saltas enterprises of tasmania, drum filter project

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Saltas Enterprises of Tasmania

Florentine Hatchery

Construction & Operation of Drum Filters

Environmental Effects Report

October 2018

SALTAS FLORENTINE HATCHERY, DRUM FILTER ENVIRONMENTAL EFFECTS REPORT

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Contents 1 PART A – Proponent Information .............................................................................................. 6

2 PART B - Proposal Description ................................................................................................... 7

2.1 Description of the proposed activity ............................................................................ 7

2.1.1 Description of proposed activity ...................................................................... 7

2.1.2 Summary of works ......................................................................................... 12

2.1.3 Commissioning and timeframes .................................................................... 13

2.1.4 Production rates ............................................................................................ 14

2.1.5 Solid organic waste and biosolid management plan ..................................... 15

2.2 Proposal area .............................................................................................................. 19

2.3 Map and site plan ....................................................................................................... 21

2.4 Rationale and alternatives .......................................................................................... 25

2.5 Planning information .................................................................................................. 27

2.6 Existing activity ........................................................................................................... 27

3 PART C - Potential Environmental Effects ................................................................................ 28

3.1 Flora and fauna ........................................................................................................... 28

3.2 Weeds and disease ..................................................................................................... 32

3.3 Aquatic environment and wastewater ....................................................................... 32

3.3.1 Aquatic Environment ..................................................................................... 33

3.3.2 Wastewater.................................................................................................... 39

3.3.3 Alternative options for Wastewater Management ....................................... 41

3.3.4 Therapeutic treatments ................................................................................. 42

3.3.5 Stormwater, sediment and runoff control .................................................... 42

3.3.6 De-sludging .................................................................................................... 43

3.4 Significant areas .......................................................................................................... 43

3.5 Air emissions ............................................................................................................... 43

3.5.1 Odour Management ...................................................................................... 44

3.5.2 Dust ................................................................................................................ 44

3.6 Solid wastes ................................................................................................................ 45

3.7 Noise emissions .......................................................................................................... 45

3.8 Transport impacts ....................................................................................................... 47


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3.9 Other off-site impacts ................................................................................................. 48

3.10 Hazardous substances ................................................................................................ 48

3.11 Site contamination (historical) .................................................................................... 49

3.12 Heritage ...................................................................................................................... 49

3.13 Sites of high public interest ........................................................................................ 49

3.14 Monitoring and review ............................................................................................... 49

3.15 Rehabilitation .............................................................................................................. 52

4 PART D - Management Commitments ..................................................................................... 53

5 PART E - Public and Stakeholder Consultation ........................................................................ 55

6 References ............................................................................................................................... 56


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List of Figures

Figure 1 Process flow arrangement for current operations at Florentine Hatchery .............................. 8

Figure 2 Process flow arrangement for Florentine Hatchery post installation of drum filter (green

boxes). ..................................................................................................................................................... 9

Figure 3 Illustration of a Hydrotech drum filter .................................................................................... 10

Figure 4 Schematic of Florentine Hatchery drum chamber isometric ................................................. 11

Figure 5 Illustrations of the sludge clarifier (a); internal schematic of sludge clarifier (b) ................... 16

Figure 6 Flow diagram of waste removal process with the proposed drum filter ............................... 18

Figure 7 Location map of Florentine Hatchery and surrounding area with intake and discharge

locations (red and yellow stars) 22

Figure 8 Schematic of the current site arrangement at Florentine Hatchery ...................................... 23

Figure 9 Schematic of the Florentine Hatchery settlement pond with the proposed drum filter

location and surrounding existing and proposed infrastructure .......................................................... 24

Figure 10 Location of observations of Wedge-tailed Eagles nests and modelled Wedge-tailed Eagle

habitat in the vicinity of the Florentine Hatchery. ................................................................................ 31

Figure 11 Coordinates and diagram of water quality sampling locations for Florentine Hatchery ..... 51


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List of Table

Table 1 Drum filter specifications ......................................................................................................... 10

Table 2 Expected excavation volumes .................................................................................................. 13

Table 3 Biomass levels and maximum feed rates at Florentine Hatchery ............................................ 14

Table 4 Typical daily water intake in the RAS and flowthrough systems at the Florentine Hatchery .. 14

Table 5 Monthly average of river flow discharge from Hydro Tas Station 40.1 on Florentine River ... 19

Table 6 Monthly average rainfall and temperatures for Florentine area ............................................. 20

Table 7 Data sources and approaches to aquatic biodiversity-focused environmental impact

assessment for Tassal and SALTAS freshwater hatcheries. TSPA = Tasmanian Species Protection Act

(1995); EPBC = Environment Protection and Biodiversity Conservation Act (1999) ............................ 29

Table 8 Details of observations of nearest Wedge-tailed Eagle nests to the Florentine Hatchery in the

Tasmanian Natural Values Atlas. .......................................................................................................... 31

Table 9 List of upstream sampling events from 2015, 2016, 2017 and 2018. Note that not all

parameters were sampled and/or analysed during each sampling event. .......................................... 34

Table 10 Number of data points for each parameter by year and season. Parameter 1 refers to

parameters measured in the Florentine Hatchery sampling program. Parameter 2 refers to the

equivalent label in Water Quality Default Guideline Values for the Upper Derwent. ......................... 35

Table 11 Annual default water quality guideline values for the Upper Derwent (DER) and

(preliminary) derived water quality guideline values for Florentine Hatchery (FLO). .......................... 37

Table 12 Seasonal default water quality guideline values for the Upper Derwent (DER) and

preliminary derived water quality guideline values for Florentine Hatchery (FLO). ............................ 38

Table 13 Median, 90th percentile and maximum parameter values for water samples taken from the

settlement pond and downstream of Florentine Hatchery. ................................................................. 40

Table 14 Interim effluent quality limits for Florentine Hatchery .......................................................... 41

Table 15 Chemical agents used at Tassal and Saltas hatchery facilities (data source: Tassal and

SALTAS) ................................................................................................................................................. 42

Table 16 Water quality parameters measured for monitoring program ............................................. 50

Table 17 Commitments table ................................................................................................................ 53


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1 PART A – Proponent Information

Saltas enterprises of Tasmania Pty Ltd (SALTAS) is an industry owned hatchery operation which

produces salmon eggs, fry and smolt. SALTAS shareholders comprise of Tassal Operations Pty Ltd,

Huon Aquaculture Company Pty Ltd, Petuna Aquaculture Pty Ltd, Alstergren Aquaculture and the

Tasmanian Government. The registered address of Saltas is:

Salmon Enterprises of Tasmania Pty Ltd

289 Wayatinah Road

Wayatinah Tasmania 7140

ABN 38 106 324 127

The contact person for this project is:

Craig Selkirk – Senior Manager (Freshwater) Email: [email protected] Ph: 0407 318 068

This document has been prepared in consultation with suitably qualified consultants and the Tassal

Environment and Engineering Departments.


2 PART B - Proposal Description

2.1 Description of the proposed activity

• Description of the proposed activity, including method of operation and the main items of equipment.

• Provide details on collection, storage and use of influent water, including coordinates for the location

of the water off-take, quantity of influent water, use of the water and any contingency water sources.

• Summary of works to be undertaken to prepare the site for installation of the drum filter and

associated infrastructure.

• Timeframe over which each component of the activity is proposed to occur.

• Solid organic waste management including expected volumes, disposal arrangements with

contractual arrangements with third party service providers.

• Specify production capacity, production rates and describe any seasonal variations.

2.1.1 Description of proposed activity

SALTAS proposes to install and operate drum filters as part of the treatment system of the hatchery’s

effluent water. The drum filter is deemed the most feasible system to remove solid particles and

reduce the organic and nutrient concentrations of the effluent being released to the receiving

environment (the Florentine River).

Currently, Florentine Hatchery consists of an incubation and fry system and a broodstock and on-

growing system. Water to supply these systems comes from the Florentine River (Eastings 459436,

Northings 5301067).

For the purposes of this proposal it is assumed that daily flow through the hatchery is equivalent to

600-900 litres/second (approximately 20,075,000 to 28,470,000 m3 per year) with an approximately

equal intake contribution (50:50) from the river and the lake pumps. These values are assumed on

hatchery tanks and channels being at maximum holding capacity. Based on current operations at the

hatchery these maximum flow rates are unlikely to be reached. These flow rates are consistent with

the design specification for the drum filters at maximum flow loading whilst also maintaining

redundancy capabilities.

Currently all hatchery through flows and waste streams are directed to the existing settlement pond,

situated at a lower elevation than the rest of the hatchery infrastructure. The hatchery water flows to

the settlement pond under gravity via a network of buried pipes, pits and channels. All flows are

combined to enter the settlement pond via one large diameter pipe (outfall pipe). Figure 1 illustrates

the current arrangement of the process flow at the hatchery.


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Figure 1 Process flow arrangement for current operations at Florentine Hatchery

The proposed drum filters would remove solid particles from the hatchery outflow by passing the

effluent stream through a micron filter mesh. A fine mesh filter with aperture size of 80 µm would

remove solid particles from the effluent flow. The filter mesh is attached to a rotating mechanical

drum which rotates at a predefined speed and interval to maximise solids capture.

As the effluent passes through the rotating drum filter mesh, solid particles (>80 µm) build up on the

filter panels and begin to form a sludge cake layer. Formation of the sludge layer on the filter mesh

improves the capture rate of the filter mechanism until the sludge thickens to a point of blockage.

As the drum filter continues to rotate, the sludge cake passes an elevated backwash spray bar,

backwashing the sludge into an internal trough. Plumbing directs the backwash sludge away from the

drum to the transfer pump.

The drum filter is supplied on a stainless steel frame, with control panel and backwash pump included.

The frame allows the drum filter to be submersed in the effluent stream. High-density polyethylene

(HDPE) weirs direct the flow to the filter inlet.


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The proposed drum filter arrangement specifies two drum filters be installed side by side, each

filtering 50% of the total flow. Both drum filters have been designed to cope with 100% flow rate to

accommodate for any cases of a drum filter malfunction or when maintenance is required. Any

scheduled maintenance would occur outside of peak biomass periods at the hatchery.

The drum filters would be housed in a concrete structure that enables the hatchery outflow to be

directed to the drum filter inlets. Predominantly, the concrete structure would be a pre-cast concrete

which is lifted into position using a mobile crane. Elements of the structure such as the base and stitch

joints shall be cast in-situ concrete.

