1.7.3 Marine Mammal Observers

  1. There will be two dedicated marine mammal observers responsible for monitoring the mitigation zones and conducting searches prior to piling, UXO detonation and/or soft start procedures, and geophysical surveys. They will report to the ECoW and will be responsible for conducting the 15-minute post-detonation search as part of the UXO clearance protocol. They will be appropriately trained: have completed the JNCC registered marine mammal observer course and have sufficient field experience (at least one year of marine mammal observers experience on offshore projects).
  2. They will be positioned on a suitable platform on a vessel that allows full 360° coverage of the mitigation zone and an observer eye height of at least 5 m. They will be equipped with appropriate visual aids (such as reticule binoculars) and will be capable of determining the extent of the various mitigation zones depending on the survey. They will be responsible for recording any marine mammal observations using Marine Mammal Recording Forms provided by JNCC.

1.7.4 PAM Operator

  1. There will be one dedicated PAM Operator who will be responsible for acoustically tracking vocalising marine mammals using a hydrophone, via the computer software PAMGuard. They will report to the ECoW and will also be responsible for deploying and maintaining the hydrophone and any spares. They will be appropriately trained and have sufficient field experience (at least one year of PAM experience on offshore projects).
  2. They will operate from the same vessel as the marine mammal observers and will collaborate with the marine mammal observers to compile all the data on mitigation activities and observations. They will also be responsible for using PAMGuard to confirm that the ADD is functioning correctly and communicating with the ADD operator if it is not.

1.7.5 ADD Operator

  1. There will be one ADD Operator responsible for deploying, maintaining, and operating the ADDs and any spares, with the requirements outlined in this outline MMMP. They will report to the ECoW and will be required to communicate clearly with marine mammal observers, PAM Operator and, in the case of UXO disposal, the EOD Supervisor, to confirm commencement and cessation of ADD usage. They will also be required to communicate with the PAM Operator to check that ADDs are functioning correctly.
  2. The ADD Operator will also be responsible for providing final report(s) on ADD usage during the UXO clearance excursions.

1.7.6 EOD Supervisor

  1. An EOD Supervisor will be required during UXO clearance activities to ensure that the requirements of the outline MMMP are met. They will report to the ECoW and will be responsible for decisions involving initiating, delaying or pausing detonation and ensuring that no UXO detonation occurs without their explicit consent. They must ensure clear lines of communication between the ECoW, marine mammal observers, PAM Operator, ADD Operator and EOD contractors.

1.8. Reporting

  1. The ECoW will be responsible for monitoring piling, UXO clearance and geophysical surveys and implementation of the outline MMMP and will keep a detailed record of operations, mitigation procedures and any marine mammal sightings. These records will be prepared and submitted in compliance with consent and/or license conditions to MD-LOT and will include completing and submitting Marine Mammal Recording Forms provided by the JNCC.

1.8.1 Piling

  1. Reporting will include a record of the following:
  • date and location of piling operations;
  • a record of all occasions when piling occurred, including details of the duration of the pre-piling search and soft-start procedures, and any occasions when piling activity was stopped or delayed due to the presence of marine mammals;
  • presence, location, and activity of vessels during piling procedures;
  • the mitigation procedures followed for each piling event, including details of marine mammal observer activities, PAM operation, ADD duration and size and timing of soft-start charges where required;
  • details of PAM equipment and ADDs used and any relevant observations on their efficacy;
  • all marine mammal sightings and mitigation taken and completed JNCC marine mammal recording forms;
  • detailed descriptions of any technical problems encountered and what, if any, actions were taken;
  • any problems encountered and instances of non-compliances with the JNCC guidelines (2010a), outline MMMP, and variations from agreed procedures; and
  • protocols followed and put forward any recommendations based on the project and any marine mammal sightings/behaviour encountered during the piling operations which could benefit future projects.

1.8.2 UXO Clearance

  1. Reporting will include a record of the following:
  • identification of all confirmed UXO, including estimated size, type, location and depth;
  • approach taken for each UXO, including dates, times, disposal method attempted (based on size and type, and number of donor charge(s) used);
  • details of any UXOs relocated or if any UXOs larger than 698 kg are identified;
  • presence, location, and activity of vessels during UXO clearance;
  • outcome of each UXO clearance, including evidence of high-order detonation, clearing charges required, and method of debris and residue recovery;
  • the mitigation procedures followed for each UXO clearance, including details of marine mammal observers activities, PAM operation, ADD duration and size and timing of soft-start charges where required;
  • details of PAM equipment and ADDs used and any relevant observations on their efficacy;
  • all marine mammal sightings and mitigation taken and completed JNCC marine mammal recording forms;
  • detailed descriptions of any technical problems encountered and what, if any, actions were taken;
  • any problems encountered and instances of non-compliance with the JNCC guidelines (2010b), outline MMMP, and variations from agreed procedures; and
  • protocols followed and put forward any recommendations based on the project and any marine mammal sightings/behaviour encountered during the UXO operations which could benefit future projects.

