Measured at Wollongong Was Used to Obtain a Complete Data Set to Estimate Background Air Quality for PM2.5. the Local Air Emissi
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measured at Wollongong was used to obtain a complete data set to estimate background air quality for PM2.5. The local air emission sources in proximity to the Project were also investigated using the web tool provided by the National Pollution Inventory (NPI) at (http://www.npi.gov.au). The search results showed that there are three emission sources in a 16km search radius of the Project: two petrol stations and a sewage treatment plant. Therefore it is concluded that the background air quality in the study area is anticipated to be without significant impact from human activities. This is in contrast to the air shed at Albion Park South and Wollongong which is influenced by industrial sources including Port Kembla steelworks, bulk port activities, coal terminals, asphalt plants, rail freight transport, and major arterial roadways. As such the use of the data from the OEH ambient air quality monitoring station data at Albion Park South is considered a conservative approach. Background Air Quality Concentrations Generally, air quality for Albion Park South and Wollongong can be described as good, with the exception of isolated high pollution days or extreme events as a result of isolated events such as dust storms and bushfires. A summary of air quality data at Albion Park and Wollongong for the period 2010-2015 is presented in Table 9-26 below. Table 9-26 Air quality at Albion Park and Wollongong since 2010 Statistics Annual Average Maximum 24-hour Annual Maximum 24- Unit (ug/m3) (ug/m3) Average hour (ppm) (ppm) Year PM10 PM2.5 PM10 PM2.5 SO2 NO2 SO2 NO2 Albion Wollongong Albion Wollongong Albion Park Park Park 2010 14.0 5.1 41.8 23.5 0.08 0.28 1.1 1.4 2011 13.6 4.6 51.0 17.7 0.06 0.21 1.0 1.3 2012 13.6 4.6 43.9 15.6 0.05 0.37 1.0 1.7 2013 14.7 7.7 69.0 88.4 0.07 0.42 0.9 2.0 2014 16.2 7.0 48.3 17.3 0.06 0.39 0.5 1.4 2015* 13.8 7.5 41.2 31.6 0.07 0.34 0.7 1.6 * Data for 2015 up to 15 December 2015. Year 2013 had the greatest maximum 24-hour PM10 and PM2.5 concentrations and higher concentrations of NO2 and SO2 than most other years in the period between 2010 and 2015. Accordingly 2013 has been selected as an appropriate year to represent background air quality for the Project and will provide a conservative approach for the assessment. Meteorology To characterise the local meteorology for the Project site Merimbula Airport Automatic Weather Station (AWS) has been referenced. The AWS at Merimbula is considered to be representative of the Project site. It is located 18km north, is positioned at a coastal location and the air quality at the station would most closely resemble that at the Project Site. 264 Climate statistics for Merimbula Airport AWS data shows that the hottest months are January and February with an average daily maximum temperature of 24.7ºC, and a daily minimum temperature of 15.2ºC. The coolest month is July, with an average daily maximum temperature of 16.5ºC, and a daily minimum temperature of 4.1ºC. The average annual rainfall is 761mm. To assess the local wind conditions, wind rose data for the period of 2010-2013 was obtained which showed that the predominant wind directions are from north east and south west. There are seasonal variations, with wind directions in the winter predominantly from west and south west, and in the summer predominantly from north east. Average wind speed is higher in summer than winter. A review of wind roses by year revealed that 2013 is a representative year for wind speed and direction distributions. Therefore it is a suitable year to be used for air dispersion modelling. In addition, the annual rainfall recorded in 2013 (810mm) and monthly averages of daily maximum and minimum temperature also confirm that 2013 is a representative meteorological year. Air Quality Assessment Criteria The air quality modelling for the Project has been undertaken in accordance with the Approved Methods for the Modelling and Assessment of Air Pollutants in New South Wales (EPA, 2005) (Approved Methods). The impact assessment criteria refer to the total pollutant load in the environment and have been developed by adding impacts from new sources to existing background levels. The air quality criteria relevant to this assessment include those related to particulate matter (PM), nitrogen dioxides (NO2), and sulphur dioxide (SO2) from fuel combustion. The NSW EPA ambient impact assessment criteria applicable to this Project are presented in Table 9-27. Table 9-27 NSW EPA Ambient Impact Assessment Criteria Pollutant Criterion Averaging Period 3 Nitrogen dioxide (NO2) 246 μg/m 1-hour average 62 μg/m3 Annual average 3 Sulfur dioxide (SO2) 712 μg/m 10-min average 570 μg/m3 1-hour average 228 μg/m3 24-hour average 60 μg/m3 Annual average Particulate matter < 10 μm 24-hour average (PM10) 50 μg/m3 (with maximum allowable exceedances of 5 days a year) 30 μg/m3 Annual average Particulate matter < 2.5 μm 25 μg/m3 24-hour average (PM2.5) 8 μg/m3 Annual average Carbon monoxide (CO) 30 mg/m3 1-hour average 10 mg/m3 8-hour average Air Quality Impact Assessment Methodology Emission sources and parameters, and the proposed operational scenario have been identified, and these have been compared to the air quality impact assessment criteria. 