porta bridgewater sawmill expansion - epa tasmania mouldings pty ltd, sawmill... · porta...

PROJECT: BRIDGEWATER SAWMILL EXPANSION

JOB NO: P18005

CLIENT: Porta Mouldings

PORTA BRIDGEWATER

SAWMILL EXPANSION

Environmental Effects Report

CBM Sustainable Design

PORTA BRIDGEWATER SAWMILL EXPANSION | ENVIRONMENTAL EFFECTS REPORT i

CBM Sustainable Design Pty Ltd

51 York St, PO Box 1971

Launceston Tasmania 7250 Australia

Telephone: (03) 63326988

Email: [email protected]

Date Purpose of Issue/Nature of Revision Revision No. Authorised by

25/07/2018

21/08/2018

10/09/2018

Draft submission to EPA

Updated following EPA comments

Updated following comments from EPA air emissions section

01

02

03

SD

SD

SD

mailto:[email protected]


PORTA BRIDGEWATER SAWMILL EXPANSION | ENVIRONMENTAL EFFECTS REPORT ii

Contents

1 Introduction ............................................................................................................ 1

2 Part A - Proponent Information .............................................................................. 2

2.1 Contact Details ............................................................................................... 2

2.1.1 Proponent ................................................................................................ 2

2.1.2 Consultant ............................................................................................... 2

3 Part B – Proposal Description ................................................................................ 3

3.1 Description of proposed activity ...................................................................... 3

3.1.1 General description.................................................................................. 3

3.1.2 Industry standards and guidelines ........................................................... 6

3.1.3 Timeframe ............................................................................................... 7

3.1.4 Operating hours ....................................................................................... 7

3.1.5 Production rates ...................................................................................... 7

3.2 Proposal area ................................................................................................. 7

3.2.1 General site description ........................................................................... 7

3.2.2 Local climate............................................................................................ 8

3.2.3 Current and historical site use ............................................................... 11

3.2.4 Land tenure ........................................................................................... 11

3.2.5 Land zoning ........................................................................................... 12

3.2.6 Surrounding land use ............................................................................. 12

3.2.7 Geology and soils .................................................................................. 13

3.3 Rationale and alternatives ............................................................................ 13

3.4 Planning information ..................................................................................... 14

3.5 Existing activity ............................................................................................. 14

3.5.1 Current operations ................................................................................. 14

3.5.2 Environmental compliance ..................................................................... 15

4 Part C – Potential environmental effects .............................................................. 16

4.1 Flora and fauna ............................................................................................ 16

4.2 Aquatic environment and stormwater ............................................................ 16

4.3 Significant areas ........................................................................................... 17

4.4 Air emissions ................................................................................................ 17

4.4.1 Gas fired boiler ...................................................................................... 19

4.4.2 Reconditioner ........................................................................................ 19


PORTA BRIDGEWATER SAWMILL EXPANSION | ENVIRONMENTAL EFFECTS REPORT iii

4.4.3 Biomass boiler ....................................................................................... 20

4.4.4 Sawmill .................................................................................................. 20

4.4.5 General .................................................................................................. 21

4.5 Liquid effluent ............................................................................................... 21

4.6 Solid wastes ................................................................................................. 23

4.7 Noise emissions ........................................................................................... 24

4.8 Transport impacts ......................................................................................... 26

4.9 Other off-site impacts .................................................................................... 27

4.10 Hazardous substances ................................................................................. 27

4.11 Site contamination (historical) ....................................................................... 27

4.12 Heritage ........................................................................................................ 28

4.12.1 European heritage ................................................................................. 28

4.12.2 Aboriginal heritage ................................................................................. 28

4.13 Sites of high public interest ........................................................................... 29

4.14 Monitoring ..................................................................................................... 29

4.15 Rehabilitation ................................................................................................ 29

5 Part D – management commitments .................................................................... 30

6 Part E – Public and stakeholder consultation ....................................................... 31

7 References .......................................................................................................... 32

List of Figures

Figure 1 Process flowchart for proposed saw milling operations and biomass boiler..... 4

Figure 2 Schematic diagram of the additional saw milling equipment to be installed ..... 5

Figure 3 Process flowchart for existing green sawn operations with proposed changes

highlighted in yellow ...................................................................................................... 6

Figure 4 Average monthly rainfall for Hobart (Ellerslie Rd) Bureau of Meteorology site

for the period 1882 – 2018 ............................................................................................ 8

Figure 5 Rose of average wind direction versus wind speed at 9am at the Hobart

(Ellerslie Rd) Bureau of Meteorology site for the period 1882 – 2010 ............................ 9

Figure 6 Rose of average wind direction versus wind speed at 3pm at the Hobart

(Ellerslie Rd) Bureau of Meteorology site for the period 1882 – 2010 .......................... 10

Figure 7 Average monthly minimum and maximum temperatures at the Hobart

(Ellerslie Rd) Bureau of Meteorology site for the period 1882 – 2010 .......................... 11

Figure 8 Cadastral parcels with zoning overlay in the vicinity of the subject site, which

is shown with a hashed outline ................................................................................... 13

List of Tables


PORTA BRIDGEWATER SAWMILL EXPANSION | ENVIRONMENTAL EFFECTS REPORT iv

Table 1 Summary of atmospheric emissions ............................................................... 18

Table 2 Relevant receivers in proximity to the project ................................................. 19

Table 3 Sampling results of condensate effluent and comparision to industry averages

from Dare et al. (2003) ................................................................................................ 22

Table 4 Summary of noise generating equipment SPLs .............................................. 24

Table 5 Summary of predicted noise emissions at relevant receptor locations and

relevant criteria ........................................................................................................... 25

Table 6 Traffic movements associated with current site operations ............................. 26

Table 7 Traffic movements associated with expanded site operations ........................ 26


PORTA BRIDGEWATER SAWMILL EXPANSION | ENVIRONMENTAL EFFECTS REPORT 1

1 Introduction

Porta Mouldings operates an existing timber drying, conditioning and finishing

operation at 112 – 114 Cove Hill Rd, Bridgewater. This proposal involves the

installation of saw milling equipment at the site and an increase in the maximum

production limit from 4,500 m2 to 7,000 m2 per annum.