The drum filter structure would be situated on the hatchery outfall pipe, in the hatchery settlement

pond. Figure 2 illustrates the updated process flow arrangement post drum filter installation

(proposed drum filters are illustrated by the green boxes).

Figure 2 Process flow arrangement for Florentine Hatchery post installation of drum filter (green boxes).


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Table 1 and Figures 3 and 4 provide a description and schematics of the proposed drum filter and

model specifications.

Table 1 Drum filter specifications

Drum Filter Specifications

Make/Model Hydrotech HDF1606-2S – 316SS

Micron filtration 80um

Flowrate Capacity (2 drum filters in parallel)

588L/s (1,176L/s combined)

Steel Frame 316SS

Backwash Pump MTR5-24/16

Figure 3 Illustration of a Hydrotech drum filter


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Figure 4 Schematic of Florentine Hatchery drum chamber isometric


2.1.2 Summary of works

To prepare the site for installation of the proposed drum filters a work zone perimeter would be

established around the existing settlement pond to control access to the works area (the work zone

perimeter is illustrated by the red hatched areas in Figure 9). Civil preparation work would be

undertaken in the settlement pond to enable footings to be installed and the relative construction

levels to be completed. No native vegetation currently exists within the construction zone area and

clearing of any native vegetation outside the construction zone will not occur without express

permission of the Site Manager.

Due to the nature of the flow-through hatchery operations, outfall water through the discharge pipe

cannot be stopped without stopping flow through the fish tanks. However, undertaking construction

works in the settlement pond while outflow continues creates a workplace health and safety risk and

is not feasible from a constructability perspective. Therefore, it is proposed to manage the settlement

pond water volume and construction works zone via two methods:

• lower the settlement pond water volume by opening the weir bypass valve at the settlement

pond outlet; and

• install a temporary dam wall around the construction work zone (sand bag or approved

equivalent).

A submersible slurry pump would be utilised to mitigate pond/ground water in the works zone. The

pump outfall would be directed to a sedimentation trap established as part of the works. Suitable

sediment controls will be implemented to allow sediment to be contained (such as sediment fencing,

earth bunds, filter socks, etc.) and run off to be returned to the settlement pond.

The existing settlement pond is not considered to function as a sufficient water treatment plant

therefore, the effluent water following into the Florentine River during the construction phase of the

project is not expected to result in increased inputs of organic nutrients. A further discussion of this

can be found in section 2.4 of this document.

During the construction period while pond levels are lowered, de-sludging would be undertaken in

line with draft Tassal Freshwater Hatcheries Wastewater Solids Management Plan.

Within the work zone a sump would collect residual ground water and sump pump would remove the

water to a sediment trap established adjacent to the settlement pond. Silt traps, hay bales or approved

equivalent would be used to construct the silt trap.

Diversion of the hatchery water flow is not required as the work would be undertaken adjacent to the

settlement pond.

Civil preparation work would include:

• establishing a temporary dam;

• excavation to formation levels; and


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• ground water management.

Due to the proposed location of the drum filter structure occurring within the settlement pond, little

excavation spoil would be generated. Any removed material would be stockpiled on site and will be

maintained to industry best practice through the use of sediment fences, earth bunds and appropriate

soil stabilisation techniques. This includes re-vegetating stockpiles where necessary.

Expected excavation volumes are shown Table 2. No excavated material would be removed from the

site, as it will be reused and compacted as trench backfill where possible.

Table 2 Expected excavation volumes

Florentine Civil Volumes

Excavation Cut 155m3

Excavation Fill 70m3

Commissioning will be undertaken in a multi-stage approach. During project implementation,

equipment will be inspected for damage and completeness. Once approved, and mounting

arrangements are complete, equipment will be installed to specifications. All auxiliary systems,

plumbing and electrical would be attached in line with the appropriate project sequencing. Equipment

will only be energised once all systems installations have been completed and signed off.

Once the civil/concrete works are complete, mechanical install would begin. To commence

commissioning of the drum filter system, the plumbing and sludge system must also be completely

installed. When the drum filter is commissioned, the system will generate sludge from the outset,

therefore the full process flow would be completely installed before any operations were ‘switched

on’.

2.1.3 Commissioning and timeframes

The construction period for the Principal contractor/Civil works contract is anticipated to take

approximately 15 weeks from contract award, based on the contractor supplied schedules.

Mechanical installation is expected to take approximately three weeks.

Commissioning is expected to take two weeks with the operational observation period expected to

take six weeks. This six week observation period will allow for monitoring of system performance to

make any necessary adjustments to improve efficiency/effectiveness, and also to identify how the

system handles unknowns such as river debris or weeds that may hinder operation, as well as make

adjustments in process flow.

The total timeframe of construction to end of commissioning period is expected to be a five month

period commencing in December 2018 or January 2019 pending approval.

Once fully operational, the drum filter is expected to operate on 24 hour/year round basis.


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2.1.4 Production rates

Table 3 shows the total biomass and maximum feed rates at the hatchery for each month of the year

2017. Maximum figures can fluctuate depending on the year.

Table 3 Biomass levels and maximum feed rates at Florentine Hatchery

Month Flow-through biomass (tonnes)

Flow- through feed rates (tonnes)

January 47 26.2

February 61.3 21.3

March 87.7 31.5

April 87.8 37.6

May 60.2 20.4

June 74.3 13.7

July 24.4 11.1

August 36.4 11.2

September 15 5.6

October 38 13.5

November 9 6.6

December 19.4 12.2

The associated volumes of water passing through the RAS and flowthrough systems at the hatchery

are presented in Table 4.

Table 4 Typical daily water intake in the RAS and flowthrough systems at the Florentine Hatchery

Daily Water Intake (kL)

Month Flow Through Recirculation TOTAL

January 48000 42.8 48042.8

February 59760 42.8 59802.8

March 59760 42.8 59802.8

April 59760 51.6 59811.6

May 48000 8.8 48008.8

June 42000 8.8 42008.8

July 53760 22 53782

August 30240 22 30262

September 30240 23.7 30263.7

October 13440 34.4 13474.4

November 25200 34.4 25234.4

December 33600 34.4 33634.4


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2.1.5 Solid organic waste and biosolid management plan

The sludge stream from the proposed drum filter configuration would be pumped to the proposed

sludge dewatering plant via the sludge transfer pump. The sludge dewatering plant will consist of a

plate clarifier and a series of agitated storage tanks and will be installed adjacent to the drum filter

(within 30m radius).

A single buried pipe would deliver the sludge stream to a plate clarifier (Figure 5a) that acts as a pre-

treatment thickener. The sludge stream would have a high water/low solids content at this stage of

the process flow (<1% solids).

The clarifier uses specific gravity and low velocity to passively settle out solid particulate from the

main flow stream, concentrating the sludge to a higher percentage of solid content (estimated 5 to

10%). The clarified main flow stream is returned to the drum filter inlet. The concentrated sludge is

pumped via a dedicated sludge pump (Figure 5b). It is considered that returning the clarified main

flow stream back into the drum filter inlet would not result in high concentrations of dissolved

nutrients, however if exceedances of the interim effluent quality limits (see Table 14) occur then

SALTAS will conduct analysis of the clarifier overflow and if necessary will implement a management

control to separate this water and divert to a storage tank for removal from site or provide treatment

of the water before it re-enters the drum filter.

As the sludge is removed from the main flow stream, it falls into the bottom of the clarifier and forms

a sludge layer in the hopper below (integrated in the clarifier housing). This sludge layer is evacuated

from the hopper and forms a new concentrated sludge stream which will be pumped to

aerated/agitated storage tanks. The storage tanks will fill gradually and when full shall be pumped out

by an approved sludge removal contractor.

The overflow from the storage tanks will be plumbed to a buffer tank which will capture any overflow.

The buffer tank will also be pumped out as required.

Figure 6 illustrates the waste removal process a detailed schematic of the sludge treatment plant can

be found in Appendix A.


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Figure 5 Illustrations of the sludge clarifier (a); internal schematic of sludge clarifier (b)

The total solid organic waste captured by the drum filter is based on the solids leaving the hatchery,

which is dependent on biomass carrying capacity and feeding rates. The estimated volume of solid

waste generated in the effluent at Wayatinah Hatchery is 149 kg/day. This equates to 4.5 dry

tonnes/month or 24.8 wet tonnes/month. Note: dry weight refers to the dry weight of solids, without

water content. The wet weight refers to the solids including the wet content. After the dewatering

process, the dry solids content is 18%, meaning 82% is water.

Based on a pump frequency of 10 L/sec for 20 seconds every hour (between the clarifier to tank) it is

estimated 4.8 kL/day of sludge will be transferred to the storage tank. Removal of the sludge from the

storage tank would occur every four days, with a second 22 kL storage tank acting as a buffer for any

overflow. The amount of sludge generated will not change during peak biomass periods, it will only

result in a more concentrated stream of sludge.

The storage tanks will be located on a concrete hardstand and will be removed by licenced waste

removal contractor (e.g. Spectran Group – controlled waste handler CWTEMP224TA/1) and taken to

an approved waste facility that is licenced to take organic waste of these volumes (e.g. Brightside

Composting EPN 8894/1) where it will be land spread or composted.

The removal of the solid organic waste would be managed under an approved biosolids management

plan for the hatchery. The draft Tassal Freshwater Hatcheries Wastewater Solids Management Plan is

currently being developed in accordance with the Tasmanian Biosoilds Reuse Guidelines 1999 and

encompasses all Tassal hatcheries and the Saltas hatcheries.

Initial screening of wastewater solids was carried out in 2018 for Tassal’s Rookwood, Russell Falls and

Karanja hatcheries to determine the contaminant grade of biosolids. Results indicated that all test

parameters were within accepted thresholds defined in Tasmanian Biosolids Reuse Guidelines 1999.

It is expected that screening results of the biosolids produced by the operation of the drum filter will

a b


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be similar. Biosolids monitoring will be undertaken in accordance with the draft Tassal Freshwater

Hatcheries Wastewater Solids Management Plan.

