Biomass and Chemotherapeutant
Total Page:16
File Type:pdf, Size:1020Kb
BIOMASS AND CHEMOTHERAPEUTANT TECHNICAL MODELLING REPORT CAR/ L/ 1016128 COPISTER Author: Vicki Smith Report date: 11 October 2017 Cooke Aquaculture Scotland Crowness Rd, Hatston Industrial Estate, Kirkwall, Orkney, KW15 1RG T: +44 (0)1856 876101 www.cookeaqua .com Copister Technical Modelling Report October 11, 2017 Table of Contents 1. Summary ........................................................................................................ 2 2. Introduction ................................................................................................... 3 3. Input data ...................................................................................................... 4 3.1 Site data .................................................................................................... 4 3.2 Hydrographic data .................................................................................... 5 3.3 Bathymetric data ...................................................................................... 6 3.4 Bath modelling .......................................................................................... 7 4. Results ........................................................................................................... 8 4.1 Biomass ..................................................................................................... 8 4.1.1 Transects and sampling stations ......................................................... 9 4.1.2 Fate Assessment of Exported Material ..............................................12 4.2 In-feed treatments .................................................................................. 15 4.2.1 Slice – Emamectin Benzoate ............................................................. 15 4.3 Bath treatments ...................................................................................... 20 4.3.1 Salmosan Vet – Azamethiphos .......................................................... 20 4.3.2 Excis - Cypermethrin ......................................................................... 21 4.3.3 Alphamax - Deltamethrin .................................................................. 21 4.3.4 Alternative bath models .................................................................... 21 5. Discussion .................................................................................................... 22 6. References ................................................................................................... 24 7. Appendices .................................................................................................. 25 7.1 Appendix 1 - Changeover to Salmosan Vet.............................................. 25 Cooke Aquaculture Scotland Page 1 | 26 Copister Technical Modelling Report October 11, 2017 1. Summary Cooke Aquaculture Scotland Ltd . (CAS) has undertaken biomass and chemotherapeutant modelling work for the marine cage fish farm site, Copister. The site is located in Hamna Voe situated off the south coast of the island of Yell, Shetland. The proposed new set up at the Copister site is 16x120m circular cages, split into two 4x2 cage groups with a separation distance of 60m. The site was modelled to determine the maximum biomass and the recommended consent limits of in-feed treatments and bath treatments in regards to the new infrastructure being proposed. Site specific benthic monitoring transects were defined with a primary sampling transect originating from the south west cage on the southern cage group on a bearing of 134°G. The recommended consent limits achieved are detailed in Table 1. Table 1 Summary of the Recommended Consent Limits for the Copister site. Maximum Biomass 2,486.5t Stocking density 11.3kg/ m3 In-Feed Treatments Emamectin Benzoate TAQ MTQ Mass (g) 4,351.4 870.3 Equivalent Treatable 12,432.5 2,486.5 Biomass ( t) Bath treatments Azamethiphos Cypermethrin Deltamethrin 3hr 24hr 3hr 3hr Mass (g) 279.1 214.3 50.52 18.95 Equivalent Treatable 2,791 2,143 10,104 9,473 Volume (m3) Cooke Aquaculture Scotland Page 2 | 26 Copister Technical Modelling Report October 11, 2017 2. Introduction The proposed changes to the Copister site include an increase in cage number and cage size from 10x100m circumference cages to 16x120m circumference cages. The cages will be split into two groups of eight cages arranged in 4x2 grid configurations with a 60m separation distance between the groups. The cages groups run parallel to the eastern coastline of Hamna Voe, orientated to 320°. The cages will be housed in 60m square grids with a net depth of 12m. The site centre located between the two cage groups is 60°29.422’N 01°05.071’W (HU 50407 78868). Figure 1 illustrates the location of the Copister site. The