scalpay, isle of skye · scalpay, isle of skye autodepomod modellin g report 12 .2016v1 report...

Scalpay, Isle of SkyeAUTODEPOMOD MODELLIN G REPORT

12 .2016V1REPORT WRITTEN BY ENVIRONMENTA L ANALYST)

ENVIRONMENTAL MAN AGER)

Registered in Scotland No. 138843Registered Office, 1st Floor, Admiralty Park, Admiralty Road, Rosyth, FIFE, KY11 2YW

Marine Harvest ( Scotland) Limited, Stob BanHouse, Glen Nevis Business Park, Fort William, PH33 6RX

01397 715078 01397 703626

Marine Harvest ( Scotland) Limited, Stob BanHouse, Glen Nevis Business Park, Fort William, PH33 6RX

http:// marineharvest. com

Fish Farm Consent ModellingScalpay 16vF1 2016 Results

1

CONTENTS

Page

EXECUTIVE SUMMARY 1

1 INTRODUCTION 2

2 MODEL INPUT DETAILS 3

2.1 HYDROGRAPHIC DATA 3

2.2 SITE DETAILS 5

2.3 RUN DETAILS 6

3 MODELLING RESULTS 7

3.1 BIOMASS RESULTS 7

3.1.1 TRANSECT AND SAMPLING STATIONS 8

3.2 IN-FEED TREATMENTS 10

3.2.1 SLICE 10

3.3 BATH MODEL RESULTS 11

4 RESULTS AND CONCLUSIONS 12

REFERENCES 14


1

List of Figures

Figure 1 Location of the Salmon Farm ................................................................................. 2

Figure 2 Site current direction frequency from the surface current meter ............................. 4

Figure 3 bathymetry and cage layout ................................................................................... 6

Figure 5 Location of the selected and spare transects ......................................................... 8

Figure 6 Cross-sections of both the selected and spare transects respectively ................... 9

Figure 7 EmBZ concentrations for run 1 (118 days) .......................................................... 10

List of Tables

Table 1 Summary of Results ............................................................................................... 1

Table 2 A summary of the mean and residual currents recorded at the site......................... 4

Table 3 Project Information ................................................................................................. 5

Table 5 Selected and Spare Transect Starting Points ......................................................... 8

Table 6a&b The details of the three selected and spare survey stations respectively .......... 9

Table 7 Modelling Results Summarised ............................................................................ 13


1

EXECUTIVE SUMMARY

This report has been prepared by Marine Harvest ( Scotland) Ltd. to meet the requirementsof the Scottish Environment Protection Agency ( SEPA) for the purpose of assessing anapplication to install equipment and consequent biomass, and for consent to use sufficientsealice treatments in a marine salmon farm, via AutoDepomod and dispersion modelling. The report describes biomass, in-feed and bath treatment modelling results for the Scalpaysite, a summary of which is provided in Table 1 below. The report held centrally, andpreviously accredited, by SEPA (AMMR11v02) details modelling methods used.

Table 1 Summary of Results

SITE DETAILS

Site Name: ScalpaySite location: Isle of Scalpay, Isle of Skye

Peak biomass (T): 2,500

CAGE DETAILS

Number of cages: 12Cage dimensions: 120m Circumference

Working Depth (m): 12

Cage group configuration: 2(2x3), 75x70m matrix

HYDROGRAPHIC SUMMARY

Surface CurrentsAverage Speed (m/s) 0.068

Residual Direction 0.040m/s at 323°G

Wind-Influence Slight

Middle CurrentsAverage Speed (m/s) 0.060m/s


Seabed CurrentsAverage Speed (m/s) 0.053m/s


BENTHIC MODELLING

Max fish biomass proposed (T) 2,500t

Max Average Stocking Density (kg/m³) 15.1482

Distance to the 30ITI contour (m) 139.4

Direction of transect ( T) 356.3

IN-FEED TREATMENTS

Recommended consent mass EmBZ (g) 4,375

Equivalent Fish Biomass (T) 12500

Maximum Treatment Amount EmBZ (g) 875

BATH TREATMENTS

Recommended consent mass in 3hrs Azamethiphos 269.3g cage/treatment, 1.2treatments/ day