Biosecurity

Management of biosecurity is vitally important to hatchery operations to safeguard the health of the

fish is maintained. A number of existing internal policies are implemented at SALTAS Wayatinah

Hatchery to ensure biosecurity is managed effectively including:

• ENV-001 Waste Management Policy

• ENV-002 Biosolids Management Policy

• WHS-022 Biosecurity Visitor Policy

• WHS-023 Biosecurity Staff Policy

Furthermore, the biosecurity management of the sludge waste generated from the drum filter will be

managed in accordance with the draft Tassal Freshwater Hatcheries Wastewater Solids Management

Plan. The biosecurity controls requirement outlined in the Plan are listed below:

• The sludge storage tank and buffer tank are to be maintained in good condition (i.e. no

leakages or cracks) and is to be inspected on a weekly basis;

• Removal of the sludge occurs every four days to prevent the tank overflowing (to be managed

under an ongoing contractual arrangement with waste transporter);

• The sludge storage tank and buffer tank are enclosed;

• Transport of sludge will be in an enclosed tanker;

• SALTAS will ensure that the waste transport contractor implements a truck washdown

procedure for all vehicles prior to entering the hatchery site; and

• SALTAS will ensure that the waste transport contractor has an adequate spill prevention and

control procedure in place.


Figure 6 Flow diagram of waste removal process with the proposed drum filter

Buffer tank


2.2 Proposal area

• General description of the physical environment surrounding the proposed activity – topography,

vegetation, wetlands, watercourses, buildings.

• Description of receiving environment for effluent discharge; identify Protected Environmental Values,

current downstream uses, general hydrology, seasonal flows.

• Description of local climate – rainfall, temperatures.

• Current and historical use of the site.

• Land tenure, land zoning of the site and surrounding land.

• Description of surrounding land use, including location of nearest residents and other sensitive uses.

• Description of soils and underlying rock types.

Florentine Hatchery (PID 3386594) is located at 675 Florentine Road: E459991, N5301356 and is

owned by Forestry Tasmania. Under the Central Highlands Interim Planning Scheme 2015 the hatchery

site is located on land zoned as 26 – Rural Resource.

The Florentine Rive is the largest tributary of the lower Derwent River System. It contributes 11% of

the total flow of the Derwent at Lake Meadowbank, or 30% of the Derwent’s flow that is derived below

Tarraleah and Tungatinah. Historic monitoring shows naturally elevated conductivities in the

Florentine River, with values up to 400 µS/cm. Elevated conductivity, pH and nitrate values have been

attributed to the presence of limestone in the Florentine River Catchment. The catchment is primarily

under wood production. From the Florentine Hatchery, the Florentine River flows into the Derwent

River (approx. 1 km downstream) which is dammed to formed Lake Catagunya (Davies, 2015).

Table 5 shows the monthly average of river flow discharge from Station 40.1 (Lat: -42.44; Long: 146.52)

on the Florentine River below the Florentine Hatchery since Jan-17. The data indicates that highest

flow is generally during the winter to spring months with lowest flow in summer though autumn.

Table 5 Monthly average of river flow discharge from Hydro Tas Station 40.1 on Florentine River

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Mean flow discharge

2017*

(litres/second)

3410 3809 1850 2164 4922 7324 12595 19823 29582 14400 4787 6736

Mean flow discharge

2018*

(litres/second)

2362 3428 4448 7543 11600 12138 27281 27768 9763 - - -

*Hydro Tasmania watercourse discharge station (#40.1 Florentine River – A/B Derwent River)

Table 6 shows the monthly average rainfall and temperatures for the area. The prevailing wind

direction at Florentine is westerly.


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Table 6 Monthly average rainfall and temperatures for Florentine area

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual

Mean Rainfall (mm)*

58.1 50.7 64.5 78.9 116.2 108.1 137.6 169.0 158.0 132.0 83.4 88.8 1292.6

Mean Temperature

(°C)** 18.9 18.8 16.6 13.1 10.0 7.8 7.0 8.0 10.2 12.6 14.7 16.7 12.9

*BOM Wayatinah (Saltas) station **BOM Butlers Gorge station

There are no formal or informal reserves associated with aquatic habitats within the vicinity of the

Florentine Hatchery, or within 10+ km upstream or downstream of the outfall. The Forest Practices

Code applies to forestry operations in the catchment immediately upstream of the hatchery, but does

not constitute a formal reserve system. All land associated with the Florentine Hatchery and the river

and riparian zones upstream and downstream of it fall within a Permanent Timber Production Zone

declared under the Tasmanian Forest Management Act.

Overall, there are no aquatic habitats that are reserved. Some aspects of riparian land upstream of

the Florentine Hatchery is either formally reserved or subject to operational or informal reservation

constraints under production forest operations, none of this reservation is predicated on or enacted

in relation to specific aquatic environmental values, nor places obligations or requirements on SALTAS

in relation to aquatic impact management (Davies, 2017).

The hatchery was constructed in 1987 by SALTAS. Prior to construction the land was managed by

Forestry Tasmania. The nearest residences are situated in the township of Wayatinah approximately

6 km north of the hatchery. Wayatinah is a small township with a population of approximately 20-30

permanent residents. There is no line of site to Wayatinah from the hatchery.

Vegetation surrounding the hatchery is classified as Eucalyptus obliqua forest with broad leaf shrubs

(TASVEG 3.0). There are no threatened vegetation communities in the area. The underlying rock type

at the site is dolerite (tholeiitic) with locally developed granophyre (LISTMap 2018). There area has

not been identified as having an acid sulphate soils risk or being susceptible to erosion.

The Protected Environmental Values (PEVs) that have been identified downstream of the Florentine

Hatchery at Lake Catagunya include:

• Ecosystem protection

• Recreational water quality (primary and secondary) and aesthetics

The identification of these values means that, at minimum, the water quality management strategies

of the hatchery should seek to provide water of a physical and chemical nature to support a healthy,

but modified aquatic ecosystem from which edible fish may be harvested and which will allow people

to safely engage in primary contact recreational activities such as swimming (at specific sites) and

secondary contact recreational activities such as paddling or fishing in aesthetically pleasing waters


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(DRC 2003). Refer to section 3.3.1 for discussion on the water quality management strategies of

Florentine Hatchery and impacts on the PEVs.

2.3 Map and site plan

• General location map (e.g. 1:25,000 scale).

• Site plan showing boundary of the land and footprint (operational area), position of existing

structures and proposed drum filter, native vegetation, watercourses, potential locations for effluent

disposal, effluent conduits, sources of noise and odour emissions, stormwater collection systems,

drainage control and significant earthworks.

Figure 7 illustrates the boundaries of the Florentine Hatchery and the surrounding environment

including watercourses (Florentine and Derwent rivers and Lake Catagunya) and roads. The proposed

drum filter will be installed within the existing boundaries of the Florentine Hatchery site. The nearest

residents are located within the Wayatinah village more than 7 km from the hatchery.

Figure 8 is a schematic of the current site arrangement including buildings (including RAS), broodstock

and on-growing fish tanks, and settlement pond.

Figure 9 is a schematic of the Florentine Hatchery settlement pond with the proposed drum filter

location and nearest associated existing and proposed infrastructure. Refer to Appendix B for further

detailed schematics.


Figure 7 Location map of Florentine Hatchery and surrounding area with intake and discharge locations (red and yellow stars)

N

River intake pump

459427 E 5301052 N

Effluent discharge point

4601885 E 5301333 N

Florentine River

Derwent River

Florentine Road

SALTAS Florentine Hatchery


Figure 8 Schematic of the current site arrangement at Florentine Hatchery


Figure 9 Schematic of the Florentine Hatchery settlement pond with the proposed drum filter location and surrounding existing and proposed infrastructure


2.4 Rationale and alternatives

• Describe the rationale for the proposal. Explain benefits and disadvantages of alternative options that

have been considered.

• Justification for any proposed diversion of effluent to the receiving environment during construction

phase.

Effluent management at the Florentine Hatchery has consisted of discharge of combined aquatic

waste from all farm areas through a single settling pond facility and discharge point to the receiving

watercourse.

As stated in section 2.1.4, the current settlement pond is considered inadequate to effectively treat

hatchery effluent water through the settling of suspended solids. Therefore, the drum filter is

considered necessary to improve effluent quality released from the hatchery into the receiving

environment of the Florentine River.

Flow through hatcheries take freshwater from the natural water course via an upstream weir, or

similar, and direct the water through the hatchery fish tanks, returning water back to the watercourse.

For Florentine Hatchery water comes from the Florentine River with discharge directed back into the

Florentine River. Water flow into the hatchery equals water flow out of the hatchery. Any treatment

methodology implemented to improve nutrient loading at the outflow (end-of-pipe) must be

adequately sized to treat the high volumetric flowrate (hydraulic loading) of the hatchery at peak

loading.

Preliminary scoping discussions at project concept state identified a number of possible alternate

treatment methodologies. These options included:

• Increased desludging

• Increased retention in existing settlement pond

• Wetlands

• Bio-filtration

• Drum filter

Each option was considered in terms of hydraulic loading, required footprint and the layout of the

existing site, as well as capital investment, power consumption and additional staffing requirements.

The following summary describes each option assessed against site constraints and considered in

terms of the existing operation and expected environmental performance.

Increased desludging

Desludging is the manual removal of settled sludge from the pond basin by pump or excavation. This

is a maintenance requirement for settlement ponds and is considered to improve water quality by

limiting the breakdown of settled sludge.


26

Desludging is common practice for settlement ponds and the settlement pond at Florentine Hatchery

has desludging factored into the maintenance program. However, this practice alone is not considered

adequate enough to remove solids from hatchery effluent.

Increased retention in existing settlement pond

To increase retention time to improve settling of solids, the settlement pond at the hatchery would

need to be increased in size. The settlement pond has a current volume capacity of 2,150 m3 with a

retention time of 40-60 minutes. The industry standard for retention time in a settlement pond is

considered to be at least one hour at 900 L/s.

To increase the pond to an adequate size to allow for more than one hour retention time is not

possible in the ponds current location because of:

• the adjacent Florentine River and risk of flooding;

• the limited space available to expand the pond and access road around the perimeter of the

pond; and

• the elevation requirement to make it work.

Additionally, settlement ponds are deemed ineffective as the primary method of treatment due to

their inefficiency, particle breakdown within the pond, and anaerobic microbial reaction of the sludge

accumulated in the pond basin.

Wetland

Typically, wetlands use a catchment basin designed for nominally five-day retention time combined

within selected plant life population to filter nutrients from the flow stream. Due to the topography

of the surrounding area, the large footprint required and the availability of land, this option was not

considered viable for Florentine Hatchery.

Bio-filtration

Bio-filtration uses multi-stage filtration chambers, micron screens, sludge pumping and bio media to

improve water quality parameters. Suspended solids are removed using micron filtration and

dissolved nutrients such as ammonia are removed by microbial reaction.