1.8.3 Geophysical Surveying

  1. Reporting will include a record of the following:
  • approach taken for each geophysical survey, including dates, times, survey type, equipment used, and coordinates and transects of surveys;
  • presence, location, and activity of vessels during geophysical surveying;
  • a summary of the marine mammal observers and PAM activities, including specifics of the conducted surveys and any relevant observations on the efficacy of PAM equipment;
  • all marine mammal sightings and mitigation taken and completed JNCC marine mammal recording forms;
  • detailed descriptions of any technical problems encountered and what, if any, actions were taken;
  • any problems encountered and instances of non-compliances with the JNCC guidelines (2017), outline MMMP, and variations from agreed procedures; and
  • protocols followed and put forward any recommendations based on the project and any marine mammal sightings/behaviour encountered during the geophysical surveying operations which could benefit future projects.


1.9. References

Bailey, H. and Thompson, P. (2010). Effect of oceanographic features on fine-scale foraging movements of bottlenose dolphins. Marine Ecology Progress Series, 418, pp.223-233.

Boisseau, O., McGarry, T., Stephenson, S., Compton, R., Cucknell, A. C., Ryan, C., McLanaghan, R. and Moscrop, A. (2021). Minke whales Balaenoptera acutorostrata avoid a 15 kHz acoustic deterrent device (ADD). Marine Ecology Progress Series, 667, 191-206.

JNCC (2010a). Statutory nature conservation agency protocol for minimising the risk of injury to marine mammals from piling noise. August 2010. Available at: Statutory nature conservation agency protocol for minimising the ris of injury to marine mammals from piling noise (jncc.gov.uk). Accessed on: 18 April 2024.

JNCC (2010b). JNCC guidelines for minimising the risk of injury to marine mammals from using explosives. Joint Nature Conservation Committee, Aberdeen, UK.

JNCC (2017). JNCC guidelines for minimising the risk of injury to marine mammals from geophysical surveys. Joint Nature Conservation Committee, Aberdeen, UK.

McGarry, T., De Silva, R., Canning, S., Mendes, S., Prior, A., Stephenson, S. and Wilson, J. (2020). Evidence base for application of acoustic deterrent devices (ADDs) as marine mammal mitigation (Version 2.0). JNCC Report No. 615, JNCC, Peterborough. ISSN 0963-8091.

Robinson, S. P., Wang, L., Cheong, S., Lepper, P.A., Marubini, F. and Hartley, J. P. (2020). Underwater acoustic characterisation of unexploded ordnance disposal using deflagration. Marine Pollution Bulletin, Volume 160, 111646, ISSN 0025-326X.

Seagreen Wind Energy (2021). Seagreen Alpha and Bravo Site UXO Clearance – European Protected Species Risk Assessment and Marine Mammal Mitigation Plan.

Southall, B. L., Finneran, J. J., Reichmuth, C., Nachtigall, P. E., Ketten, D. R., Bowles, A. E., Ellison, W. T., Nowacek, D. P. and Tyack, P. L. (2019). Marine Mammal Noise Exposure Criteria: Updated Scientific Recommendations for Residual Hearing Effects. Aquatic Mammals, 45 (2), pp.125-232. DOI:10.1578/am.45.2.2019.125

Thompson, D. (2015). Parameters for collision risk models. Report by Sea Mammal Research Unit, University of St Andrews, for Scottish Natural Heritage.

UK Government, Department for Business, E. a. I. S. B., Marine Management Organisation (MMO), Joint Nature Conservation Committee (JNCC), Natural England (NE), Offshore Petroleum Regulator for Environment and Decommissioning (OPRED), Department of Agriculture, E. a. R. A. D., NatureScot, Marine Scotland and Natural Resources Wales. (2022). Marine environment: unexploded ordnance clearance joint interim position statement. Available at: https://www.gov.uk/government/publications/marine-environment-unexploded-ordnance-clearance-jointinterim-position-statement/marine-environment-unexploded-ordnance-clearance-joint-interim-position-statement. Accessed on: 03 June 2023.

Von Benda-Beckmann, A.M., Aarts, G., Sertlek, H.Ö., Lucke, K., Verboom, W.C., Kastelein, R.A., Ketten, D.R., van Bemmelen, R., Lam, F.P.A., Kirkwood, R.J. and Ainslie, M.A. (2015). Assessing the impact of underwater clearance of unexploded ordnance on harbour porpoises (Phocoena phocoena) in the Southern North Sea. Aquatic Mammals, 41(4), 503.