Recommended consent mass in 24 hrs Azamethiphos 687.7g cage/treatment, 3treatments/ day

Recommended consent mass in 3 hrs Cypermethrin48.7g cages/treatment, 4.3

treatments/ day

Recommended consent mass in 3 hrs Deltamethrin18.3g cages/treatment, 4

treatments/ day


2

1 INTRODUCTION

This report has been prepared by Marine Harvest to meet the requirements of the ScottishEnvironment Protection Agency ( SEPA) for the purpose of assessing an application toinstall equipment and consequent biomass, and for consent to use sufficient sealicetreatments, via AutoDepomod and dispersion modelling. The report describes modellingresults for a new site off the neighbouring island of Scalpay (Figure 1) to determine EQS-compliant biomass and sea-lice treatment levels for the proposed equipment. Reportnumber AMMR11v02 which is held centrally, and has been previously accredited, by SEPA, provides details of the generic modelling methods used.

Figure 1 Location of the Salmon Farm

North

Isle of Scalpay


3

2 MODEL INPUT DETAILS

2.1 HYDROGRAPHIC DATA

The site data was collected by Marine Harvest for the purpose of assessing a consentapplication with the AutoDepomod software. Methods of the data collection and analysisfollowed current SEPA guidelines (SEPA, 2005); the data used were of 15 days duration andwere analysed using both the appropriate SEPA hydrographic excel template for 20 minutedata and the hg-analysis spreadsheet, also provided by SEPA. The Admiralty HydrographicOffice tide prediction software Total Tide was used to determine the start dates of spring andneap tides and to determine the times of high water and mean tidal height for the area (seeTable 3).

Following SEPA guidelines the start points in the current meter record used for modelling arethose closest to midday on the day of the intermediate spring tides and the intermediateneap tides. In the current meter data used, after hourly averaging, the times of intermediateHW spring and HW neap corresponded to records 94 and 289 respectively. Prior tocommencement of modelling the current data required correction to Grid North and was thuscorrected by 4.029W. The hourly averaged current data for the surface, middle and bottombins were then saved as space delimited files, as detailed in AMMR11v02 and following thedefault AutoDepomod file structure.

Using the hg-analysis spreadsheet the mean speed and the residual current speed anddirection were established for each of the three current meter depths. The mean and residualcurrents, and the histogram frequency peaks are summarised in Table 2 below. The datashowed a predominant current in a north-westerly direction at near-surface and mid depths. Whereas slower data recorded near-bed showed a north-easterly direction. A slightcorrelation was found between the surface current speeds and the wind speeds (Figure 2); however a tidal pattern can still be seen. The mean wind speed over this period was 4.0m/s.


4

Figure 2 Site current direction frequency from the surface current meter

Site: Scalpay_ subs_ 32.7m_bin24determinetidal ellipse major axis

0000

0020

0040

0060

0080

0100

0120000 010020 030040 050060 070080

090100 110120 130140 150160 170180 190200

210220

230240

250260

270280 290300 310320 330340 350Frequency Of

Readings In Bin Percentage Of CurrentSpeeds In Bin (%)Navigation 100% SURFACEMean Speed m/s 0.068

Residual Speed m/s 0. 040 Residual

Parallelm/s0.032 Residual Normalm/s - 0.

024

Tidal Amplitude Parallel m/ s0.080 Tidal Amplitude Normal m/s0.055 Frequency

Peak

330 MIDDLE Mean Speed m/s0.060 Residual Speed m/s0.034 Frequency

Peak 320 BOTTOM Mean Speed m/s0.053 Residual Speed m/s0.