Project and operational considerations for this option included:

• high power consumption;

• significant infrastructure upgrade;

• multiple pumping stations;

• deep excavation; and

• multiple auxiliary support systems.

Based on Tassal’s recent Rookwood Road Hatchery project, the estimated concrete structure required

to treat 900 L/s flow rate would be 20m x 20m x 4.5m deep.


27

As part of implementing a biofilter to improve dissolved nutrient loading, the solids load would need

to be reduced using a micron filter. Estimated capital required to implement a micron screen system

with a bio-filtration system sized for a hydraulic load of 900 L/s exceeds $4 million. Therefore, from

both a financial and size perspective, this option is not considered viable.

Drum filter

A drum filter removes suspended organics in the effluent stream using micron filtrations. Captured

particulate matters is generally dewatered using a sludge plant or stored in bulk volumes prior to being

removed from site. Suspended particles in flow-through hatcheries contain nutrients such as

phosphorus and nitrogen, and BOD, bound into the particles. As the particles flow downstream,

turbulence encourages the soft particles to break down releasing the bound nutrients and allowing

them to dissolve in the water stream.

Micron filtration gently removes the particulate matter from the water stream before it breaks down,

thus reducing the nutrient loading. Drum filters are widely used in a variety of industries for solid

particle removal. By design, drum filters, have the capacity to filter high volumetric flow rates

efficiently and with low maintenance costs. Substantial capital investment is required for

implementing adequate permanent infrastructure to manage water flow and handle sludge

generation.

Based on the flow rates and solid loading that currently exists for the Florentine Hatchery, the drum

filter is considered the most viable and effective option for improving effluent water.

2.5 Planning information

• Identify components of the proposal to which the planning application relates.

• Description of the status of the activity under LUPAA 1993 and local Council’s Planning Scheme.

In December 2018, Schedule 2(4) Environmental Management and Pollution Control Act 1994

(EMPCA) was amended to include finfish farming as level 2 activity. On 4 January 2018, Saltas was

notified by the Director of the EPA that all fish farms that hold an existing authorisation are taken to

have applied for an environmental license under the Land Use Planning and Approvals Act 1993

(LUPAA) and that any proposed modification of an existing fish farm, will be environmentally assessed

under EMPCA.

2.6 Existing activity

• Details of any current regulatory approvals (permit, licence, EPN, etc.) relating to the existing activity.

• Provide summary of existing environmental monitoring results, public complaints and breaches of

conditions of current regulatory approvals.

• Details of any contraventions of environmental law (if any).


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Florentine Hatchery operates under Inland Fisheries Services (IFS) Finfish Licence No. 40, issued by the

IFS under section 40 of the Inland Fisheries Act 1995 (Appendix C) and Environmental Licence No.

9840/1, issued under the Environmental Management and Pollution Control Act 1994.

SALTAS has no records of public complaints relating to operations at Florentine Hatchery nor any

breaches of regulatory conditions as listed in the documents described above.

All environmental monitoring is detailed in section 3.14.

3 PART C - Potential Environmental Effects

3.1 Flora and fauna

• Are there any known occurrences of species of conservation significance, threatened fauna or flora

species or threatened vegetation communities on or near the site? If so, or if the site has potential

habitat for any such species, a detailed survey is likely to be required and the results should be

presented in the report.

• Provide a statement as to whether the proposals may impact upon matters of national environmental

significance or upon Commonwealth land.

In 2017, to address indicators within the Aquaculture Stewardship Council (ASC) Salmon standard,

Saltas conducted an aquatic Biodiversity Focused Environmental Impact Assessment (BFEIA) for its

facilities discharging to freshwater receiving environments. The assessment included a description of

habitats and species that could be reasonable impacted by the farm, incorporating the identification

of proximity to critical, sensitive or protected habitats and species and any potential impacts the

farm may have on biodiversity (see Table 7).

SALTAS FLORENTINE HATCHERY, DRUM FILTER

ENVIRONMENTAL EFFECTS REPORT Table 7 Data sources and approaches to aquatic biodiversity-focused environmental impact assessment for Tassal and SALTAS freshwater hatcheries. TSPA = Tasmanian Species Protection Act (1995); EPBC = Environment Protection and Biodiversity Conservation Act (1999)

Assessment Component Data source(s) BFEIA Approach

Listed species Species listed under the TSPA and EPBC; the Tasmanian Natural Values Atlas; the CFEV database (Conservation of Freshwater Ecosystem Values) database

Review data to identify candidate species and locations. List relevant species and characterise relative risks.

Sensitive non-threatened species Inland Fisheries Service fishery management plans and fishery performance data; CFEV database.

Review sources and identify: Priority species – CFEV; commercial fishery species – eels; recreational fishery species - brown trout and bream. Assess relative significance of farm receiving waters for sensitive species within local and state context. List relevant species and characterise relative risks.

High conservation value aquatic habitats

CFEV database Identify all CFEV High rated ICV (Integrated Conservation Value) stream reaches and lakes potentially affected by farm operations and discharges (within 5-10 km downstream). List relevant habitats and characterise relative risks.

Identification and description of potential impacts

Tassal/Saltas data on water quality, farm disease status, antibiotic and chemical use and discharge; WIST (Water Information System Tasmania) database; Hydro Tasmania water quality data.

List potential causes/risk factors of environmental aquatic impact. Scan data sources for potential nutrient, antibiotic, toxicant, xenobiotic chemical and disease levels and impacts on receiving rivers, nutrient status of lakes. Rate against ANZECC (2000) water quality guidelines where relevant. List and characterise risks from most relevant potential causes/risk factors.

Current and future programs and strategies to eliminate or minimise identified impacts

Documentation on Tassal/Saltas procedures and risk assessments

Summarise current Tassal/Saltas procedures and assessments. Discuss strategies with Tassal/Saltas personnel. Collate information and summarise key features and needs of programs and strategies.

Monitoring of outcomes of above programs and strategies

Tassal/Saltas monitoring program plans and reports

Review current Tassal/Saltas monitoring programs. Collate information and summarise key features and needs for monitoring.


ENVIRONMENTAL EFFECTS REPORT

A desktop assessment of the area surrounding the Florentine Hatchery was conducted using LISTMap

(2018). No listed flora or fauna species were identified to occur within the immediate proximity of the

Florentine Hatchery. However, the habitat surrounding the hatchery is identified as highly suitable

nesting habitat for the Wedge-tailed Eagle.

The Tasmanian Wedge-tailed Eagle is listed as endangered under the Environment Protection and

Biodiversity Conservation Act 1999 and the Threatened Species Protection Act 1995. The major threat

to this species is the loss of nesting habitat and disturbance of nesting birds (Threatened Species

Section 2006). Tasmanian conservation agencies apply a basic policy of not having heavy disturbance

within 500 m, or 1 km if within line-of-sight, of nests of the Wedge-tailed Eagle during breading season

(FPA 2013). These distance-based guidelines were developed to control the impacts of forestry

operations (which involve both extensive habitat loss and heavy, sometimes prolonged disturbance)

on breeding eagles and have been successful in minimizing the effects of forestry disturbance on

breeding birds (FPA 2013).

A search of the Tasmanian Natural Values Atlas for observations of the Wedge-tailed Eagle within the

vicinity of the Florentine Hatchery was conducted with 1 km buffers drawn around each nest to assess

if the hatchery fell within the threshold distance applied by Tasmanian management agencies (Figure

10). There were no known Wedge-tailed Eagle nests identified within 1 km of the Florentine Hatchery.

The nearest site was approximately 1.5-1.7 km from the hatchery. This nesting site has been observed

eight times between 2003 and 2015 but notes state that the nest is not active (Table 8).


31

Figure 10 Location of observations of Wedge-tailed Eagles nests and modelled Wedge-tailed Eagle habitat in the vicinity of the Florentine Hatchery.

Table 8 Details of observations of nearest Wedge-tailed Eagle nests to the Florentine Hatchery in the Tasmanian Natural Values Atlas.

Date Type Notes

Florentine

21-Oct-15 Nest Not active

18-Nov-13 Nest

15-Nov-13 Nest Not in use

30-Jul-13 Nest

15-Sep-09 Nest Small nest with no signs of use

18-Sep-08 Nest no birds observed nest reduced in size

21-Nov-05 Nest not in use

27-Jul-03 Nest

N


32

Conservation planners in Tasmania generally impose restrictions on activities for known Tasmanian

Wedge-tailed Eagle nests within 1 km (FPA 2013). Birds nesting within 1 km are generally considered

at risk from noise and visual disturbance. There are no eagle nests within this distance threshold in

the Tasmanian Natural Values Atlas, nor have any nests been identified via visual assessment by

personnel at the hatchery. Additionally, the construction phase of the drum filter would likely occur

outside of breeding season for Wedge-tailed Eagles. Therefore, the impacts upon known nesting

Tasmanian Wedge-tailed Eagles is considered likely to be low.

There is high-quality modelled Tasmanian Wedge-tailed Eagle habitat in the vicinity of the hatchery

with noise and visual disturbance from the installation and operation of the drum filters conceivably

discouraging raptors from establishing nests in the area. However, the disincentive is considered

unlikely to be significantly over and above the current operations of the hatchery (refer to section 3.7

for more detail) and specific consideration is being given to the drum filter design to ensure noise and

visual aspects of the infrastructure do not significantly impact upon native fauna in the area. There is

also very large areas of highly suitable nesting habitat in the region providing ample alternatives to

the habitat in the immediate vicinity of the hatchery.

3.2 Weeds and disease

• Are weeds and diseases that may affect native flora and fauna known to be present on or near the

site or are there reasons to expect their presence? If so, a survey and recommended control measures

are likely to be required.

• Does the proposal have the potential to spread weeds and diseases that may affect native flora and

fauna? If so, recommendations for ongoing weed and pathogen management should be presented in

the EER in accordance with the weed management and hygiene guidelines.

There is no record of weeds or disease in the vicinity of the Florentine Hatchery. It is not anticipated

that the installation and operation of the drum filter at the Hatchery will result in the spreading of

weed species.

During construction all construction machinery will be cleaned prior to and on leaving site to remove

all soil and botanic matter as described in Wash Down Guidelines for Weed and Disease Control Edition

1 (DPIPWE, 2004). Weed infested material will not be used as mulching to reduce the propagation of

weeds. During the construction phase an ongoing weed management program will be undertaken to

minimise weeds. Gravel and fill etc. will be sourced from areas considered low risk of importing

phytophthora to site.