A Notice of Intent was submitted to the Environment Protection Authority (EPA) on

17/04/2018, and a determination was subsequently made that the proposal would be

assessed as a class 2A assessment under the Environmental Management and

Pollution Control Act 1994 (EMPC Act). Guidelines for preparation of the Environmental

Effects Report (EER) were received on 18/05/2018.

This EER has been developed in accordance with these guidelines for the purpose of

informing the Board of the EPA of the environmental effects and proposed

management measures associated with this project.

An assessment of potential impacts of the project on matters of national environmental

significance under the Environment Protection and Biodiversity Conservation Act 1999

has been undertaken. It concluded that there is a very low risk of significant impacts to

Matters of National Environmental Significance, and thus a referral to the

Commonwealth under this Act is not required.



2 Part A - Proponent Information

2.1 Contact Details

2.1.1 Proponent

Name of proponent: Porta Properties No 2 Pty Ltd

Registered address of proponent 224-256 Heidelberg Road, Fairfield,

Victoria 3078

Postal address of proponent P.O. Box 195 Fairfield, Victoria 3078

ABN number 58 144 694 824

ACN number (where relevant) 144 694 824

Contact person’s details:

Name Mr Warrick Batt

Telephone number 03 9488 3222

Email address [email protected]

2.1.2 Consultant

This EER has been prepared by Sam Dingemanse of CBM Sustainable Design

([email protected], 03 6332 6988).

mailto:[email protected]



3 Part B – Proposal Description

3.1 Description of proposed activity

3.1.1 General description

The project involves the installation of saw milling equipment at Porta’s Bridgewater

site to enable the milling of hardwood logs in addition to its existing timber drying,

conditioning and finishing operations.

This additional equipment consists of:

Twin circular saw for ripping whole logs

Twin band saw for further ripping of large product

Single circular saw (one-man bench) for ripping smaller product

Multi saw edger for finishing product

Various chain and belt driven conveyors and sorting tables for moving product

within the shed.

Figure 1 shows the process flowchart for this additional equipment, as well as the

various product and waste streams (solid, liquid and air emissions). This equipment,

with associated control systems and electrical services will be housed in a new 2,200

m2 partially open sided shed. The equipment is being purchased directly from Barber’s

Sawmill in Launceston, which is being decommissioned.

The following items will also be included in the proposed expansion:

Waste chipper plant and feed / output conveyors housed in an enclosed

structure adjacent to the shed;

Sawdust collection and storage system;

Additional storage building of approx. 1,800 m2 to accommodate increased

product volumes;

New administration building of approx. 130 m2;

Log storage area of approx. 2400 m2, with irrigation from stormwater pond;

Installation of biomass boiler fed from onsite wood waste;

Installation of 500 L fuel storage container;

Second site entrance to allow separation of light and heavy traffic flows;

Enlargement of stormwater pond and reconfiguration to water retention for

onsite reuse (log spraying).

This will allow Porta to receive and saw green hardwood logs directly, eliminating the

need to outsource this component of its timber supply chain.



Figure 1 Process flowchart for proposed saw milling operations and biomass boiler

The general milling process is shown in Figure 2 and is described as follows: large

whole logs will be loaded onto a rail-mounted sled which feeds the twin circular saw for

ripping. The ripped timber then passes via conveyor to the twin band saw, where it is

ripped into smaller sections. Smaller logs may bypass the twin circular saw and be fed

to the twin band saw directly. The product then again travels via conveyor to the single

circular saw (one-man bench), where it is again ripped to approximately the correct

size for the desired product. Some product may be stacked and taken from the mill at

this stage if rough-sawn timber is desired. Conveyors then take the remaining product

to the edger (multisaw), where it is fed by hand for four-sided thicknessing. The output

product is then stacked to be dried or sent to the existing mill for further processing.

Offcuts from these various stages are either automatically or manually placed onto the

chipper feed conveyor, where it is fed from the mill shed to the chipper shed for

chipping. Output feed from the chipper is then fed via conveyor to a storage bund.



Figure 2 Schematic diagram of the additional saw milling equipment to be installed

The proposed layout of the new facilities at the Bridgewater site is shown in drawings

A101 and A102 attached as Appendix 1.

The volume of product produced will increase to a maximum of 7,000 m3 per annum. In

addition, there will be an increase in the volume of raw material received to the site to a

maximum of 17,500 m3 per annum, due to the fact that green logs will now be received.

Figure 3 shows the process flowchart for the existing site operation, which involves air

and kiln drying green sawn timber, and sorting, docking and packing of dry product for

dispatch. The yellow highlighted processes are proposed changes/additions through

this project, being the installation of a biomass boiler to supplement the current gas

boiler and reconfiguration of the kiln condensate to report to the stormwater pond.



Figure 3 Process flowchart for existing green sawn operations with proposed changes highlighted in yellow

3.1.2 Industry standards and guidelines

This activity will be undertaken in accordance with the Sawmill Environmental Code of

Practice 1995, which documents acceptable standards for sawmills in regards to the

management of potential environmental impacts. The code has been referenced

throughout this report to demonstrate compliance with the acceptable standards of the

code.

Porta is committed to sourcing timber from sustainable and environmentally

responsible resources. Porta holds Chain of Custody under the three national and

internationally recognised and accredited organisations:

Forest Stewardship Council® (FSC®)

Australia Forest Certification Scheme (AFS)

Programme for Endorsement of Forest Certification (PEFC™)



3.1.3 Timeframe

Upon receipt of all approvals, the timeframe for the project is approximately 11 months,

during which time the currently operations will continue as normal. It consists broadly of

the following:

Site civil works – 2 months

Construction of facilities and upgrade of site electrical infrastructure – 6 months

Commissioning of saw milling equipment – 3 months.

