Details of Waipa Plume Plotter

This page should be read in conjunction with How Plume Plotter Works. It provides more details specific to the Waipa version of Plume Plotter.

Stacks and buildings

The stack and buildings were included in the model as described in [1]. The image below shows the layout of the stack and buildings modelled. North is at the top; colours and numbers indicate the height of the buildings and the stack:

Stack measurements

There are three identical stacks a few metres apart, and these are modelled separately. The details below are taken from [1]:

The following values are used for albedo, Bowen ratio and roughness length. None of these are specified in [1]:

Emissions

The emission rates of pollutants are taken from [1] and [2]. The rates shown apply to each one of the three stacks:

PollutantEmission rate
per second
Oxides of nitrogen1.944 g
Particulates131 mg
Sulphur dioxide647 mg
Hydrogen chloride131 mg
Hydrogen fluoride13 mg
Carbon monoxide647 mg
Mercury388.9 μg
Cadmium and thallium64.7 μg
Other metals129.4 μg
Dioxins and furans625 pg

Background levels

The background levels of pollutants are taken from [1]:

PollutantBackground
concentration per m3
Oxides of nitrogen4 μg
ParticulatesN/A
Sulphur dioxideN/A
Hydrogen chlorideN/A
Hydrogen fluorideN/A
Carbon monoxideN/A
MercuryN/A
Cadmium and thalliumN/A
Other metalsN/A
Dioxins and furansN/A

Weather data

Weather data is taken from a local synoptic weather station: Hamilton Airport.

Upper air data is the latest reported by the Whenuapai upper air station.

References

1. ASSESSMENT OF THE EFFECTS OF DISCHARGES TO AIR FROM AN RDF ENERGY PLANT. Technical Report 3263.02R001. Terry Brady Consulting Ltd. November 2021.

2. Paewira Application No APP143988 Additional Information. September 2023.