3.3 Aquatic environment and wastewater

• Identify all protected environmental values for the receiving environment downstream of the outfall

and describe relevant uses of the downstream environment.

• Provide determined (from current operations) or estimated wastewater throughput volumes after

installation of the drum filters including seasonal variation and longer-term trends associated with

production levels.


33

• Determine water quality guideline values for key receiving water quality indicators to protect the

identified environmental values for the receiving waters.

• Propose effluent quality limits, including expected median, 90th percentile and maximum values for

BOD, non-filterable residue, thermotolerant coliforms, total and dissolved nitrogen, phosphorus,

conductivity and pH and any other potential contaminants of concern.

• Where guideline values will potentially be impacted then the extent of the required mixing zone must

be determined.

• Contingency measures for unforeseen circumstances that may require alternative options for

management of wastewater.

• Detail any therapeutic treatments that may be used in the hatchery and any potential impacts.

• Describe management of stormwater from the construction area during the installation of the drum

filter.

• Detail the management for draining and desludging of the current treatment ponds.

3.3.1 Aquatic Environment

3.3.1.1 Protected Environmental Values and downstream uses

As highlighted in section 2.2, two PEVs – ecosystem protection; recreational water quality and

aesthetics) were identified for the receiving environment (Florentine and Derwent River into Lake

Catagunya) of the Florentine Hatchery effluent water. These values are in line with the most relevant

uses of the Lake Catagunya including recreational fishing, boating and paddling.

Recreational fishing targets brown trout, with occasional catches of escapee rainbow trout and

Atlantic salmon. Brown trout populations are self-sustaining in the Lagoon and are widespread across

Tasmania. Atlantic salmon are occasionally actively stocked in in-land lakes across Tasmania, with

some stocking occurring in the Lagoon over the last 10 years. These stockings are for the purpose of

‘put and take’ recreational fishing, and do not result in permanently established populations. The

recreational fishery of Wayatinah Lagoon includes Lake Catagunya is considered small and frequented

by less than 100-200 anglers a year, with a low fishing effort and catch rate. Lake Catagunya is also

utilised for other recreational activities including boating and kayaking, usually during the summer

months.

Potential impacts to these identified PEVs could include:

• changes to water quality

• aesthetic changes (i.e. odour, water colour)

To mitigate any potential impacts to the identified PEVs from hatchery operations, the monitoring

program includes water quality guideline values (refer to section 3.3.1.2) and effluent limits (refer to

section 3.3.2.1). These guideline values and limits seek to provide water quality of a physical and

chemical nature that will support downstream ecosystem health.


34

3.3.1.2 Water quality guideline values

Water quality has been monitored upstream and downstream of Florentine Hatchery since 2015

(Table 9). Water quality data collected from upstream sites provides an opportunity to calculate site-

specific trigger values that can be set as a benchmark against which downstream water quality can be

assessed.

There have been 24 sampling events upstream of Florentine Hatchery since May 2015. The frequency

of sampling was approximately quarterly between May 2015 and March 2018, then changed to

fortnightly between March 2018 and September 2018. Nineteen parameters were measured from the

water samples however, not all parameters were sampled and/or analysed for each sampling event.

Sixteen analytes were sampled twenty or more times between 2015 and 2018. Temperature, DO

(mg/L) and DO (%) were only measured on 10, 13 and 5 occasions, respectively. Data available for

parameters were unevenly spread across years (quarterly sampling between 2015-2017; fortnightly

samples for 2018) and seasons (autumn and winter well represented; summer and spring poorly

represented; Table 10).

Values for some parameters often fell below lab detection limits. The laboratory (Analytical Services

Tasmania) reported these parameters with a prefix ‘<’ (e.g. <0.005 mg/L). In these cases, the upper

value of the detection limit was used in calculations. For example, a value of <0.005 mg/L was

converted to 0.005 mg/L.

Raw data for the upstream water samples at Florentine Hatchery is available in Appendix D.

Table 9 List of upstream sampling events from 2015, 2016, 2017 and 2018. Note that not all parameters were sampled and/or analysed during each sampling event.

2015 2016 2017 2018

8-May 29-Mar 11-Jan 13-Mar

7-Jul 28-Jul 27-Apr 26-Mar

18-Aug 18-Oct 27-Jul 11-Apr

16-Dec

18-Oct 19-Apr 3-May

16-May 5-Jun

21-Jun 17-Jul

16-Aug 18-Sep


ENVIRONMENTAL EFFECTS REPORT Table 10 Number of data points for each parameter by year and season. Parameter 1 refers to parameters measured in the Florentine Hatchery sampling program. Parameter 2 refers to the equivalent label in Water Quality Default Guideline Values for the Upper Derwent.

Parameter 1 Parameter 2 2015 2016 2017 2018 Autumn Winter Spring Summer Total

Florentine

Alkalinity 4 3 4 12 9 9 2 3 23

Ammonia 4 3 4 12 9 9 2 3 23

BOD 4 3 4 12 9 9 2 3 23

Coliforms 4 3 4 12 9 9 2 3 23

DO (% sat) DO (% sat)^ 0 1 1 11 6 3 2 2 13

DO (mg/L) DO (mg/L)^ 0 1 1 3 1 0 2 2 5

EC Cond^ 4 3 4 13 9 9 3 3 24

Hardness 4 3 4 12 9 9 2 3 23

Nitrate NO3 as N^ 4 3 4 12 9 9 2 3 23

Nitrite NO2 as N^ 2 3 4 12 8 8 2 3 21

pH pH^ 4 3 4 12 9 9 2 3 23

Phosphorus DRP as P^ 4 3 4 12 9 9 2 3 23

TDS 4 3 4 12 9 9 2 3 23

Temperature Temp (oC)^ 0 1 4 5 2 3 3 2 10

Total Mg 4 3 4 12 9 9 2 3 23

Total Nitrogen TAN as N^ 4 3 4 12 9 9 2 3 23

Total Phosphorus Total P as P^ 4 3 4 12 9 9 2 3 23

Total Zinc 4 3 4 12 9 9 2 3 23

TSS TSS* (1.5 µm) 4 3 4 12 9 9 2 3 23



Calculation of receiving Water Quality Guideline Values

The National Water Quality Management Strategy considers that the 80th percentile provides an

upper limit for stressors that cause problems at high values, while the 20th particle provides a lower

limit for stressors that cause problems at low values. These site-specific trigger values set a

benchmark against which future variation in water quality at sites can be assessed.

It is considered that sufficient information should be available from historical upstream sampling of

Florentine Hatchery to calculate preliminary guideline values for receiving water quality. The water

quality default guideline values for the Upper Derwent provide a set of relevant parameters and

these default guideline values can be referred to when data is insufficient.

Preliminary annual guideline values

The preliminary annual trigger values for 20th and 80th percentiles were calculated using all available

data (i.e. all water samples collected between 2015-2018) in the Excel formula PERCENTILE.INC.

Table 11 displays the preliminary annual trigger values.

It is important to note that the annual trigger values derived from the sampling data is subject to

yearly and seasonal bias because of (a) unbalanced sampling across years (see Table 10) and (b)

unbalanced sampling across seasons (see Table 10). This may have an effect on parameters with a

strong seasonal cycle, for example, the over-representation of cold water in autumn and winter

samples compared to spring and summer samples will result in temperature trigger limits that may

be considerably cooler than true conditions.

Preliminary seasonal guideline values

The water quality default guideline values for the Upper Derwent include seasonal values. The 20th

and 80th percentiles were calculated for each season for the Florentine Hatchery (see Table 12). It

should be noted that these values are considered to be preliminary values only and are subject for

review upon the accumulation of more data from sampling events.



Table 11 Annual default water quality guideline values for the Upper Derwent (DER) and (preliminary) derived water quality guideline values for Florentine Hatchery (FLO).

Site Period Value DO (mg/L)^ DO (% sat)^ Cond^ pH^ Turb^ Temp (oC)^ TAN

as N^ NO3 as

N^ NO2 as

N^ Total N as N^

DRP as P^

Total P as P^

TSS* (1.5 µm)

TSS^ (0.45 µm)

lower upper lower upper (µs/cm) lower upper NTU lower upper (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)

DER Annual Guideline 9.4 11.8 90.3 103.8 123.4 6.2 7.4 8.3 6.5 13.5 0.012 0.020 0.003 0.394 0.004 0.022 5.00 11.00

FLO Annual Guideline 11.1 12.8 100.4 108.9 224.8 7.6 8.2 NA 6.4 10.3 0.010 0.090 0.005 0.406 0.005 0.010 4.00 NA

FLO Annual #

Samples 5 5 7 7 24 23 23 NA 11 11 23 23 23 23 23 23 23 NA

NOTE: For Florentine Hatchery, lower (20th percentile) and upper (80th percentile) were calculated for DO, pH and temperature. Upper (80th percentile) values

were calculated for the remaining parameters, including conductivity (Cond). The total number of data points for Florentine Hatchery (FLO) are included.

Parameters with poor data resolution (n-11 measurements highlighted in red) and good resolution (n=>20 measurements highlighted in green).


38

Table 12 Seasonal default water quality guideline values for the Upper Derwent (DER) and preliminary derived water quality guideline values for Florentine Hatchery (FLO).