The operation of the redeveloped site will continue for the foreseeable future.

3.1.4 Operating hours

The current site EPN has restricts operational activities to the following times:

0700 to 1800 hours Monday to Friday;

0900 to 1800 hours on Saturday;

1000 to 1800 hours on Sundays or public holidays.

The operation of kilns, reconditioners and boilers are permitted 24 hours per day,

seven days per week.

There is no there is no proposed change to these operating hours as a result of this

proposal.

3.1.5 Production rates

The current site EPN limits production to 4,500 m3 per annum. This proposal includes a

request to increase the annual production to 7,000 m3.

3.2 Proposal area

3.2.1 General site description

The site consists currently of two titles: 144927/4 and 144927/5, with a total area of 6.51

ha. It is located in an industrial precinct and is heavily modified from previous

agricultural activities, with no remnant native vegetation present at the site.

The northern half of the site contains buildings, timber storage and access roads, while

the southern half of the site is generally undeveloped other than an existing stormwater

pond at the south eastern corner (approximate capacity of 1.3 ML). The proposed

development will predominantly occur in this undeveloped southern area.



The site is relatively flat with a minor gradient falling to the south east. A survey was

conducted of the southern half of the site, this area ranges from 51m AHD at the north

west of this area to 45m AHD to the south east of the site.

The nearest surface water body is the Jordan river located approx. 350m to the east of

the site.

The land capability class is 5+4, being at least 60% Land unsuited to cropping and with

slight to moderate limitations to pastoral use, up to 40% Land well suited to grazing but

which is limited to occasional cropping or a very restricted range of crops.

3.2.2 Local climate

The nearest Bureau of Meteorology weather station with comprehensive records is

Hobart (Ellerslie Rd). This station is approximately 20km south of the subject site.

Rainfall is very consistent throughout the year, with a mean annual average of 614mm

(Figure 4).

Figure 4 Average monthly rainfall for Hobart (Ellerslie Rd) Bureau of Meteorology site for the period 1882 – 2018



Winds are very consistent in the morning, being predominantly north and north-

westerly (Figure 5). In the afternoon the wind direction is more varied, being

predominantly north-west and south-east (Figure 6).

Figure 5 Rose of average wind direction versus wind speed at 9am at the Hobart (Ellerslie Rd) Bureau of Meteorology site for the period 1882 – 2010



Figure 6 Rose of average wind direction versus wind speed at 3pm at the Hobart (Ellerslie Rd) Bureau of Meteorology site for the period 1882 – 2010

Temperatures in the region are typical of a cool temperate climate, with an average

monthly maximum temperature range of 11.7 °C to 21.7 °C and an average monthly

minimum temperature range of 4.6 °C to 12.1 °C (Figure 7).



Figure 7 Average monthly minimum and maximum temperatures at the Hobart (Ellerslie Rd) Bureau of Meteorology site for the period 1882 – 2010

3.2.3 Current and historical site use

The current use of the site is a timber processing facility. It was constructed in 2006

under planning permit DA25/244 issued by the Brighton Council.

The land surrounding the site was approved to be developed as a wrecking yard,

stables, training track and caretaker’s residence in 1986 (DA1986/03). The wrecking

yard building and caretaker’s residence are still present adjacent to the site, however

the wrecking yard building is unused and dilapidated. The Brighton Council has

confirmed that the caretaker’s residence (110 Cove Hill Rd) is approved only as

ancillary or incidental to an industrial use (given that residential use is prohibited in the

industrial zone) and thus not been considered as sensitive receiver in respect of the

site emissions.

The lot was created in 1997 when a subdivision of the land was approved (planning

permit SA1997/10) to create 7 lots and retain the wrecking yard building and

caretaker’s residence on a balance lot.

3.2.4 Land tenure

The site consists currently of two titles: 144927/4 and 144927/5. Both sites are owned by

Porta Properties No 2 Pty Ltd, the proponent of this development.



3.2.5 Land zoning

The property is zoned General Industrial under the Brighton Interim Planning Scheme

2015.

3.2.6 Surrounding land use

The site is located in an industrial precinct, in an area of general industrial zoning. The

adjacent properties to the east and west of the site are currently undeveloped. A large

quarry is situated to the north-east of the site, and a small farm is located to the north-

west.

There is light industrial zoning to the south of Cove Hill Rd, in which a number of

manufacturing and fabrication operations are located.

There is general residential area south of the light industrial precinct. The nearest

residence is approximately 250m from the site boundary. No other sensitive uses exist

in proximity to the site.

There is a waste transfer station located to the south-east of the site, and open space

zoned land further east, forming the riparian zone of the Jordan River.



Figure 8 Cadastral parcels with zoning overlay in the vicinity of the subject site, which is shown with a hashed outline

3.2.7 Geology and soils

The geology of the site is mapped as Tholeiite basalt (Forsyth, 2002). The geotechnical

investigation undertaken for the project identified silty and sandy clay to a depth

ranging from 0.7 – 1.7m, with underlying weathered rock (Strata Geoscience and

Environmental, 2018). It assessed the erosion potential of the soil as ‘moderate -

dispersive soil phases possible’.

There are no areas mapped as high probability of acid sulphate soil, nor are there any

acid sulphate soil sites recorded in the Tasmanian Acid Sulfate Soils Information

database, in proximity of the site.

3.3 Rationale and alternatives

The key driver of the project is to allow Porta to receive and saw green hardwood logs

directly, eliminating the need to outsource this component of its timber supply chain.



Currently the site receives sawn timber from other sawmills, which then undergo further

processing, and this project will ensure that Porta has control over its timber supply

chain from log to finished product at the one facility.

The proponent also considered purchasing an existing sawmilling operation. This

would have negated the need to obtain approvals for, and construct the sawmill. There

would however have been logistical and management challenges and costs with

operating two discrete operations.