265 Dispersion Modelling Atmospheric dispersion modelling was undertaken using CALPUFF, which is a multi-layer, multi- species non-steady state puff dispersion model. The model set up for the air quality assessment has considered CALPUFF guidance notes published by NSW EPA in 2011. A maximum of 12 cruise ships are scheduled to visit Eden in 2017. To evaluate emissions under worst case meteorology (i.e. low mixing heights, calm, stable conditions) it has been assumed that one ship per day would be entering and leaving the port. This conservative approach has ensured that ship berthing will coincide with worst-case meteorological conditions. The Holland America cruise ship ‘Noordam’ is 20-30 percent larger (in terms of emissions) than the average cruise ships that will visit Eden in 2017. The Noordam has been selected to represent worst- case emission rates. The resultant emission rates when the ship is at berth and in transit are presented in Table 9-28. Table 9-28 Emission Rates (g/s) Residual oil Marine distillate Low sulphur oil Substance Main Auxiliary Main Auxiliary Main Auxiliary engine engine engine engine engine engine NOx 118.5 53 111.3 50.1 20.4 11.2 SO2 67.4 43.3 11.9 7.6 2.6 1.4 PM10 9.3 5.2 2.0 1.2 0.5 0.3 PM2.5 8.6 4.8 1.8 1.0 0.5 0.3 CO 3.3 4.0 3.3 4.0 9.2 5.0 The emission rates have been calculated for residual oil, marine distillate and low sulphur fuel. With the exception of carbon monoxide the emission rates for nitrous oxides, sulfates, PM10 and PM2.5 are consistently lower with low sulphur fuel. 9.7.2 Potential Construction Impacts The main air quality and amenity issues at the construction site for the Project will include the following: Visible dust plumes and dust settling on surfaces Elevated PM10 concentrations Exhaust emissions from plant and equipment Fugitive emissions during refuelling activities The majority of potential impacts associated with construction activities are generated by the movement of plant and equipment over temporary roads and open ground. Dust emissions will vary from day to day and will be dependent on the nature, type and duration of construction activity, and meteorological conditions. 266 Due to the unpredictability of the dust emissions and weather conditions, a qualitative approach has been adopted and construction activities have not been modelled. The approach for assessing construction related impacts on air quality associated with the Project has been based on Guidance on the assessment of dust from demolition and construction, Institute of Air Quality Management, London (IAQM, 2014). The aim of this approach was to identify risks to air quality and recommend appropriate mitigation measures. Fugitive emissions will result from the refuelling of plant and vessels during the construction phase. However the emissions from this source will be minor and not material to the air quality assessment. The remainder of potential emissions air quality impacts associated with the operation and use of construction plant and equipment have been assessed together. The plant and equipment that is likely to be utilised during the construction activities will include excavators, barges, backhoe dredges, a piling rig, heavy vehicles and tug boats. The construction activities will be undertaken in three main phases; mobilisation, dredging and piling. The IAQM assessment procedure has been adopted for assessing the risk to air quality associated with construction dust. The assessment includes working through a five step process that considered four main types of activities on the construction site (demolition, earthworks, construction and track-out). Three types of dust impacts were considered for each activity; 1. annoyance due to dust settling, 2. the risk to health effects due to an increase in exposure to PM10 3. harm to ecological receptors The findings are then used to define appropriate mitigation measures. A preliminary assessment using the IAQM approach indicated that all the proposed risks associated with the construction activities would be negligible.