Site Period Value

DO (mg/L)^ DO (% sat)^ Cond^ pH^ Turb^ Temp (oC)^ TAN as N^

NO3 as N^

NO2 as N^

Total N as N^

DRP as P^

Total P as P^

TSS* (1.5 µm)

TSS^ (0.45 µm)

lower upper lower upper (µs/cm) lower upper NTU lower upper (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)

DER Summer Guideline 8.9 10.5 90.3 103.1 140.4 6.5 7.8 6.7 11.2 16.9 0.011 0.008 0.003 0.370 0.004 0.023 5.00 15.20

FLO Summer Guideline 10.7 11.9 102.0 113.3 299.2 8.1 8.2 NA 13.6 14.8 0.007 0.069 0.004 0.328 0.005 0.010 3.2 NA

FLO Summer # Samples 2 2 2 2 3 3 3 NA 2 2 3 3 3 3 3 3 3 NA

DER Autumn Guideline 9.7 11.7 89.5 103.8 124.4 6.3 7.6 6.0 7.6 12.2 0.011 0.020 0.004 0.323 0.004 0.016 5.00 12.00

FLO Autumn Guideline 13.0 13.0 105.0 109.0 307.4 7.7 8.3 NA 7.1 7.3 0.010 0.068 0.004 0.504 0.006 0.014 9.6 NA

FLO Autumn # Samples 1 1 6/1 6/1 9 9 9 NA 2 2 9 9 9 9 9 9 9 NA

DER Winter Guideline 11.1 13.0 90.5 105.1 116.5 6.0 7.0 13.0 4.5 7.0 0.016 0.071 0.005 0.529 0.004 0.028 10.00 7.00

FLO Winter Guideline NA NA 100.8 102.0 172.4 7.6 7.9 NA 4.5 6.1 0.009 0.097 0.005 0.414 0.004 0.010 4.0 NA

FLO Winter # Samples NA NA 3 3 9 9 9 NA 3/4 3/4 9 9 9 9 9 9 9 NA

DER Spring Guideline 9.5 11.8 90.5 103.7 114.6 6.2 7.3 9.1 7.0 11.7 0.012 0.009 0.004 0.392 0.004 0.022 5.00 8.20

FLO Spring Guideline 11.6 12.5 101.5 107.0 186.2 7.8 8.0 NA 7.9 9.1 0.009 0.105 0.003 0.298 0.004 0.010 2.0 NA

FLO Spring # Samples 2 2 2 2 3 2 2 NA 3 3 2 2 2 2 2 2 2 NA

NOTE: For Florentine Hatchery, lower (20th percentile) and upper (80th percentile) were calculated for DO, pH and temperature. Upper (80th percentile) values

were calculated for the remaining parameters, including conductivity (Cond). The total number of data points for Florentine Hatchery (FLO) are included.

Parameters with poor data resolution (n-8 measurements highlighted in red) and good resolution (n=>9 measurements highlighted in green).



3.3.2 Wastewater

3.3.2.1 Existing effluent quality

As discussed in the previous section 3.3.1.2, there have been 24 sampling events upstream of the

Florentine Hatchery settlement pond since May 2015. The frequency of sampling was approximately

quarterly between May 2015 and March 2018, then changed to fortnightly between March 2018 and

September 2018. There have been 12 sampling events downstream of the hatchery since February

2018.

Nineteen parameters were measured from the water samples. Not all parameters were sampled

and/or analysed for each sampling event. Data available for parameters were unevenly spread

across years (quarterly sampling between 2015-2017; fortnightly samples for 2018) and seasons

(autumn and winter well represented; summer and spring poorly represented).

The median, 90th percentile and maximum values for settlement pond and downstream sampling

locations for the Florentine Hatchery were calculated (Table 13) using the raw data from the Florentine

sampling program (refer to Appendix E for the raw data).

It should be noted that the sample collection is unbalanced across years and seasons and statistics

may be skewed towards winter and autumn conditions; and for some seasons (i.e. spring/summer)

and some parameters (i.e. dissolved oxygen and temperature) are based on very small sample sites.


ENVIRONMENTAL EFFECTS REPORT Table 13 Median, 90th percentile and maximum parameter values for water samples taken from the settlement pond and downstream of Florentine Hatchery.

Pond Downstream

Median 90th Max Median 90th Max

Florentine

Alkalinity mg CaCo3 71.0 154.2 161.0 74.0 100.0 157.0

Ammonia mg-N/L 0.340 0.726 0.780 0.150 0.537 0.720

BOD mgO2/L 5.0 8.8 11.0 5.0 6.9 8.0

Coliforms* cfu/100mL 20.0 58.0 160.0 25.0 86.0 120.0

DO mg/L 11.2 13.1 13.4 12.1 12.7 12.8

DO % 106.0 109.1 112.3 102.2 106.0 106.5

EC uS/cm 178 329 359 176 229 340

Hardness mg CaCoO3 72.000 155.000 166.000 78.500 105.900 169.000

Nitrate mg-N/L 0.110 1.420 4.900 0.150 0.881 2.500

Nitrate_Nitrite mg-N/L 0.120 1.600 4.900 0.155 0.899 2.500

Nitrite mg-N/L 0.007 0.021 0.052 0.009 0.016 0.024

pH 7.4 7.8 8.1 7.6 7.7 7.8

Phosphorus mg-P/L 0.063 0.192 0.330 0.050 0.089 0.170

TDS mg/L 128.0 194.4 208.0 123.5 149.0 199.0

Temperature deg C 7.4 13.4 15.3 6.8 10.7 13.3

TKN mg-N/L 0.980 1.900 2.500 0.940 1.200 1.800

Total_Ca mg/L 24.700 55.300 58.900 27.200 37.080 60.100

Total_Mg mg/L 2.380 4.106 4.580 2.600 3.231 4.670

Total_N mg-N/L 1.400 3.220 6.600 1.200 2.080 3.500

Total_P mg-P/L 0.140 0.394 0.850 0.105 0.307 0.360

Total_Zn µg/L 5.0 9.0 18.0 7.0 10.8 13.0

TSS mg/L 5.0 9.8 22.0 4.0 9.8 25.0 *Coliforms = Thermotolerant coliforms



3.3.2.2 Interim effluent quality limits

Interim effluent quality limits would generally be determined on a seasonal basis in order to reflect

influencing factors such as biomass levels/feed rates and climatic factors such as rainfall. However,

due to the limitation in the dataset as described in section 3.3.2.1, the interim limits have been

based on the 90th percentile values calculated from the settlement pond dataset. The pond values

are considered equivalent to ‘end-of-pipe’ values as the samples are taken from the point just

before discharge to the river.

Table 14 describes the proposed interim effluent quality limits that will be implemented for

Wayatinah pond values during the construction and commissioning period of the drum filter. A

review of the interim limits will be undertaken six months after commissioning to establish seasonal

values that more accurately reflect the hatchery operation with the drum filter.

Table 14 Interim effluent quality limits for Florentine Hatchery

Parameter Interim Limit Value

Alkalinity mg CaCo3 154.2

Ammonia mg-N/L 0.726

BOD mgO2/L 8.8

Coliforms* cfu/100mL 58.0

DO mg/L 13.1

DO % 109.1

EC uS/cm 329

Nitrate mg-N/L 1.420

Nitrate_Nitrite mg-N/L 1.600

Nitrite mg-N/L 0.021

pH 7.8

Phosphorus Dissolved Reactive mg-P/L 0.192

TDS mg/L 194.4

Temperature deg C 13.4

TKN mg-N/L 1.900

Total_Ca mg/L 55.300

Total_Mg mg/L 4.106

Total_N mg-N/L 3.220

Total_P mg-P/L 0.394

TSS mg/L 9.8

3.3.3 Alternative options for Wastewater Management

As described in section 2.4, a range of options have been assessed to improve the treatment of

effluent water being discharged from Florentine Hatchery. These options included increased de-

sludging, increasing the settlement pond retention time, develop wetlands, bio-filtration and

installation of drum filter. Through these scoping discussions it was established that the installation

and operation of drum filters was the most viable option in relation to site constraints, existing


42

hatchery operations and expected environmental performance. It should also be noted that de-

sludging of the settlement pond will still occur on an annual basis at Florentine Hatchery.

3.3.4 Therapeutic treatments

A wide range of chemicals are used for a variety of purposes at the SALTAS facilities (Table 15). Some

chemicals are used routinely, while others are used in response to specific events (e.g. disease

management, animal transport). SALTAS policy as outlined in its internal procedure ENV-001 is that all

chemical agents (including antibiotics) are to be used in accordance with the manufacturer’s

guidelines and all containment/disposal procedures are carried out in line with MSDS (safety data

sheet) standards. The chemical agents listed in Table 15 are generally used in volumes well below

guideline recommendations and most are used to treat tanks within the recirculating aquaculture

system (RAS).

Table 15 Chemical agents used at Tassal and Saltas hatchery facilities (data source: Tassal and SALTAS)

Agent Use description

Disinfectant, cleaning etc.

Formalin Aqueous Formaldehyde stabilized with methanol - disinfectant and anti-parasitic

Virkon (Aquatic) Inorganic disinfectant, fish tank treatment, used at ca. 2 ppm (100 g at a time)

Chloramine T Routine cleaning - biocide and disinfectant

Sodium hypochlorite Routine cleaning

Ethanol Varying topical uses

Water quality control

Salt Sodium chloride. Used for tank treatment and brining of sand filters

Hydrated lime Calcium hydroxide. Routine pH control

Hydro-mags Magnesium hydroxide. Routine pH control

Sodium bicarbonate Routine pH control

Fish anaesthetics

Benzocaine Anaesthetic

Clove Oil Anaesthetic, used during harvesting and transport

Aqui-S Water dispersible liquid anaesthetic, used during harvesting, husbandry and transport

Disease/growth control

Yersinivac-B Whole-cell vaccine for Yersinia infection prevention

Antibiotic Typically Trimethoprim, varying formulations, mixed with feed

3.3.5 Stormwater, sediment and runoff control

The footprint of the proposed works would have no impact on the existing stormwater drainage

systems in the surrounding area. All disturbed ground would be brought to pre-existing standard or

better. Surface drains directing groundwater to the settlement pond would be installed as required to

control erosion of the new finished surface.


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Sediment and runoff control measures have been identified and will be implemented during the

construction phase of the project. These identified measures include:

• All spoil stockpiles to be maintained to industry best practice through the use of sediment

fences, earth bunds and appropriate soil stabilisation techniques. This includes re-contouring

and re-vegetating stockpiles.

• Installation of appropriate sized sediment control basins, gross pollutant traps, and other

erosion and sediment control measures (sediment fencing, filter socks, etc.) as required.

• Contaminated water to be removed from the site using an appropriately licensed transport

contractor and transferred to an approved treatment facility.

• All stormwater management infrastructure to be regularly monitored and maintained.

As part of the proposed works, the existing settlement pond would be brought back into service once

the new drum filter system is commissioned. It is anticipated the settlement pond shall have minimal

solids loading due to the efficiency of the proposed drum filter upstream. Surface drains in the

immediate area around the new drum filter structure shall direct surface water to the settlement pond

to manage and prevent erosion.

3.3.6 De-sludging

During the construction period while the outflow water is being diverted, the settlement pond shall

be emptied and desludged. Desludging would be undertaken in line with the draft Tassal Freshwater

Hatcheries Wastewater Solids Management Plan.

3.4 Significant areas

• Is the proposal located within or adjacent to an existing reserved area (e.g. National Park, State

Reserve, Regional Reserve, Nature Reserve, Forest Reserve or Conservation Area)? If yes, provide

details.