3.4 Planning information

The site is zoned General Industrial under the Brighton Interim Planning Scheme 2015.

Resource Processing is a permitted use in this zone. There is no proposed change to

this existing use as a result of this project as the site upgrade does not change the

major activity under taken at the site (timber processing). The site operates under an

existing planning permit DA05/244 dated 31/08/2005 and EPN 8779/1 dated

20/02/2013.

A planning application for the proposed works was submitted to Brighton Council on

the 5th June 2018. This included a Planning Application – Supporting Submission

(attached as Appendix 2) which provides a detailed assessment of the development

against the relevant sections of the planning scheme.

3.5 Existing activity

3.5.1 Current operations

Porta currently outsources milling of its hardwood logs to other sawmills, and receives

sawn green hardwood at the Bridgewater site. This product then undergoes air and kiln

drying, conditioning and finishing at the site, prior to transportation interstate for further

finishing at Porta’s moulding factory in Melbourne, Victoria and/or for sale as final

product. This is described further in section 3.1.1.

The site was constructed in 2006 and consists of the following:

Main product finishing building with adjacent office and amenities area;

Two buildings for product storage;

Kiln and reconditioner (total capacity 60 m3) driven from 450 kW gas boiler

Timber yard for air drying of timber.



3.5.2 Environmental compliance

Environmental compliance of the operation is currently regulated under EPN8779/1

dated 20/02/2013. The maximum allowable production is 4,500 m3 of product per

annum. There is no requirement for environmental monitoring under the current permit.

There have been no known public complaints regarding the site operations since its

establishment in 2006.

There have also been no known breaches of the regulatory conditions or

contraventions of environmental law.



4 Part C – Potential environmental effects

4.1 Flora and fauna

The site is heavily modified, with no remnant native vegetation present. This is

reflected by the TASVEG mapping which shows the entire site as Urban areas (FUR).

As such, no native vegetation will be cleared as a result of the proposed works.

A Natural Values report (attached as Appendix 3) was generated for the subject site

and 500m buffer from the site boundary. There are no threatened flora or fauna

species, raptor nests or threatened communities recorded within this search area.

Thus, there is no risk of impacts to flora and fauna resulting from the proposed works.

4.2 Aquatic environment and stormwater

The nearest waterway to the site is the Jordan River, located approximately 350 m to

the east of the site boundary. The Jordan River has its headwaters at Lake Tiberias,

around 40km to the north-east of the site. It eventually empties into the River Derwent

at Herdsmans Cove, to the south of the site.

Currently, all site stormwater other than roof catchment is diverted via open swale drain

to the stormwater detention pond located at the south east of the site. This has a

capacity of approximately 1.3 ML. There is an additional 200 kL of tank water storage

fed from the main building roof. This is used as the water supply for the reconditioner.

A 150 mm diameter pipe releases stormwater from the detention pond to the

stormwater swale in the Cove Hill Road reserve. This stormwater drain is assumed to

eventually drain to the Jordan river to the east of the site.

It is proposed to expand the existing stormwater system to ensure it complies with the

Stormwater Management Code in the Brighton Interim Planning Scheme 2015 for the

redeveloped site, as well as providing water storage for maintaining moisture levels in

logs stored on site.

Specifically, the existing pond storage will be increased to 1.9 ML by enlarging the

surface footprint, and a retention volume will be developed by installing a concrete pit

surrounding the discharge outlet. This will allow the pond to function as both retention

(for reuse of stormwater for log watering) and detention. In addition, another 200 kL of

tank water storage will be installed, to be fed from the new building roof.

During the pond expansion, a clay lining will be constructed at a suitable thickness to



minimise permeability and the risk of stormwater loss to groundwater.

This additional storage was calculated to comply with the Stormwater Management

Code requirements of being able to accommodate a storm with an ARI of 50 years.

The proposed storage can provide a maximum of 120 minutes of detention at this

storm intensity.

The pond will improve stormwater quality by settling out suspended solids and promote

predominantly aerobic biological treatment of nutrients and organic pollutants in the

stormwater. This will effectively ensure that on the occasions when stormwater does

leave the pond via the overflow connection to the road stormwater swale drain, the

quality has been improved via a reduction in suspended solids and nutrients.

In order to minimise organic contamination of stormwater, the site excluding the log

storage area will be tidy by minimising the accumulation uncontrolled wood waste such

as sawdust, woodchips, offcuts and bark. A layer of wood waste will be maintained at

the log storage area to prevent any gravel from being transferred with the logs and

damaging the saws. The log storage area will drain to the stormwater pond, which will

prevent any stormwater runoff from this area leaving the site directly.

Commitment 1 – the site will be kept tidy by removing and disposing of uncontrolled

wood waste from the roadways, non-log storage areas and undeveloped areas.

4.3 Significant areas

The proposal site is not within or adjacent to any reserved areas. The nearest reserved

area is a public reserve located 150 m to the south-east of the site at its nearest point.

Thus, there is no potential for adverse impacts on any reserved areas.

4.4 Air emissions

Atmospheric emissions will occur from a number of sources at the redeveloped facility,

with the major sources of emissions being combustion products from steam/hot water

generation, sawdust from milling operations and general dust from use of the internal

roads and laydown areas. These are discussed further below, and summarised in

Table 1.

The site currently uses approximately 4,500 GJ of natural gas per annum. This will

decrease to 4000 GJ, reflecting the fact that the gas driven boiler driving the kilns will

be replaced with a biomass boiler, as well as an increase in the gas usage for the gas

burners in the reconditioner.



Table 1 Summary of atmospheric emissions

Equipment or process

Type Composition Quantity

Reconditioner Fugitive vapour emissions when doors are opened

Gaseous combustion products from the exhaust.

Water vapour with some volatile organic compounds (VOCs)

The vast majority of combustion products is CO2 and water vapour. Minor quantities of CO and NOx emissions.

Approx. 100,000 L per annum

134 t of CO2 per annum

Kiln Point vapour emission from roof vents

Water vapour Approx. 1.1 ML per annum

Gas boiler Gaseous combustion products from the exhaust.

