2016-04-19 P&E Committee - Item 1, Attachment 2 - Air Quality Assessment Report

3.2.3      Tank Breathing
Tank breathing or venting is a daily occurrence that is a result of fuel evaporation and barometric
pressure within the bulk tanks at the service station. These emissions are directed to atmosphere
through a small venting stack on the site. Emissions are variable depending on a number of
conditions such as fuel types, temperatures and tank level.

3.2.4      Motor Vehicle Filling
The filling of motor vehicles constitutes a major source of emissions at a service station. These
emissions result from two main processes;

⚫ 'whoosh' emissions; and
⚫ filling emissions
'Whoosh' emissions (Toxics Committee of the California Air Pollution Control Officers Association
1997) are emissions that occur when the fuel cap on a vehicle is removed prior to refuelling. These
emissions are subject to much debate currently as to actual levels and the factors that are used to
derive emission estimates. The CAPCOA study recognises these complexities and provides a range
for emissions estimates.

Filling emissions occur due to the displacement of vapours in the vehicle fuel tank as it is filled with
fuel and also due to evaporative emissions related to the fuel entering the tank.

Phase 2 vapour recovery is a control available to reduce fugitive emissions during fuel filling
operations. The displaced fuel vapour that occurs when vehicles are refuelling is captured via a
vapour return line attached to a vacuum pump within the fuel dispenser hose. These captured
vapours are returned to the underground fuel storage tank. These systems are capable of capturing
at least 85% of the displaced vapour (Toxics Committee of the California Air Pollution Control Officers
Association 1997).

The proponent has confirmed that phase 2 vapour recovery is to be included at the proposed service
station.

3.2.5      Fugitive Emissions
Fugitive emissions from service stations can occur as a result of nozzle drips, spit-back of petrol and
tank overflows (New South Wales. Environment Protection Authority 1996). These emissions can
occur at any location where vehicles are refuelled at a service station site.


3.3        Character of Emitted Chemicals
3.3.1      VOC Emissions
In terms of differing fuel types (ULP, LRP, Diesel), most emissions data available is for ULP with
emissions for ULP considered to be the dominant source of fuel emissions at a service station. For
the proposed service station, it is likely that the majority of fuel sold will be ULP-based (with 78% of
expected sales being associated with ULP-based fuels and the remaining 22% associated with diesel.



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                            Synergy Property Partners Pty Ltd- Air Quality Assessment - Proposed Service Station, 123 Eumundi-Noosa Road, Noosaville
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