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2.2 SITE DETAILS

The proposed site is situated near the south-eastern shore of the Isle of Scalpay ( Figure 1). Marine Harvest proposes to install equipment and operate a maximum biomass of 2,500t atthe new site and so the AutoDepomod and the Bath Treatment models have been run todetermine EQS-compliant biomass and medicinal consents for this new equipment. Detailsof the site are provided in Table 3. The receiving water is defined as open water.

Table 3 Project Information

SITE DETAILS

Site Name: ScalpaySite location: Isle of Scalpay, near the Isle of Skye

Peak biomass (T): 2,500Proposed feed load (T/yr): 6,387.5

Proposed treatment use: Azamethiphos, Cypermethrin, Deltamethrin & Emamectin Benzoate

CAGE DETAILS

Group location: 164153E, 828507N; 164153E, 828816NNumber of cages: 12Cage dimensions: 120m circumference

Working Depth (m): 12Cage group configuration: 2(2x3)

Cage group orientation (° G): 0 Cage group distance to shore (km): 0.60

Water depth at site (m): 35

HYDROGRAPHIC DATA

Current meter position: 164082E, 828634NDepth at deployment position (m): 37.8

Surface bin centre height above bed (m): 32.7Middle bin centre height above bed (m): 25.7Bottom bin centre height above bed (m): 2.7

Duration of record: 10/11/13 13:55 to 25/11/13 13:55Current meter averaging interval: 20 min

ADDITIONAL DATA

Magnetic correction to grid North: - 4.029Predicted Spring Tide 11/11/2016Predicted Neap Tide 18/11/2016Predicted Spring Tide 26/11/2016

Mean Tidal Level at Site (m): 3.15Closest Standard Port Broadford Bay

Date of Intermediate- Spring Tides: 14/11/2016Date of Intermediate- Neap Tides: 22/11/2016


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2.3 RUN DETAILS

A new project was created in AutoDepomod and named Scalpay16 vF1. The site and cagedetails provided in Table 3 were entered into the appropriate files and all other data were setto default. The resulting site bathymetry and cage layout is shown in Figure 3. Modelling ofboth the biomass and chemotherapeutants was undertaken following the methods outlined inthe Methods Report AMMR11v02 which is held centrally by SEPA. Details of the modellingresults have been provided in the next section according to SEPA requirements.

Figure 3 bathymetry and cage layout

Two types of treatment are used to control sea lice infestation in marine salmon farms andthese require different modelling approaches. The in-feed treatment Slice (active ingredientEmamectin Benzoate) requires deposition modelling using AutoDepomod to predict thechemical accumulation on the seabed beneath the fish cages associated with fish faeces anduneaten treated feed. The bath treatments Salmosan ( chemical name Azamethiphos), Excischemical name Cypermethrin) and Alphamax ( Deltamethrin), where the salmon are

immersed in a diluted solution of the treatment chemical require dispersion modelling topredict the concentration in the water column after release. Results from both AutoDepomodand the Bath model have been provided in the next section.


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3 MODELLING RESULTS

3.1 BIOMASS RESULTS

AutoDepomod was run initially with the company’s preferred stocking density of15.1482kg/m3, and proposed cage layout, using the model’s auto-distribute biomassfunction. The model did not require to iterate to an EQS-complaint solution as a pass wasachieved at this stocking density and pen volume for the resultant maximum allowablebiomass of 2,500 tonnes.

At this biomass the model predicts the 80% solids area to be 101,519m2 while the flux in thisarea is expected to be 1,516g/m2/year. The proposed layout and tonnage results in a benthiccage area of 40,726m2 with a minimum ITI of 1 within the area. The flux in the benthic cagegroup area is predicted to exceed the trigger value (10,000g/m2/year) at 14,438g/m2/year. The benthic sampling area (ITI = 30) is expected to be 148,354.4m2 while the flux inside thisarea will be 191.8g/m2/year. The plotted AutoDepomod output for the passing Int-Spring run2 is shown in Figure 4. A summary with all of this information can be found in Scalpay16vF1_marine_sum_v3.xls and in Table 7 of this report.