The vast majority of combustion products is CO2 and water vapour.

Minor quantities of CO and NOx emissions.

97 t of CO2 per annum

Biomass boiler

Gaseous combustion products from the exhaust.

The vast majority of the combustion products are CO2 and water vapour.

Minor quantities of CO, PM and NOx emissions.

Unknown

Sawmill Minor fugitive sawdust emissions from milling operations

Hardwood sawdust Unknown

General Dust Gravel fines from roadways

Unknown

Drawing A109 Air Emissions attached as part of Appendix 1 shows the location of

these atmospheric emissions on the site, and the proximity to relevant receiver

locations in the vicinity.

These include the surrounding industrial activities (including residences located in the

general industrial zone that are approved for use only as caretaker’s residences

ancillary to an industrial use) as well as the nearest sensitive receiver (residence) to

the south (Table 2).



Table 2 Relevant receivers in proximity to the project

Designation Description Use Distance from project site boundary

Easting Northing

A Nearest residential boundary

Residential 250 m 520968 5268312

B Western dwelling 1 Industrial 75 m 520731 5268706

C Western dwelling 2 Industrial 190 m 520624 5268770

D Engineering workshop

Industrial 230 m 520574 5268686

E Polyfoam manufacturing

Industrial 30 m 520767 5268559

F Landscaping/ nursery

Industrial 190 m 521142 5268575

4.4.1 Gas fired boiler

The two drying kilns are heated using hot water from a gas fired boiler. This consumes

approximately 1,900 GJ of natural gas per annum.

The combustion of natural gas (predominantly methane) produces carbon dioxide and

water. Minor amounts of nitrogen oxides (NOx) and carbon monoxide are also

produced, but this is of minimal quantities in modern gas fired boilers.

This proposal includes the replacement of the gas fired boiler with a biomass boiler,

and thus emissions from this activity will cease at this time.

The kilns and boiler have been in operation at the site for over 10 years, in which time

there have been no complaints for neighbouring properties regarding associated air

emissions. This demonstrates that the emissions do not create an environmental

nuisance.

4.4.2 Reconditioner

The reconditioner uses steam produced by two gas-fired immersed tube burner steam

baths. This consumes approximately 2,600 GJ of natural gas per annum. As with the

gas boiler, carbon dioxide and water are produced during the combustion of natural

gas, with minimal quantities of NOx and CO also produced.

Vapour is released from the reconditioner when the doors are opened at the

completion of each cycle. This vapour is predominantly water, with small quantities of

VOCs which are released from the timber during the reconditioning process.



As with the gas-fired boiler, air emissions associated with the reconditioner have never

attracted complaints from neighbouring properties, demonstrating that they do not

create an environmental nuisance.

4.4.3 Biomass boiler

This proposal incorporates the replacement of the gas fired boiler with a biomass fired

boiler. This would be fed from woodchips and sawdust produced on site, with a total

consumption of approximately 450 t of wood waste per annum.

The boiler will be rated at 145kW, and will produce water at 85 °C, filling a 1000 L

insulated hot water buffer tank. This tank will supply hot water for the two drying kilns,

as well as supplying a heat exchanger for the reconditioning kiln.

The boiler will have automated fuel feed supply and ash removal to maximise

combustion efficiency and minimise adverse atmospheric emissions. It should be noted

that wood waste is a renewable energy source, and thus the replacement of the natural

gas fired boiler will reduce associated greenhouse gas emissions by approximately 97 t

CO2 e per annum.

Emission control most suited to the planned boiler system is a baghouse fabric filter

system. Fabric filters installed as a baghouse are better able to reduce fine particulate

matter (PM) emissions than other emissions control solutions and are the intended

choice in this application. Depending on the design and choice of fabric, control

efficiencies of more than 99 percent for PM2.5 and PM10 can be achieved by fabric

filters and baghouses.

As such, the proposed biomass boiler can be engineered to ensure its compliance with

the Environment Protection Policy (Air Quality) 2004 in-stack concentration limit of

100mg/m3 for particulate matter.

Commitment 2 – The biomass boiler will be designed, including a baghouse fabric filter

system if required, to ensure it complies with an in-stack concentration limit of

100mg/m3 for particulate matter.

4.4.4 Sawmill

The capture and disposal of sawdust is already well managed at the facility, through a

blower system which captures the sawdust at each saw and transports it to a covered

storage hopper. This system will be expanded to incorporate the proposed additional

saws, and thus will effectively manage sawdust emissions.



The site currently produces approximately 240 t of sawdust per annum. It is taken off-

site and beneficially reused as animal bedding.

Commitment 3 – A sawdust capture and storage system will be installed on all

additional saw milling equipment. This system will be serviced and maintained as per

manufacturer’s recommendations, to ensure system continues to operating effectively.

4.4.5 General

Dust will be produced from vehicle operations on the internal roads and laydown areas.

Vehicles include staff and service passenger vehicles, truck movements for transport of

incoming and outgoing product and forklift usage between the storage sheds.

Dust generation will be minimised by appropriate maintenance of the internal road

system and implementing a speed restrictions on vehicles. Dust generation will be

monitored by staff, and roads will be watered if dust generation becomes a nuisance to

surrounding businesses.

Commitment 4 – Internal access roads will be appropriately maintained to minimise

dust generation.

Commitment 5 – Visual monitoring of dust generation will be conducted by staff. If it is

determined, through visual monitoring or public complaints, that dust from access

roads is an nuisance to neighbours, then roads will be swept or watered to mitigate

dust generation.

Commitment 6 – Internal site traffic will be speed limited to 10 km/hr.

Commitment 7 – The log yard will be maintained by regular removal of loose wood

waste, such that fugitive dust emissions are kept to a minimum.

Commitment 8 – Dust suppression in the log yard will be assisted by the use of water

irrigation spray.

