associated forecast 2021 Facility Carbon Charge cost of $1.47 million as detailed at Exhibit B, Tab 2, Schedule 5.3

3.2. OBPS VOLUMES

• 7. The OBPS Volume forecast for 2021 for the Union rate zones is 143,679 103m3 as detailed at Exhibit B, Tab 2, Schedule 2.4 The subsequent forecast 2021 OBPS obligation of 96,961 tCO2e results in a Facility Carbon Charge cost of $3.88 million as detailed at Exhibit B, Tab 2, Schedules 4 and 5. Of the $3.88 million, $3.39 million is attributable to Enbridge Gas’s regulated operations in the Union rate zones.

• 8. The OBPS Volume forecast is derived by combining forecasts for regulated utility and unregulated non-utility compression activity into an overall physical activity forecast. Enbridge Gas has excluded unregulated non-utility compression volumes and associated costs in deriving the Facility Carbon Charge cost to be recovered in regulated rates. The OBPS Volume forecast for the Union rate zones includes transmission compression, storage compression and dehydration fuel.5

• 9. Enbridge Gas’s detailed calculations of the 2021 forecast compressor emissions, facility emissions limit, OBPS compliance obligation and compressor fuel use cost for the Union rate zones can be found at Exhibit B, Tab 2, Schedule 3-5.

3 Included in the Company Use Volume forecast for 2021 is 18 103m3 for distribution buildings associated with non-utility unregulated storage activity. Enbridge Gas has not accounted for this amount separately as it is immaterial, resulting in costs of less than $1,500.

• 4 This includes both utility (regulated) and non-utility (unregulated) volumes.

• 5 The transmission and storage compression forecast is derived by combining forecasts for in-franchise and ex-franchise transmission and storage activity into an overall physical activity forecast. For dehydration fuel, average historical utilization is used to estimate the monthly forecasted usage.