Marine mammal mitigation of blasting at Doolin Pier

26th Jun 2014

26 June 2014

The first blasting took place in Doolin last night with detonation at 21:10 hours. The Marine Mammal Mitigation Plan was successfully delivered by IWDG and no marine mammals were affected. Despite heavy rain, sea conditions were very favourable with seastate 0-1 throughout. Visual and acoustic monitoring 60-150 minutes pre-blast detected no marine mammals or otters and blasting went ahead. Post-blast monitoring recovered two dying pollack which were thought to have been killed by the shock wave but no other affected marine life was observed.

Additional blasting may take place next week.

 

11 June 2014

The proposed blasting at Doolin as part of the pier works has caused some local and media interest. The IWDG have been involved in this planning issue and are contracted to implement a Marine Mammal Mitigation Plan.  Here we provide the background to the project and the plan to be implemented.

The pier extension at Doolin has been talked about for many years and Clare County Council has been processing the planning application for the past 2 years. As part of planning obligations an Environmental Impact Assessment was carried out and put out to public consultation.  IWDG responded as interested stakeholders and Patrick Lyne prepared a document to mitigate the impact of the proposed works, including blasting, on all cetaceans in the area, including "Dusty” the social dolphin that has been in Doolin Harbour for the past 2 years. As part of our submission, IWDG did not accept the proposed impact zone of just 64m, which was extended to 150m as a precautionary measure, recommended by Biospheric Engineering following sound attenuation. IWDG suggested this mitigation zone should be extended and used different mathematical modelling equations to suggest a 500m mitigation zone. This zone should be clear of marine mammals prior to blasting, which was also consistent with NPWS Guidelines. These revised impact zones were included in the IWDG submission to Clare County Council.

Planning has been granted and L&M Keating are the engineering contractors. Aquafact in Galway are the ecological consultants and IWDG have been sub-contracted by L&M Keating to implement the Marine Mammal Mitigation Plan during blasting. Aquafact are responsible for mitigating other aspects of the works on cetaceans and other marine mammals. As part of delivery of this mitigation plan, the IWDG will be using passive acoustic monitoring through a hydrophone deployed at the site and run ashore into a control centre and visual techniques. We will also launch our RIB to patrol the area to ensure no marine mammals are within the mitigation zone of 500m or its vicinity. Fortunately Dusty is currently at Inisheer, around 8km from the blast site so there will be no impact on her.

To our knowledge this is the first marine blasting activity to be authorised since the new NPWS Guidance to Manage the Risk to Marine Mammals from Man-made Sound Sources in Irish Waters published in December 2013. Although we feel the proposed mitigation is sufficient to minimise any impact on marine mammals these mitigation plans must be monitored and assessed to inform future decisions on these marine activities.  

 

Dr Simon Berrow

IWDG Executive Officer

 

L&M Keating have also made the following statement following recent local interest in this marine development

MARINE MAMMALS AT DOOLIN PIER - BLASTING

In early April 2014, L&M Keating Ltd. were awarded the contract of building a new pier at Doolin, Co Clare. Work for this project also commenced in April 2014 and is expected to take in the region of 12 months to complete. As part of the works, blasting will be required in order to create a navigational channel for safe access to the new pier. There have been numerous enquiries into the protection of marine mammals (in particular the resident Bottlenose Dolphin ‘Dusty’) from the proposed blasting and related works. We hope that the information below will clarify the Contractors intentions during the construction phase of this project.

Confined underwater blasting will be used as a construction technique to pre-treat and crack hard rock with minimal impacts. Blasting will be confined to a small areas and techniques such as the use of short inter-charge time delay (of milliseconds in duration) will be employed in order to minimise the cumulative effect of separate individual blast pulses. The Irish Whale and Dolphin Group (IWDG) have designed a site specific Marine Mammal Mitigation Plan and have recommended a 500m mitigation zone around the proposed blast area.  IWDG will be onsite to conduct Passive Acoustic Monitoring (PAM) during all blasting activities. Furthermore, a Marine Mammal Observer (MMO) is full time onsite during all phases of the works.

The blasting will be scheduled if possible to take place within 30 – 60 minutes of the time of Low Water in order to reduce the propagation of harmful sound through the water column.

The MMO(s) and PAM operators will conduct pre-start-up constant effort monitoring at least 60 minutes before the blasting activity is due to commence, continuing monitoring during and after for at least 60 minutes following the activity. If a marine mammal is detected within the Exclusion Zone prior to an intended blasting event, it will not occur.

It is understood that, ‘Dusty’ has been present in the waters around Inis Oírr since early March 2014.  The Contractor will liaise with locals on the island to ensure that ‘Dusty’ is present there before any blast will take place.With the proposed noise and vibration mitigation measures in place no significant long term impact on marine life in the bay is expected.

Regards,

Seán Killeen

 

 

L&M Keating Ltd.
Building & Civil Engineering Contractors

www.lmkeating.ie