Florentine Hatchery is more than 4 km downstream of the World Heritage Listed Franklin-Gordon Wild

Rivers National Park. As the hatchery is an existing operation located downstream the construction

and operation of the drum filter will not have any impacts on the National Park.

There are no other areas of significance within the vicinity of the proposed activity.

3.5 Air emissions

• Demonstrate, any air emissions at the various stages of the wastewater treatment will not cause

environmental harm (includes environmental nuisance). Provide evidence, potential odour sources

will be enclosed and any odour will be maintained at levels to satisfy the requirements of the

Environmental Protection Policy (Air Quality) 2004.

• Identify and describe each potential source of air emissions (i.e. point or fugitive).

• Describe the management of all potential sources of air emissions, including solid organic waste.

Discuss design features of the equipment, infrastructure and systems, and other processes, strategies

or procedures, which will mitigate atmospheric emissions.


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• Discuss contingency management for unforeseen events, such as excessive volume of solid organic

waste on site, which could comprise the function of the system/facility.

Dust and odour are identified as potential air emissions resulting from the proposed activity. These

emissions could potentially cause a nuisance to the hatchery staff and visitors to the site.

3.5.1 Odour Management

Solid organic waste (sludge) is the most significant source of odour resulting from the operation of the

drum filter. The generated sludge would be stored in an enclosed polyethylene tank that would be

emptied every four days. The waste would be transported in an enclosed tanker. The odour emissions

are expected to be low to negligible due to:

• Experience from other existing hatcheries (Tassal’s Russell Falls and Rookwood facilities) that

produce biosolids similar in nature. Employee observations from these hatcheries have

found that odour is only occasionally noticeable in distances less than 10 m from the tank

and there is no obvious odour being emitted from the sludge clarifier (as per observations at

Russell Falls Hatchery). There have also been no reports from residents close to these

hatcheries in relation to odour complaints.

• Distance of nearest residents (Wayatinah Village) is more than 7 km away with no line of

sight due to topography and vegetation.

As part of the draft Biosolids Management Plan the location, storage arrangements and removal

frequency of the sludge produced will be detailed and odour mitigation methods will be implemented

if required.

It should also be noted that Florentine Hatchery currently produces and manages biosolids from the

RAS and desludging of the settlement pond and no complaints relating to odour emissions have been

received.

In the unlikely event that odour concentrations become noticeable to sensitive receptors, SALTAS

would engage an odour specialist to conduct an assessment and will investigate odour mitigation

options.

3.5.2 Dust

There may be an increase of dust generation at the Florentine Hatchery site during the construction

phase. Dust prevention and mitigation strategies are for the construction of the drum filter include:

• Surfaces of work and heavy vehicle movement areas are to be of compacted gravel to

minimise vehicle generated dust emissions;

• Water tanker and water sprays to be used to suppress dust when necessary;

• Spray stockpiles with water to suppress dust when necessary;

• Service and maintain all plant and equipment powered by internal combustion engines to

ensure emissions comply with the relevant legislation;


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• Loads on trucks to be covered to prevent dust generation; and

• Vehicles not to be left idling unnecessarily.

3.6 Solid wastes

• Will the activity produce or result in solid wastes? If yes, provide details of the nature of the waste

types and proposed methods for reuse, recycling or disposal of such wastes.

• Can generation of the wastes be reduced or avoided in the first place?

The proposed activity will result in the production of solid wastes both during and after construction.

During construction the following mitigation measures will be implemented to avoid/minimise

generation of solid wastes:

• All contractors must define the likely solid and controlled wastes they will produce and how

they will be disposed of.

• Weekly inspections to include litter checks and consequent clean-up if necessary.

• Controlled waste to be removed from the site on a progressive basis and not allowed to

stockpile unduly.

• Store and disposal of any general garbage to licensed landfill. Litter bins to have secure lids

to prevent access by animals.

• Construction waste to be sent to recycling where practicable.

• Segregate and recycle general solid wastes generated by construction activities.

Post construction solid waste will be generated in the form of organic sludge from the drum filter.

This waste will be managed under the draft Biosolids Management Plan which will include removal

of the waste by a third party contractor who is authorised to transport controlled wastes under

EMPCA or subordinate legislation. The waste would be transported to an authorised composting

facility for final disposal.

3.7 Noise emissions

• Will the activity include fixed or mobile equipment that emits noise? If yes, provide details of the

noise sources including size, power ratings, noise attenuation and hours of operation. Show the

expected locations of the noise sources on the site plan and locations of nearby residences and other

noise sensitive premises on the area map.

• Describe the potential impacts from noise generated by the activity and the need or otherwise for

detailed technical review and additional mitigation measures.

The main noise sources associated with the drum filter installation and operation include truck

movements, ancillary equipment and excavation equipment/machinery.

Construction

• Contractor construction traffic (6-8 cars and 2 trucks per day). Note no material is being

removed from site.


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• Earthmoving equipment (standard excavation for period of 3 weeks)

• Earthmoving equipment (rock removal i.e. ripping or hydraulic hammer for estimated 3

days)

• Truck reversing signal

• Mobile crane operation (2-3 days)

Operation – drum filter

• Drum filter spray bar - primary noise source similar to other drum filters running full-time at

Tassal’s Rookwood and Russell Falls hatcheries.

• Sludge pump, water pump – start/stop operation

Operation – sludge plant

• Lamella plate clarifier– start/stop operation

• Auxiliary blower and diffuser system in each sludge tank – primary noise source with plant

running full-time

Potential impacts from these noise sources could include:

• Nuisance to on-site staff and visitors

• Disturbance to nesting Wedge-tailed Eagle

To mitigate these potential impacts during the construction phase of the project the following control

measures would be implemented:

• Construction activities, including entry and departure of vehicles shall be restricted to the

hours 7.00am to 7.00pm (Monday to Friday) and 8.00am to 5.00pm (Saturdays) and at no time

on Sundays. Work outside of these hours can only occur if:

o delivery of materials is required for safety or emergency reasons;

o emergency work is required to avoid loss of life, property damage or environmental

damage; and/or

o any other work agreed between SALTAS and neighbours.

• Ensure construction equipment has adequate noise and vibration control equipment and is

maintained in good working order. Measures include:

o Earth moving equipment fitted with residual class mufflers

o Acoustic enclosures for any diesel generators and/or air compressors

o Where possible, use high pressure hydraulic systems instead of pneumatic hammers

to split rock.

• Properly maintaining vehicles and equipment to ensure noise source levels are not exceeded.

• Monitor excessively noisy equipment and modify or remove from site if noise levels are

exceeded.


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To mitigate the on-going noise sources as part of the drum filter operation SALTAS will consider

potential noise sources and levels as part of the detailed design of the drum filter and identify any

necessary additional noise reduction measures (such as acoustic barriers) to ensure that noise levels

are maintained at the target levels.

The operation of the drum filter in relation to noise nuisance is considered to be very minimal (if not

negligible). The Florentine Hatchery is surrounded by Forestry owned plantations and the nearest

residents are located at Wayatinah Village approximately 6 km away, with no line of sight to the

hatchery. It should also be noted that the hatchery has been operating for 32 years with no noise

complaints resulting from its operation.

In relation to disturbance to nesting Wedge-tailed Eagles, as described in section 3.1, the nearest nest

was last surveyed in 2015 and was noted as not active. This nest is also approximately 1.5-1.7 km from

the hatchery with no line-of-sight to the hatchery. Additionally, the construction of the drum filter

would likely not occur during the Wedge-tailed Eagle breeding season.

It should also be noted that current operations at the hatchery could be used as a baseline for visual

and noise impact on wildlife in the area (including Wedge-tailed Eagles). Annual de-sludging of the

settlement pond (usually in Oct-Nov) includes use of an excavator and/or pumps which are equivalent

or similar to the machinery required during the construction phase of this proposal.

Other machinery (such as cranes) that may be required for discrete small pieces of construction work

have previously been used on site for past developments such as the new RAS building. In addition,

large trucks both on-site (such as smolt trucks and waste removal vehicles) and off-site (log trucks)

generally frequent the area.

Overall, it is considered that the activities associated with the drum filter installation would not

significantly differ in scale and intensity from the types of activities previously undertaken at this site.

This proposal is not considered to expose protected wildlife (such as Wedge-tailed Eagles) to the types

of machinery or operations generally regarded as threatening processes. The proposed installation of

drum filters at the Florentine Hatchery is unlikely to significantly impact on Wedge-tailed Eagle

populations, their behaviour or breeding success.

Appendix F is an assessment provided by noise specialist Steven Carter (Environmental Dynamics)

summarised that noise impact from construction and operations would be low. SALTAS however, is

committed to commissioning a further assessment post installation if deemed necessary.

3.8 Transport impacts

• Will the activity result in or require substantial transport of goods or materials to or from the site,

which may affect the amenity of the surrounding area? If yes, provide details such as vehicle types,

number of vehicle movements, times of movements and route(s).

The construction and installation of the drum filter will result in infrastructure and other materials

being transported to the Florentine Hatchery site. The traffic movement will be restricted to the


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existing traffic paths, and all vehicles will be restricted to daylight hours (7:00am to 7:00pm Monday-

Friday; 8:00am to 5:00pm Saturday; no movement on Sundays).

Once the drum filter is operational and sludge is being generated, there will be additional truck

movements to remove the sludge from site. Removal of the sludge is expected to occur every 2-3

days during peak biomass periods. The additional truck movement is not expected to affect the

amenities of the surrounding area as the increase is minimal (and based on ‘peak volumes’) and the

area/route is subject to regular traffic movement of logging trucks and fish transport tankers.

3.9 Other off-site impacts

• Does the activity have the potential to generate any other off-site impacts that may affect the

amenity of residences or other sensitive uses?

• Describe the main processes which occur in the commissioning phase, the likely duration of the

commissioning phase and the criteria used to determine whether commissioning has been

completed.

• Comprehensive description of the management arrangements pertaining to the hatchery-wastewater

and existing settlement pond during the commissioning phase, particularly the management of

untreated wastewater.

Refer to section 3.3 of this document for details of impacts to downstream environment and its

uses.

There are no other off-site impacts that have been identified that is relevant to the proposed

activity.

3.10 Hazardous substances

• Has the activity involve the use and/or storage of hazardous substances that have the potential to

cause environmental harm if released? If so, provide details of the nature and quantity of the

materials, their storage location and methods and proposed measures to prevent their release.