4.5 Liquid effluent

The site is serviced for sewerage and water, and human effluent from the staff

amenities is discharged to sewer.

The majority of water usage at the site is for the operation of the reconditioner. The site

uses approximately 250 kL per annum of water from the mains connection, which



provides any shortfall from the water collected in the 200 kL of tank storage connected

to the building roofs. Mains water usage is not expected to substantially increase with

the proposed site upgrade as the additional water required for log spraying will be

provided by the stormwater pond and additional 200 kL of tank storage connected to

the new shed roofs.

The only liquid effluent produced by the proposed activity is the condensate produced

by the reconditioner. This condensed vapour from the timber reconditioning process is

comprised of water vapour and a range of organic compounds (carbohydrates, acids)

that leach from the timber (Dare et al., 2003).

The condensate was sampled on 28/06/2018 and analysed for a range of physical and

chemical properties. These results and their comparison to industry averages are

summarised in Table 3.

Table 3 Sampling results of condensate effluent and comparision to industry averages from Dare et al. (2003)

Analyte Reconditioner condensate Dare et al. (2003) typical composition

pH 4.12 4.7 – 8.0

Chemical oxygen demand (COD) (mg/L)

2000 750 - 4700

Biochemical oxygen demand (BOD) (mg/L)

770 45 – 2160

Total suspended solids (TSS) (mg/L)

198 -

This effluent will be produced at a rate of approximately 10,000L per week. It is

proposed to transfer this effluent from the existing storage tanks via a swale drain to

the on-site stormwater pond. The stormwater pond is designed to retain site

stormwater runoff for onsite reuse (log stockpile watering).

As discussed in section 4.2 the existing pond storage will be increased to 1.9 ML by

enlarging the surface footprint. The pond will theoretically will receive 29.6 ML of

stormwater runoff per year based on the site area of 6.5 ha, average site runoff

coefficient of 0.74 and the mean rainfall of 614mm. This demonstrates that there will be

substantial dilution of the approximately 0.52 ML of condensate effluent produced per

annum with the stormwater collected. This will act to increase the pH of the retained

stormwater/effluent to close to neutral. In addition, the retention of the diluted effluent

will allow the settling of suspended solids and will promote aerobic biological

breakdown of the organic compounds. The pond is expected to operate predominantly

aerobically, due to its shallow nature and the expected regular wind action on the pond

surface, which will promote aeration and mixing of the surface water layer.

There is currently no reuse of stormwater from the pond. However it is proposed to



reuse stormwater to maintain log moisture levels prior to milling, via spraying at the log

storage area. There is a potential that the surface of the log storage area will

experience organic enrichment from the stormwater reuse. However this is limited to

the log reuse area, and as log storage area drains to the stormwater pond, no enriched

stormwater will leave the site via this reuse mechanism.

Thus, even though the effluent stream will be improved via sediment and organics

removal in the stormwater pond, it will rarely leave the site, as it will be continually

reused on site.

4.6 Solid wastes

The current site operation produces mainly wood waste streams with a minor amount

of non-wood solid waste. Approximately 240 t (800 m3) per annum of sawdust is

produced, which is captured and stored in the collection and storage system. This is

taken off-site and beneficially reused as animal bedding. Approximately 1,250 m3 of

timber offcuts are produced per annum, which is gifted to employees for use as fuel for

domestic wood heating. 150 m3 per annum of non-wood solid wastes are produced at

the site, which includes waste plastic wrapping and strapping, and general refuse. This

is stored in a skip bin and periodically collected and disposed to landfill by a waste

contractor.

There will be a substantial increase in the volume of solid wood wastes produced at the

site due to an increase in the raw material to be processed. Solid wood wastes will

predominantly be in the form of hardwood sawdust and woodchips. Sawdust is

produced from the individual saws, while all waste timber and offcuts will be run

through the chipper to create woodchips.

At the maximum production capacity of 7,000 m3 processed timber, there is expected

to be approximately 7,000 m3 of woodchips and 3,500 m3 of sawdust produced per

annum. The volume of non-wood waste will increase in line with production to

approximately 230 m3 per annum. The composition of this waste will not change, and

will continue to be accumulated in a skip bin for collection and disposal by a waste

contractor.

The Sawmill Environmental Code of Practice recommends a waste management

strategy with a hierarchy of controls, as follows:

Waste minimisation;

Waste reuse and recycling;

Waste treatment to reduce hazard or nuisance;

Waste disposal.



Porta will adhere to this strategy by prioritising waste minimisation through efficient and

well-planned operations, and ensuring waste products are beneficially reused where

practicable.

The management of sawdust is discussed in section 4.4.4. All sawdust produced will

be sold for beneficial reuse as horticultural supplies and animal bedding, thus

preventing its disposal in landfill.

A proportion of the woodchips produced will be reused as a fuel source for the biomass

boiler (approximately 450 t or 1,200 m3. Woodchips produced beyond the biomass fuel

requirement will be sold for beneficial reuse and/or sold to woodchip exporters, and

thus none will be disposed of in landfill.

The biomass boiler will produce ash as a combustion by-product. This will be

automatically transferred to a skip bin by screw conveyor. The annual production

quantity is expected to be 13.5 t. This will be disposed to landfill by a waste disposal

contractor.

4.7 Noise emissions

A noise assessment was undertaken by NVC (attached as Appendix 4) which included

undertaking noise measurements of the existing facility as well as proposed additional

equipment (currently still operating at Barber’s Sawmill in Launceston). The sound

pressure levels (SPLs) of this equipment with the proposed building layout was

modelled using iNoise software to predict noise emissions for the completed project.

Ambient noise levels at the nearest residential boundary were also measured.

This report includes details of all fixed and mobile noise sources from the current

operation and the proposed additional equipment. A summary of the noise-generating

equipment and their SPLs is provided in Table 4.