Figure 4 Benthic impact for run 2, Int-Spring current data

The mass of solids released in run 2 is estimated to be 1,020,815kg with 92% (937,154kg) predicted to remain within the 1km2 modelling grid, thus 8% (83,661kg) of the input load ispredicted to be transported from the model grid as a result of resuspension. Current datarecorded at the site results in a vector average residual of 0.040m/s at 323°G at the surface, 0.034m/s at 310°G at the middle, and 0.018m/s at 86°G. Figure 4 shows the dispersal ofwaste material in a northerly direction.


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3.1.1 TRANSECT AND SAMPLING STATIONS

Two transect profiles were created ( Figure 4) as part of SEPA’s requirements to determinesite-specific sampling locations. The selected and spare transect information have beensaved to the Scalpay 16vF1-BcnstFI-S-2_000.xls file located in the mapping folder. Details ofboth transect starting points are provided in Table 4 below.

Figure 4 Location of the selected and spare transects

Transect X1 Y1 X2 Y2 Bearing Length Depth

T1 164150 828984 164135 829205 356.3 220.9 35.5

T2 164155 828489 164162 828256 178.3 232.9 36.9

Table 4 Selected and Spare Transect Starting Points


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Table 5 describe the location and details of the three selected and spare survey stations. Figure 5 shows the cross-sections of the selected and spare transects, and the relevantsurvey stations.

SELECTED

EQS - 10m1st

Station) S1

EQS2nd

Station) S2

EQS + 10m3rd

Station) S3 SPARE

EQS - 10m1st

Station) S1

EQS2nd

Station) S2

EQS + 10m3rd

Station) S3

NGR Easting 164141.2 164140.6 164139.9 NGR Easting 164156.6 164156.9 164157.2

NGR Northing 829113.5 829123.5 829133.5 NGR Northing 828431.2 828421.2 828411.2

Distance ( m) 129.4 139.4 149.4 Distance (m) 57.5 67.5 77.5

CD depth (m) 45.4 45.1 44.9 CD depth (m) 35.3 35.1 34.9

Modelled ITI 28.1 30 32.5 Modelled ITI 24 30 36.5

Table 5a&b The details of the three selected and spare survey stations respectively

Figure 5 Cross-sections of both the selected and spare transects respectively


10

3.2 IN-FEED TREATMENTS

3.2.1 SLICE

The SLICE aspect of AutoDepomod was run initially for a Total Allowable Quantity sufficientto treat 5 times the proposed peak biomass (4,375g & 12,500 tonnes respectively). MarineHarvest have followed SEPA’s guidance and used a feedload of 6387.5T derived from thedefault feed figure automatically generated in the Biomass Section of AutoDepomod. Themodel did not require to iterate to an EQS-complaint solution as a pass was achieved at thisquantity and biomass. The predicted area inside the 0.763 g/kg contour (208,797m2) wassmaller than the predicted far field AZE area (213,248m2). The mean concentration of Slicein the near field AZE exceeds the EQS trigger value of 7.63g/kg by 289.7g/kg and thusenhanced monitoring will be required at the site if Slice is used. The plotted AutoDepomodoutput for this run is shown in Figure 6. A further run for 223 days duration was performed toobtain a site residual curve for this biomass.

Figure 6 EmBZ concentrations for run 1 (118 days)

The mass of EmBZ remaining on the bed at the end of run 1 was 2,906g. For Slice, in theabsence of resuspension, 74% or 3,237.5g of the input EmBZ load would remain on theseabed after 118 days. This indicates that a low percentage of the original input load is lostthrough resuspension ( 7.6%). The mass of EmBZ lost from the grid (331.5g) represents anequivalent area of 3.6km2 if it assumed to distribute evenly at the far field EQS concentrationof 0.763g/kg sediment.


