Impacts on the Receiving Environment. Proposed Dredging and Dumping at Sea Operations Fenit Co Kerry
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Impacts on the receiving Environment. Proposed dredging and Dumping at Sea Operations Fenit Co Kerry Impacts on the receiving 14996 March 2015 environment ISSUE FORM Project number 14996 Document number 14996 - 1 Document revision A Document title Impacts on the receiving Environment. Proposed dredging and Dumping at Sea Operations Fenit Co Kerry Document status Final Document prepared by Ken Fitzgerald Document checked by Sean Doyle i Impacts on the receiving 14996 March 2015 environment Table of contents 1 IMPACTS ON THE RECEIVING ENVIRONMENT. ............................................................ 1 2 DREDGE LOCATION WITHIN FENIT HARBOUR. ............................................................ 1 2.1 Site location and description ............................................................................................. 1 2.2 Existing Environment ........................................................................................................ 3 2.2.1 Bedrock geology and coastline to the north ......................................................................................... 3 2.2.2 Bathymetry ............................................................................................................................................ 3 2.2.3 Marine Sediments ................................................................................................................................. 3 2.2.4 Benthic Ecology ..................................................................................................................................... 4 2.3 Proposed dredging ............................................................................................................ 4 2.4 Potential Environmental Impacts ....................................................................................... 5 2.4.1 Loss and alteration of seabed habitat ................................................................................................... 6 2.4.2 Water quality impacts from increased suspended sediment and turbidity levels in the water column at the dredge site ............................................................................................................................................... 6 2.4.3 Disturbance to species through smothering from the deposition of suspended solids ....................... 7 2.4.4 Temporary noise disturbance from dredging plant .............................................................................. 7 2.4.5 Water quality impacts from accidental oil spill associated with fuelling activities of the suction hopper dredger .................................................................................................................................................. 7 3 PROPOSED DUMPING AT SEA SITE ............................................................................. 7 3.1 Site location and description ............................................................................................. 7 3.2 EXISTING ENVIRONMENT .................................................................................................. 8 3.2.1 Bedrock geology .................................................................................................................................... 8 3.2.2 Bathymetry ............................................................................................................................................ 8 3.2.3 Marine Sediments ................................................................................................................................. 8 3.2.4 Benthic Ecology ..................................................................................................................................... 8 3.3 Potential Environmental Impacts ....................................................................................... 8 3.3.1 Loss and alteration of seabed habitat ................................................................................................... 9 3.3.2 Water quality impacts from increased suspended sediment and turbidity levels in the water column at the dredge site ............................................................................................................................................... 9 3.3.3 Disturbance to species through smothering from the deposition of suspended solids ..................... 10 3.3.4 Temporary noise disturbance from dredging plant ............................................................................ 10 3.3.5 Archaeology ........................................................................................................................................ 10 4 DISCUSSION ............................................................................................................. 10 ii Impacts on the receiving 14996 March 2015 environment 1 IMPACTS ON THE RECEIVING ENVIRONMENT. This section addresses the potential impacts on the environment related to the dredging operations and the dumping at sea activities. It is informed by the following reports which are also included in the application documentation. Natura Impact Statement (NIS) by Malachy Walsh & Partners. Fenit Harbour Dredge Disposal Site – Sediment Transport Model by Aquafact . Fenit Harbour & Proposed Dumpsite Baseline Characterisation Report by Aquafact . Underwater Archaeological Impact Assessment by Lar Dunne Archaeology . Dump site selection report . Review of existing reports and records . Discussions with stakeholders . Bathymetry mapping by Hydrographic Surveys Ltd The report is set out in two sections. The first section deals with the dredge location and the second with the dumpsite location. 2 DREDGE LOCATION WITHIN FENIT HARBOUR. 2.1 SITE LOCATION AND DESCRIPTION The site is located on the west coast of Ireland, in County Kerry on the northern side of Tralee Bay. The bay is sheltered from the Atlantic by the Maharee tombolo, which extends northwards from the Dingle Peninsula. Fenit Harbour and Marina is located about 10km west of Tralee Town, just south of the mouth of the Shannon Estuary (Lat 52°16’N Long 9°52’W). The village of Fenit lies north of the harbour. A location map of the site is presented in Figure 1 below. A 400 m long causeway and viaduct connects the site to the village. The footprint of the existing harbour and marina is 7ha. From the viaduct the fishing quays stretch south to the rocky outcrop that is Samphire Island and turn east to the newer commercial shipping quays and spur/spring pier. The marina area is located within the shelter of the rubble mound breakwater to the northeast of the site. The location of the harbour and proposed dumpsite can be seen in Figure 1 below. Figure 1. Location of Fenit Harbour (dredge location), and proposed dumping at sea site. 1 Impacts on the receiving 14996 March 2015 environment Fenit is the most westerly commercial port in Ireland and is the only commercial port between Foynes and Cork. It is used for commercial shipping, servicing a domestic fishing fleet, leisure and amenity and lifesaving. The main deep sea pier is 175m long with extensive storage facilities available. The landing quays have a design dredge depth of -7.5mCD. Fenit Harbour is an important logistical base for the Killarney based Liebherr cranes. The commercial shipping quays facilitate 15,000 tonne ships of container cranes of a frequency of approximately 15 to 20 per annum. Currently, the fishing fleet operating out of Fenit include approximately 1 large trawler, 2 medium trawlers and 24 half decker trawlers in addition to a number of charter sea angling vessels. Fenit Marina was built in 1997 and has a 130 berth marina and caters to leisure craft from 6m to 15m in length. It has a plan area of approximately 1.5ha. The marina has a design dredge depth of -3.5mCD. The existing marina berths facilitate leisure craft during the peak summer months and a mixture of both fishing and leisure in the off-season. Land use in the vicinity of the harbour on the mainland includes agricultural, recreational, residential, commercial and open space. The harbour is approximately 500m south of Fenit village. The land directly to the north of the proposed expansion is primarily amenity, residential and open space. The Fenit blue flag beach is located to the northwest of the site and is an important amenity area for the local community. A further stony beach is located to the northeast of the site. The proposed maintenance dredging will take place within the commercial shipping berth and at the manoeuvring area as can be seen in Figure 2 below. Figure 2. Location of dredging within Fenit Harbour. 2 Impacts on the receiving 14996 March 2015 environment 2.2 EXISTING ENVIRONMENT 2.2.1 Bedrock geology and coastline to the north Fenit Harbour is situated on the northern shore of Tralee Bay, north of the Dingle Peninsula. According to Geological Survey of Ireland (GSI) mapping and supporting data the Dingle Peninsula which makes up the southern shore of the bay is a syncline of Devonian Sandstone with Namurian Sandstone on its flanks. In addition, the GSI map indicates that Tralee Bay is underlain with Carboniferous Limestone as is the Tralee area with the hills to the west consisting of Namurian sandstone. The Carboniferous Limestone outcrops within the harbour at Samphire Island. Geotechnical investigations undertaken in 1996 indicate that the rock dips away under the surrounding overburden which forms the bed of the harbour and nearby area. The existing harbour was