Ambient Noise Levels and Rule 012
The AUC published decision 22736-D01-2020 on January 27. (Lanfine Wind Power Project). In this decision, the AUC shines a light on the applicable ambient sound level (ASL) to be used in determining the permissible sound level (PSL). Which third party energy-related facilities are to be included in the NIA is also discussed.
For the ASL, the Commission considers that there are no substantive differences in this respect between the August 2019 version of Rule 12 and the previous version, as it did in decision 24401-D01-2019 as well. On behalf of the interveners, dBA Noise Consultants conducted ambient sound level measurements in the project area for 24 hours. The Commission is not satisfied that a duration of 24 hours is sufficient to capture representative ambient sound levels. Based on the presence of Oil & Gas facilities and agriculture the commission decided that the project area is not pristine or otherwise contains features that distinguishes it materially from other parts of rural Alberta. Therefore, the assumed ASL applies.
The Alberta Energy Regulator (AER) maintains several databases that contain information about the status of Oil & Gas facilities in an area. These databases do not contain direct acoustical information, or list the presence of equipment. Rather, the acoustical relevance and footprint of facilities has to be determined from other indicators, such as the description or the status. The Commission ruled that only wells that have status “pumping” need to be included in an NIA.
In Bulletin 2020-04, published on February 6, the Commission clarifies “pristine area”. Instead of the definition included in section 2.6(2) in Rule 12, the definition as included in Appendix 1 to Rule 012 applies. In that appendix a pristine area is defined as a natural area that might have a dwelling but no industrial presence, including energy, agricultural, forestry, manufacturing, recreational or other industries that affect the noise environment.
Section 2.6(2) will now read as follows: “The average nighttime ambient sound level in rural Alberta is approximately 35 dBA. Rule 012 does not require the use of a specific ambient sound level in a noise impact assessment. Applicants must assess the ambient sound level as part of a noise impact assessment, particularly in areas where there is non-energy industrial activity that would impact the ambient sound levels or where pristine (as defined in Appendix 1) surroundings prevail.”
In our opinion, section 2.6 (2) still requires an assessment about the validity of the assumed ASL having defined non-energy industries as agricultural, forestry, manufacturing, recreational or other industries that might affect the soundscape. For instance, agricultural industry is present everywhere in rural Alberta. If there is an indication that the ambient sound level may differ from the assumed ambient sound level, a more thorough assessment of the ambient sound level may be required to satisfy either stakeholders or the commission.