• Describe proposed measures for responding to accidental spillage or escape of hazardous substances.

• Identify all controlled wastes likely to be present on the site, with reference to standard classification.

• Identify all dangerous goods likely to be present of the site.

During construction works unleaded petrol and/or diesel will be stored on site for refuelling of the

civil plant. In the unlikely event of a spill event adequate spill controls and clean up kits will be easily

accessible on site and all construction personnel will be adequately trained to transfer fuels and

manage spill clean-up.

Cleaning and wash down chemicals may also be stored on site.

All hazardous substances will be managed in accordance with Australian Standard (AS 1940:2017) for

the storage and handling of flammable and combustible liquids.


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3.11 Site contamination (historical)

• Has the site on which the activity is to be located been used in the past for activities which may have

caused soil or groundwater contamination? If so, provide details.

Florentine Hatchery has been operated for over 30 years. No other potentially contaminating activity

is known to have been carried out at the site. No spill incident is known to have taken place at the site.

3.12 Heritage

• Is the proposed activity on or near a place listed on the Tasmanian Heritage Register or Tasmanian

Historic Places Inventory? If yes, provide details.

• Describe any potential effects on historic heritage (including Aboriginal heritage) and proposed

management measures.

No historic heritage values have been identified in the vicinity of the Florentine Hatchery and the

proposed activity (construction area) will occur within the boundaries of the existing operation.

3.13 Sites of high public interest

• Details in relation to the activity’s proximity to places of public interest (such as recreational fishing

areas, etc.).

Refer to section 2.2 of this document for details on recreational uses for the area downstream of

Florentine Hatchery.

3.14 Monitoring and review

• Detail monitoring and maintenance programs to support best practice environmental management.

The monitoring program should report on key water quality parameters for treated wastewater (at

end-of-pipe. Specify reporting arrangements of monitoring data and observations.

• Describe any surveys, studies or monitoring proposed or underway in relation to the key issues for the

proposal and include any proposed monitoring points on the site plan.

The current monitoring program at Florentine Hatchery includes fortnightly water quality sampling of

nutrients, chemicals and physiochemical characteristics (refer to Table 16 for list of parameters) at

three location sites (upstream of hatchery, outfall from settlement pond and downstream of hatchery

– refer to Figure 11) and bi-annual macroinvertebrate sampling at upstream (Easting 459395, Northing

5301039) and downstream (Easting 460314, Northing 5301367) locations.

The frequency of fortnightly water quality sampling was initiated in March 2018 to develop a more

robust dataset for the Florentine Hatchery. The water quality program will continue with fortnightly

sampling until the drum filter has been operating for six months. The sampling program will then be

reduced to monthly sampling. This change to sampling frequency is still in-line with best practice

methodologies and is the frequency required at other finfish flow-through hatcheries.


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Bi-annual macroinvertebrate sampling will also continue with an accompanying assessment report

developed for each sampling event.

Table 16 Water quality parameters measured for monitoring program

Parameter Unit

Temperature °C

Dissolved Oxygen % and mg/L

pH pH units

Conductivity (EC) µS/cm

Total Dissolved Solids (TDS) mg/L

Total Suspended Solids (TSS) mg/L

Ammonia mg/L

Total Alkalinity mg CaCO3/L

Hardness mg CaCO3/L

Total Kjeldahl Nitrogen (TKN) mg/L

BOD mg/L

Nitrate mg/L

Nitrate + Nitrite mg/L

Nitrite mg/l

Total Nitrogen mg/L

Total Phosphorus mg/L

Ca (total) mg/L

Mg (total) mg/L

Zn (total) µg/L

Dissolved Reactive Phosphorus mg/L

Thermocoliforms cfu/100mL

In addition to the water quality monitoring program, a short-term intensive monitoring of effluent

discharge for periods of 24-48 hours is proposed to be undertaken on a quarterly rotation over a

period of 18 months to assess the degree of diurnal and seasonal variability in water quality

parameters. These occasions would be timed to actively select ‘worst case’ conditions (such as during

peak biomass periods) and provide information on maximum likely analyte concentrations. The data

from this monitoring would be analysed to assess any in-farm improvements to water quality

management that may be required, as well as assess the statistically representativeness of the routine

monthly monitoring of the hatchery effluent and receiving watercourses.


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Figure 11 Coordinates and diagram of water quality sampling locations for Florentine Hatchery

A review of the preliminary water quality guideline values and interim effluent limits is proposed for

six-months post commissioning of the drum filter. This review is proposed to be conducted by a

freshwater specialist (in conjunction with the EPA) who would assess the gathered data to date to

assess the monitoring program and to establish if (a) finalised water quality guideline values and

effluent limits can be set or; (b) if more monitoring and changes to the interim limits and proposed

values is required.

Ongoing installation and development of water quality treatment mitigation would be conducted as

part of an adaptive continuous improvement strategy. The drum filters will be assessed for

performance, and modifications made where necessary to both the installations themselves (filter

size, numbers of screens, settlement pond management) and other on-farm practices – all in response

to the findings of the receiving environment monitoring.

As part of the monitoring programs, SALTAS would provide an annual report to the EPA including all

water quality data, biomonitoring assessments and any other relevant information within the

reporting period.

SITE COORDINATES (GD94 MGA55)

F001 – upstream of the hatchery (on the Florentine River)

459436E 5301067N

F002 – settlement pond at the hatchery – effluent release to river

460184E 5301286N

F003 – downstream of hatchery (on the Florentine River)

460231E 5301344N


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3.15 Rehabilitation

• Describe proposed decommissioning and rehabilitation measures in the event of cessation of the

activity.

• Describe any proposed rehabilitation of disturbed native vegetation.

As the proposed activity will not involve any disturbance of native vegetation and does not have a

finite life, no rehabilitation plan is warranted at this stage. However, SALTAS is committed to its

responsibilities and obligations in respect to decommissioning and rehabilitation if cessation of

hatchery operations was to occur.



4 PART D - Management Commitments

• Specific, unambiguous written commitments for avoiding, minimising and managing the potential environmental impacts of the proposal (as identified

in Part C) should be documented in Part D.

The preceding description of environmental management issues and approaches leads to the following commitments, which will be

implemented by SALTAS under this EER (Table 17).

Table 17 Commitments table

No. Commitment Timeframe By Whom

Construction phase

1 A Construction Safety and Environmental Management Plan (CEMP)will be implemented, appropriate to the construction complexity and risks

Completed

(Appendix G)

Construction contractors

2 Training of the management requirements contained in the CEMP will be provided to contractors prior to commencement of construction

Before construction Project manager

3 Development and implementation of a weekly inspection checklist of the CEMP

On-going through construction

Project manager

Operation phase

4 Finalise the draft Tassal Freshwater Hatcheries Wastewater Solids Management Plan including obtaining the appropriate transport and disposal approvals

Before commissioning Tassal Environment Dept.

5 Undertake fortnightly water quality sampling as per parameters outlined in Table 16 and at the locations outlined in Figure 11.

On-going Tassal Environment Dept.

6 Undertake a short-term intensive monitoring of effluent discharge for periods of 24-48 hours is proposed to be undertaken on a quarterly rotation over a period of 18 months to assess the degree of diurnal and seasonal variability in water quality parameters

On-going Tassal Environment Dept.


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7 Review all monitoring data and the preliminary water quality guideline values and interim effluent limits

Six months post commissioning of drum filter

Tassal Environment Dept.

8 Review on-going monitoring program Six months post commissioning of drum filter

Tassal Environment Dept.

9 Provide annual report on monitoring data Annually Tassal Environment Dept.



5 PART E - Public and Stakeholder Consultation

• Has public consultation taken place (such as with government agencies, community groups or

neighbours), or is it intended that consultation will take place? If so, provide details.

The proposed activity has been presented and discussed with the Central Highlands Council and

Sustainable Timber Tasmania (STT) who both have indicated full support. The proposal will go through

a development application (DA) process, which will have opportunities for community input.

The small size of the drum filter, its location within the existing hatchery boundaries, the

environmental controls that will be implemented during and after installation, and the distance/native

forest buffer to nearest neighbours mean that no specific community consultation outside the DA

process is deemed necessary.


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6 References

Bell, P. and Mooney, N. J. (1999). Wedge-tailed Eagle Recovery Plan, 1998-2003. Tasmania, Department of

Primary Industries, Water and Environment.

Brown, W.E. and Mooney, N.J. (1997). Modelling of the Nesting Habitat of the Wedge-tailed Eagle (Aquila

audax fleayi) in Tasmania. Unpublished Report to the Tasmanian RFA Environment and Heritage Technical

Committee, Commonwealth of Australia and State of Tasmania.

Bureau of Meterology. (2018) Water Data Online. http://www.bom.gov.au/waterdata/ (accessed October

2018)

Bureau of Meterology. (2018). Weather Station Directory. http://www.bom.gov.au/climate/data/stations/

(accessed July 2018).

Davies, P. (2017). Biodiversity-focused environmental impact assessment freshwater aquaculture facilities

providing smolt to Tassal. (unpublished document).

DPIPWE (2003). Environmental Management Goals for Tasmanian Waters – Derwent River Catchment.

http://epa.tas.gov.au/Documents/Derwent_River_Catchment_Final_Paper.pdf

DPIPWE (2004). Tasmanian Washdown Guidelines for Weed and Disease Control.

http://dpipwe.tas.gov.au/Documents/Washdown-Guidelines-Edition-1.pdf

Freshwater Systems (2015). Hatchery ASC Macroinvertebrate Context Report (October 2015). (unpublished

document).

Forest Practices Authority (FPA) (2013). Wedge-tailed Eagle Nest Monitoring Project 2007-12: Nest site use,

timing of breeding, and review of the nesting habitat model’. Report to Roaring 40s, Threatened Species and

Marine Section (DPIPWE), April 2013, Forest Practices Authority Scientific Report.

Forest Practices Authority (FPA) (2014). Wedge-tailed eagle nesting habitat model. Fauna Technical Note No.6,

Forest Practices Authority, Hobart, Tasmania.

LISTMap. (2018) https://maps.thelist.tas.gov.au/listmap/app/list/map

http://www.bom.gov.au/waterdata/

http://www.bom.gov.au/climate/data/stations/

http://epa.tas.gov.au/Documents/Derwent_River_Catchment_Final_Paper.pdf

http://dpipwe.tas.gov.au/Documents/Washdown-Guidelines-Edition-1.pdf

https://maps.thelist.tas.gov.au/listmap/app/list/map