11

3.3 BATH MODEL RESULTS

Cage details are given in section 2. The cage treatment depth used for the bath treatmentswas 2m. Using the results from the analysis of the surface current meter data in the shortterm bath treatment model EQS compliance for both Deltamethrin and Cypermethrin at thiscage depth was predicted. EQS compliance for Azamethiphos was predicted at a cage depthof 2m.

Cypermethrin & Deltamethrin Results: Cage Treatment Depth = 2mPermissible Quantity of Cypermethrin = 48.7g; 4.3 cages/3 hoursPermissible Quantity of Deltamethrin = 18.3g; 4 cages/3 hours

Azamethiphos Results: Cage treatment depth = 2mPermissible Quantity of Azamethiphos = 269.3g; 1.2 cages/3 hoursPermissible Quantity of Azamethiphos = 687.7g; 3.0 cages/24 hours

The permissible quantities means that full treatment of the 12 pens at the site, would takeapproximately 3 days to complete.

The bath treatment model files are saved in the folder Scalpay 16vF1\Bath


12

4 RESULTS AND CONCLUSIONS

It is recommended that the biomass and treatment amounts are consented at this site asgiven below in. The results of the modelling performed at this site are given in the file : Scalpay16vF1_marine_sum_v3.xls’ in the Scalpay16vF1 folder.

BENTHIC MODELLING:

Max fish biomass proposed (T) 2,500

Cage depth (m) 12Max Average Stocking Density (kg/m³) 15.1482

Maximum number of cages 12

loss of solids from model grid (%) 8

Cage area equivalent (m²) 40,726Flux in the cage area (g/m²/y) 14,438

ITI in the cage area 1

Flux under cages exceeds the trigger value

80% solids area (m²) 101,519

Flux in the 80% solids area (g/m²/y) 1,516ITI in the 80% solids area 10.2

Benthic sampling area (m²) 148,354.4

Flux in the benthic sampling area (g/m²/y) 191.8ITI in benthic sampling area 30

SITE SPECIFIC SAMPLING:

Transect start coordinates 164150, 828984

Direction ( T) 356.3

CD Depth (m) 35.5


SPARE TRANSECT INFORMATION

Transect start coordinates 164155, 828489

Direction ( T) 178.3

CD Depth (m) 36.9


IN-FEED TREATMENTS

Peak fish biomass at site (T) 2,500

Near Field AZE (m²) 68,887

Far Field AZE (m²) 213,248

Recommended consent mass EmBZ (g) 4,375

Equivalent Fish Biomass (T) 12,500

Maximum Treatment Amount EmBZ (g) 875

Area of Impact at Far Field EQS (m2) 208,797loss of EmBZ from model grid (% 7.6


13

BATH TREATMENTSRecommended consent mass in 3hrs

Azamethiphos269.3g cage/treatment, 1.2

treatments/ day

Recommended consent mass in 24 hrsAzamethiphos

687.7g cage/treatment, 3treatments/ day

Recommended consent mass in 3 hrsCypermethrin

48.7g cages/treatment, 4.3treatments/ day

Recommended consent mass in 3 hrsDeltamethrin

18.3g cages/treatment, 4treatments/day

Table 6 Modelling Results Summarised


14

REFERENCES

SEPA 2005. Regulation and monitoring of marine cage fish farming in Scotland - aprocedures manual: Annex G – Models for assessing the use of medicines in bathtreatments (January 2007).

SEPA, 2005. Regulation and monitoring of marine cage fish farming in Scotland - aprocedures manual: Annex H - Methods for Modelling In-Feed Anti-Parasitics and BenthicEffects (June 2005)

SEPA, 2005. Regulation and monitoring of marine cage fish farming in Scotland - aprocedures manual: Attachment VIII – Hydrographic data requirements for applications todischarge from Marine Cage Fish Farm (May 2005).

UKHO, 2002. Admiralty Tide Tables; volume 1 UK and Ireland. United KingdomHydrographic Office, Taunton.

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