Newlands Cross Upgrade EIS - European Investment Bank

More documents

Recommendations

Info

South Dublin County Council N7 Newlands Cross Upgrade Environmental Impact Statement Arup Consulting Engineers Carriageway Drainage and Outfalls Due to the urban nature of Newlands Cross, a closed drainage system is being utilised. All rainfall runoff will be prevented from discharging to the surrounding lands by kerbs, will be collected by gullies, and conveyed by carrier pipes. The runoff will only outfall at specified outfall locations. Oil / petrol Interceptors will be installed at each outfall, to prevent oil from entering the receiving watercourses. 14.4.3.2 Water Quality Introduction The quality of surface water resources in proximity to the upgraded junction may be impacted by a number of different sources: • Road Runoff: routine road runoff generally contains a variety of contaminants. These arise from the degradation of the road surface and vehicles, vehicle exhaust combustion by-products, soil erosion and aerial deposition. The primary contaminants known to occur in routine road runoff include hydrocarbons, particulate matter and heavy metals. • Winter Maintenance: the application of salt to the road surface to prevent icy conditions developing can lead to increased electrical conductivities in the receiving watercourse following application. • Accidental Spillage: spillages arising from accidents involving goods transportation are potentially the most serious source of contaminants to a watercourse from a road. These potential sources are discusses in greater detail below. Road Runoff Contaminants arising from road runoff regarded as having the greatest potential to adversely affect aquatic ecosystems include suspended solids, hydrocarbons and heavy metals. The primary hydrocarbons of concern are the petrochemical derived group which includes petrol, fuel oils, lubricating oils and hydraulic fluids. These are generally liquid and water insoluble. A wide range of heavy metals are known to occur in road runoff, but the primary metals of concern are cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) (Birch & Taylor, 1999) 10 . All of these metals are included in the EU Dangerous Substances Directive (76/464/EEC) 11 and the proposed EU Priority Contaminating Substances Directive which forms an annex addition to the Water Framework Directive 12 . Cd is included on the EU blacklist of dangerous substances, and as such its uses are now restricted. This has led to a considerable decrease in concentrations of Cd in road runoff. The concentration of Pb is also reducing in road runoff due to the substantial reduction of Pb as a fuel additive since the mid 1980’s. Pb has limited solubility (between 1 – 10%), so that the majority of Pb in road runoff is bound to particulate matter. Cu and Zn are used widely in the automotive industry, and are moderately soluble in water (Kennish, 1995) 13 . Sediments are the dominant mass of pollutants from road runoff. While most of the sediment load is chemically inert, the increase in turbidity of a watercourse has detrimental impacts on the aquatic system’s quality. The sediment load also acts as the primary transport mechanism for contaminants in the water column, contaminants bind to sulphides and organic matter particles that form suspended colloidal particles. Bound together in this fashion contaminants have the potential to become bioavailable (Luoma, 1990 14 ). The main sources of pollution in routine road runoff are vehicular in origin. However, studies have shown no clear correlation between traffic volumes and runoff quality. The magnitude of the impact also depends largely on the value and the sensitivity of the receiving watercourse. As the proposed project is an upgrading of the existing junction there will be an increase in December 2007 Page 229
South Dublin County Council N7 Newlands Cross Upgrade Environmental Impact Statement Arup Consulting Engineers hard surface areas and an increased volume of traffic using the new interchange. This will lead to an increased risk of pollution to the local watercourse. Winter Maintenance Salt applications to road surfaces to mitigate against icy conditions, will result in an increased salinity, pH, conductivity and total dissolved solids concentrations to the receiving aquatic system following application. Salt applications are carried out as part of the winter maintenance programme. Increasing the salinity of the watercourse can adversely affect the ecological balance of the aquatic system and increase the bioavailability of chemical contaminants 13 . The NRA currently operates a winter maintenance programme on the radial routes into Dublin, which is carried out by South Dublin County Council for the N7. The winter maintenance programme is operated in accordance with the NRA guidance notes published in the pamphlet “Ice Monitoring and Winter Maintenance Information and Guidance Notes” 15 . This document outlines the maintenance requirements to maximise road safety during periods of frost and snow, while minimising the application of chemical de-icing agents to the road surface. The winter maintenance programme involved thermal mapping of the radial routes connected to the M50 and the M50 itself in order to predict where icy conditions are likely to develop based on a weather forecast model (ICECAST software). South Dublin County Council has access to the ICECAST software during the winter high-risk period, which predicts the conditions likely to occur at specific locations and allows the determination of the optimum rate of application of salt depending on the conditions predicted. The NRA Guidance Notes recommend an application rate of between 10g/m² (frost/light snow) and 40 g/m² (continuous snow) of salt (NaCl). The ICECAST system is designed to ensure that the application of salt to the road surface is minimised without compromising road safety. Accidental Spillage Potentially the most serious source of contamination to a watercourse associated with roads is an accidental spillage resulting from individual accidents involving transported goods. The proposed junction upgrade incorporates the provision of an emergency containment system, which can be initiated by the emergency services. The pollutant will be directed away from the outfall by a valve mechanism operated by the emergency services and stored in this facility until the emergency services can safely remove it. 14.4.3.3 Aquatic Ecology The impacts on aquatic ecology are specific to each watercourse and are discussed below: Ballymount Park and the Camac River Any pollution arising from the operational phase of the upgraded Newlands Cross Junction would initially flow into the Ballymount Park surface water system and subsequently the Camac River. This could potentially constitute a very minor adverse impact. Pollution from the upgraded junction could pose a very minor adverse impact to the Camac River owing to its high fisheries value. Another potential adverse impact would be concerned with a degradation of water quality which could potentially lead to a degradation of riparian vegetation. This could reduce the aesthetic value of the Ballymount Park surface water features downstream of the upgraded junction. However, the mitigation measures outlined in Section 14.5 will reduce this risk to a minimum. December 2007 Page 230
Page 1 and 2:
Kildare County Council South Dublin
Page 4:
South Dublin County Council N7 Newl
Page 7 and 8:
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
Page 63 and 64:
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
Page 71 and 72:
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
Page 79 and 80:
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
Page 161 and 162:
Page 163 and 164:
Page 165 and 166:
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
Page 175 and 176:
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Page 197 and 198:
Page 199 and 200:
Page 201 and 202:
Page 203 and 204:
Page 205 and 206:
Page 207 and 208:
Page 209 and 210:
Page 211 and 212:
Page 213 and 214:
Page 215 and 216: South Dublin County Council N7 Newl
Page 265: South Dublin County Council N7 Newl
Page 288: PLATES
Page 292: APPENDIX A5 - TRAFFIC AND TRANSPORT
Page 295 and 296: South Dublin County Council Newland
Page 310 and 311: 0 kilometres 2 Scale N.T.S Ordnance
Page 316 and 317:
South Dublin County Council Newland
Page 318 and 319:
Page 320 and 321:
Page 322:
APPENDIX A8 - NOISE AND VIBRATION
Page 326:
APPENDIX A9 - AIR QUALITY
Page 329 and 330:
Page 331 and 332:
Page 334:
APPENDIX A11 - ECOLOGY
Page 337 and 338:
Page 340:
APPENDIX A12 - ARCHAEOLOGY, ARCHITE
Page 343 and 344:
Page 345 and 346:
Page 347 and 348:
Page 349 and 350:
Page 351 and 352:
Page 353 and 354:
Page 355 and 356:
Page 357 and 358:
Page 360 and 361:
Page 362 and 363:
Page 364:
show all

Newlands Cross Upgrade EIS - European Investment Bank

Create successful ePaper yourself

Delete template?

Save as template?