proposed new set up at the Copister fish farm has been modelled to determine the maximum permissible biomass at the site and to produce a monitoring protocol recommendation for submission to SEPA. In addition , the quantities of the in-feed treatment Slice and the bath treatments Salmosan Vet, Excis and Alphamax are to be determined ensuring they are compliant with the required standards set by SEPA under The Water Environment ( Controlled Activities) ( Scotland) Regulations 2011 (CAR). Figure 1 Site location Cooke Aquaculture Scotland Page 3 | 26 Copister Technical Modelling Report October 11, 2017 3. Input data 3.1 Site data AutoDepomod version 2.0.52 is used to simulate the release and deposition of waste feed and faecal material on the seabed from which the benthic impact is predicted. For in-feed treatments the area and concentration of chem ical deposition are derived via simulation of the chemical load associated with this material. Residual discharge concentrations are calculated using aqueous discharge models for bath treatments (BathAuto version 5.1). The distance to shore parameter is taken as the distance from the site centre located between the two cage groups to the nearest shoreline on Yell to the east. The average water depth is determined from the AutoDepomod bathymetry grid file utilising the Surfer volume calculations. Background information on the techniques employed are detailed in a separate methods report ‘Biomass and Chemotherapeutant Modelling Methods Report’ which can be found on the USB flash drive. Site specific data for the Copister site required by AutoDepomod are presented in Table 2. Table 2 Site Input Data Site name Copister Consent Number CAR/ L/ 1016128 Company Cooke Aquaculture Scotland Receiving water Hamna Voe Site NGR 450407 1178868 Current meter NGR 450342 1178985 Distance to shore (km) 0.488 Average water depth (m) 22.71 Number of cages 16 Shape of cages Circular Circumference of cages (m) 120 (Radius – 19.1m) Cage group configuration 2 groups-4x2 Grid size (m2) 60 Cage group orientation (°Grid) 320 Working net depth (m) 12 Treatment net depth (m) 2.43 Cooke Aquaculture Scotland Page 4 | 26 Copister Technical Modelling Report October 11, 2017 3.2 Hydrographic data A hydrographic survey at the Copister site was carried out in November and December 2010. The data and report was accepted by SEPA as being suitable for modelling purposes. A 15 day subset of data was selected running from 17th November to 2nd December 2010 using data from three specified depths that represented near surface, cage bottom and near seabed layers. Direction data are supplied pre-corrected to Grid North. Intermediate spring and neap tides were identified from tidal heights for Burra Voe. Raw current velocity data was formatted for use in AutoDepomod using the SEPA template ‘ temp-20min-HGv3.xls’ files created ‘Copister-HG.xls’, ‘ Copister-NS-b.dat’, ‘Copister-NS-m.dat’, ‘Copister-NS-s.dat’). The hydrographic input data is shown in Table 3 below: Table 3 Hydrographic Data Input Depth of current meter (m) 24.6 Height of surface cell from the seabed (m) 20 Height of middle cell from the seabed ( m) 16.6 Height of bottom cell from the seabed (m) 3 Date Spring Tide commence 18/ 11/ 2010 06:40 Data record number) 25) Date Neap Tide commence 25/ 11/ 2010 06:40 Data record number) 193) Current Speed unit cm/ s Mean Sea Level (m)* 1.35 Compass variation 0.0W Source:* Admiralty TotalTide Version 17,0,0,5 - Nearest port: Burra Voe Cooke Aquaculture Scotland Page 5 | 26 Copister Technical Modelling Report October 11, 2017 3.3 Bathymetric data Bathymetry data was derived by digitising contours and spot depths from an Admiralty Chart. The data was re-contoured using Surfer 8. Data was limited to a 1km² model domain with the grid limits: Minimum – 449840 1178340 Maximum – 450840 1179340 Bathymetric data files were created; ‘Copister.csv’, ‘ Copister.bln’ and ‘Copister.ini’. Figure 2 below shows the bathymetry of the 1km2 model grid and the location of the Copister cage groups. 1179200 1179000 1178800 1178600 1178400 450000 450200 450400 450600 450800 Eastings Admiralty charts: Copyright: © Crown Copyright/ SeaZone Solutions. All Rights Reserved. Licence No. 052006. 001 (2017). NOT TO BE USED FOR NAVIGATION. Figure 2 Bathymetry of the model grid illustrating the location of the cage groups. Cooke Aquaculture Scotland Page 6 | 26 Copister Technical Modelling Report October 11, 2017 3.4 Bath modelling For the long term bath treatment model the “ strait” scenario was considered as the most appropriate to the site location. For the input parameters, the strait which was outlined as the south section of Yell Sound was defined by the following boundaries; at the north mouth between Mio Ness, mainland Shetland (HU 42670 79283) and Clothan, Yell (HU 45573