Table 4 Summary of noise generating equipment SPLs

Equipment SPL SWL (dBA)

Existing facility

Cut-off saw 104

Exhaust fan 104

Additional equipment

Twin circular saw 108

Twin band saw 116

Single circular saw 109

Multisaw edger 110

Chipper 119



The proposed location of the noise-generating equipment, as well as surrounding noise

receivers relevant to the proposal are shown in Drawing A110 Noise Emissions Plan,

attached as part of Appendix 1.

From this modelling, noise emissions from the proposed operations were predicted at

the relevant receiver locations nominated for the project (Table 2 and Table 5).

Relevant noise emission limit criteria were obtained from the existing site EPN and the

EER guidelines provided by the EPA. These criteria are 57 dBA at the nearest

sensitive receiver (5 dBA above the measured ambient noise level of 52 dBA) and 65

dBA at surrounding industrial premises.

Outputs from the modelling are provided in the attached report and predicted noise

emission impacts at relevant receivers are summarised in Table 5.

Table 5 Summary of predicted noise emissions at relevant receptor locations and relevant criteria

Description Nearest sensitive receiver

West dwelling 1

West dwelling 2

Engineering workshop

Polyfoam Landscaping supplies

Predicted SPL (dBA) 50 58 56 53 65 57

Noise emission limits (dBA)

57 65 65 65 65 65

Exceeds limits? No No No No No No

This modelling demonstrates that the noise emissions from the completed project are

predicted to be below the noise emission limits at all relevant receiver locations, and

thus are compliant with the existing EPN and EER guidelines. In addition, the modelling

is conserved conservative for the following reasons:

Model assumes that all roller doors are open when they may be closed;

Model assumes that all equipment is operating concurrently, which is unlikely to occur;

Model assumes that there is no additional screening from the log stockpile, which is likely to be located between the sawmill shed and the residential area to the south;

Model assumes no internal screening within the shed. There is likely to be some screening from the proposed equipment layout.

A number of recommendations were proposed in the report, and form management

commitments of this proposal.

Commitment 9 – Ensure operation of milling equipment does not occur outside of the

hours allowed by the existing site EPN.



Commitment 10 – Use material stockpiling (the long-term log storage yard) to afford

further screening to the residences where practicable.

Commitment 11 – Conduct a noise survey of the operations once the new site is

operating.

4.8 Transport impacts

Current site traffic movements are provided in Table 6. These consist of staff

passenger vehicle movements and truck movements for incoming and outgoing

product transport. There are additionally minor miscellaneous traffic movements.

Table 6 Traffic movements associated with current site operations

Traffic movements Frequency

Staff 15 vehicles per day

Incoming green sawn timber from saw mill

4 trucks per week

Outgoing product 4 trucks per week

Outgoing wood waste 1 truck per week

Service, miscellaneous deliveries

2 vehicles per week

Proposed site traffic movements for the expanded site operations are provided in Table

7. There will be a moderate increase in staff traffic movements, reflecting the increased

staffing at the site, and a moderate increase in truck movements for incoming and

outgoing product transport and wood waste reuse.

Table 7 Traffic movements associated with expanded site operations

Traffic movements Frequency Comments

Staff 25 vehicles per day

Incoming green sawn timber from saw mill

6 trucks per week Increase in product deliveries due to receipt of logs

Outgoing product 6 trucks per week Increase in product dispatch due to greater production

Outgoing wood waste 5 trucks per week Increase due to greater wood waste production

Service, miscellaneous deliveries

3 vehicles per week Marginal increase in non-product deliveries

No relevant existing traffic data exists for Cove Hill Rd. However, the site is located in

an industrial precinct that includes multiple manufacturers, transport depots and a

waste transfer station within 1 km of the proposal site. It is considered that the

moderate increase in traffic movements from this proposal is immaterial in relation to

the existing traffic generated by the surrounding industrial operations on Cove Hill Rd.

Thus the associated traffic movements will not adversely impact the amenity of the



surrounding area.

4.9 Other off-site impacts

There are no other off-site impacts expected from the proposed site expansion.

4.10 Hazardous substances

There is currently no permanent fuel storage at the site, with the diesel forklifts being

refuelled from a 300 L fuel trailer, which is refuelled offsite approximately weekly. The

site redevelopment will include the installation of a 3000 L bunkered and self-bunded

diesel fuel storage container. This will comply with the requirements of AS 1940 The

storage and handling of flammable and combustible liquids. Fuel spill kits are

maintained at the designated forklift refuelling areas.

The site is connected to the natural gas pipeline, thus there is no requirement for gas

storage on site.

Lubricating oils and grease are required to maintain onsite equipment. The volumes

used are relatively minor and will be stored in an appropriately sized and bunded

hazardous goods cabinet to be installed in the new sawmill building. Oil spill kits will be

stored adjacent the hazardous goods cabinet.

In the event of a fuel or oil spill, the appropriate spill kit will be utilised to contain and

adsorb the spilled substance. The adsorbent material and any affected soil or wood

waste must be disposed of via licensed waste contractor.

Commitment 12 – Onsite diesel fuel storage will be limited to a 3000 L bunkered and

self-bunded fuel storage container, and spill kits will be available at the refuelling

location.

Commitment 13 – an appropriately sized and bunded hazardous goods cabinet will be

installed in the new sawmill building.

4.11 Site contamination (historical)

There is no known history of contamination at the site. The proposed expansion of site

operations will not generate any pollution that could contaminate soil and/or

groundwater at the site.



4.12 Heritage

4.12.1 European heritage

A search was undertaken of the Tasmanian Heritage Register and the Tasmanian

Historic Places Inventory for the site and general vicinity. There are no sites registered

on or in proximity to the site. Consequently, there is expected to be no impacts on

European heritage associated with the development.

4.12.2 Aboriginal heritage

An Aboriginal Heritage Assessment Report was commissioned to assess potential

impacts of the proposed site expansion on Aboriginal heritage in the area. This was

requested by the EPA due to the proximity of the site to the Jordan River, which is an

area of Aboriginal cultural importance, with the area containing many known Aboriginal

sites.

