditors must prepare and submit the annual attestation engagement following the procedures specified in 40 CFR 1090.1800(d).
(b) General procedures for biogas producers. An attest auditor must conduct annual attestation audits for biogas producers using the following procedures:
(1) Registration and EPA reports. The auditor must review registration and EPA reports as follows:
(i) Obtain copies of all the following:
(A) The biogas producer's registration information submitted under §§ 80.135 and 80.1450.
(B) All reports submitted under §§ 80.140 and 80.1451.
(ii) For each biogas production facility, confirm that the facility's registration is accurate based on the activities reported during the compliance period and confirm any related updates were completed prior to conducting regulated activities at the facility and report as a finding any exceptions.
(iii)
(A) Report the date of the last engineering review conducted under §§ 80.135(b)(3) and 80.1450(b), as applicable.
(B) Report as a finding if the last engineering review is outside of the schedule specified in § 80.1450(d)(3)(ii).
(iv) Confirm that the biogas producer submitted all reports required under §§ 80.140 and 80.1451 for activities performed during the compliance period and report as a finding any exceptions.
(2) Measurement method review. The auditor must review measurement methods for each meter as follows:
(i) Obtain records related to measurement under § 80.145(a)(1)(vi).
(ii)
(A) Identify and report the name of the method(s) used for measuring the volume of biogas, in Btu HHV and scf.