The report consists of three stages:

a background assessment including consultation with Aboriginal Heritage

Tasmania (AHT), a search of registered Aboriginal sites in the vicinity of the

project area and a literature review of relevant ethno-historic information;

a field assessment which included walking transects across the project site

encompassing an area of 1.5 ha; and

an assessment of the archaeological sensitivity and presentation of

management recommendations, and summary of the above in a report.

The search of registered Aboriginal sites identified 92 registered Aboriginal sites

located within an approximate 2km radius of the study area, however none were

located within or in the immediate vicinity of the project site. The nearest registered site

is located approximately 500m north east of the project site.

The field survey was undertaken on foot, with the field team walking 1.4 km of

transects, encompassing an area of approximately 1.5 ha. Surface visibility was

estimated at 30% due to exotic vegetation cover over the majority of the surface area.

There were no Aboriginal heritage sites recorded during the field assessment, and no

stone resources suitable for stone artefact manufacturing were identified.

On the basis of the negative survey findings, the absence of registered Aboriginal sites,

the low potential for undetected Aboriginal sites to be present and the fact that the

entire site is disturbed from previous agricultural activities, the proposal was assessed

as being of very low archaeological sensitivity. The report thus advises that there are

no Aboriginal heritage constrains or legal implements to the project proceeding. It

recommends that an Unanticipated Discovery Plan (UDP) is kept on site during



construction and personnel are made aware of their obligations under the Aboriginal

Heritage Act 1975 regarding unanticipated discoveries during construction activities.

Commitment 14 – An Unanticipated Discovery Plan will be implemented during the

project construction.

4.13 Sites of high public interest

There are no sites of high public interest in proximity to the proposal site.

4.14 Monitoring

It is proposed to undertake water quality sampling at the stormwater pond on a six

monthly basis, to enable the assessment of water quality compliance against the

expected compliance limits. Testing will measure pH, total suspended solids (TSS),

biological oxygen demand (BOD) and oil/grease. Drawing A111 Monitoring Locations

attached as Appendix 1 shows the location of this proposed monitoring location.

Commitment 15 – water quality sampling for pH, TSS, BOD and oil and grease will be

undertaken at the outlet of the stormwater pond every six months when flowing.

4.15 Rehabilitation

In the event of permanent closure of the site a Decommissioning and Rehabilitation

Plan will be developed and submitted to the EPA for approval.

The plan should include discussion and processes to:

Facilitate the orderly and safe removal of machinery and other equipment;

Establish sufficient vegetative ground cover to minimise dust and soil erosion;

and

Establish a monitoring regime to enable assessment of the effectiveness of the

plan.

Commitment 16 – A Decommissioning and Rehabilitation Plan will be developed and

submitted to the EPA for approval prior to the permanent closure of the site.



5 Part D – management commitments

No. Commitment

1 The site will be kept tidy by removing and disposing of uncontrolled wood waste from the roadways, non-log storage areas and undeveloped areas.

2 The biomass boiler will be designed, including a baghouse fabric filter system if required, to ensure it complies with an in-stack concentration limit of 100mg/m3 for particulate matter.

3 A sawdust capture and storage system will be installed on all additional saw milling equipment. This system will be serviced and maintained as per manufacturer’s recommendations, to ensure system continues to operating effectively.

4 Internal access roads will be appropriately maintained to minimise dust generation.

5 Visual monitoring of dust generation will be conducted by staff. If it is determined, through visual monitoring or public complaints, that dust from access roads is an nuisance to neighbours, then roads will be swept or watered to mitigate dust generation

6 Internal site traffic will be speed limited to 10 km/hr.

7 The log yard will be maintained by regular removal of loose wood waste, such that fugitive dust emissions are kept to a minimum.

8 Dust suppression in the log yard will be assisted by the use of water irrigation spray.

9 Ensure operation of milling equipment does not occur outside of the hours allowed by the existing site EPN.

10 Use material stockpiling (the long-term log storage yard) to afford further screening to the residences where practicable.

11 Conduct a noise survey of the operations once the new site is operating.

12 Onsite fuel storage will be limited to a 3000 L bunkered and self-bunded fuel storage container, and spill kits will be available at the refuelling location.

13 An appropriately sized and bunded hazardous goods cabinet will be installed in the new sawmill building.

14 An Unanticipated Discovery Plan will be implemented during the project construction.

15 Water quality sampling for pH, TSS, BOD and oil and grease will be undertaken at the outlet of the stormwater pond every six months when flowing.

16 A Decommissioning and Rehabilitation Plan will be developed and submitted to the EPA for approval prior to the permanent closure of the site.



6 Part E – Public and stakeholder consultation

Consultation has occurred with Brighton Council regarding the proposal. This has

included a site visit by planning staff and numerous correspondence regarding planning

aspects of the proposal.

Given the fact that the proposal site operates an existing industrial use at the site, and

is surrounded by industrial activities no public consultation was deemed necessary.



7 References

Dare, P. and Riley, S. 2003. Liquid condensate emissions from kilns drying radiate

pine. Proceedings 8th IUFRO International Wood Drying Conference 2003.

Forsyth, S.M. (compiler) 2002. Digital Geological Atlas 1:25 000 Scale Series. Sheet

5226. Richmond. Mineral Resources Tasmania.

Strata Geoscience and Environmental. 2018. Geotechnical Investigation 112 Cove Hill

Road Bridgewater.



Appendices

Appendix 1 - Site drawings:

A101A Location Plan A

A102 Site Plan

A103 Water Supply Plan

A104 Stormwater Detention Dam Upgrade

A105 Heavy Vehicle Access plan

A106 Crossover Detail

A107 typical Driveway detail

A108 Signage Details

A109 Air Emissions Plan

A110 Noise Emissions Plan

A111 Monitoring Locations Plan

Appendix 2 - Planning Application – Supporting Submission

Appendix 3 - Natural Values Report

Appendix 4 - Noise Assessment

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