813 Technical project description

plant during weekdays, both during the construction phase and normal operation.

3.18 Traffic connections and

power lines

The construction of the nuclear power plant is linked with projects extending beyond the plant area, such as the con- struction of traffic connections or upgrade of the existing ones, the construction of the navigation channel, and the construction of power lines.

The location and construction of the navigation chan- nel in the sea area of the Hanhikivi headland is described in Section 3.6.2.

3.18.1 Traffic connections

Main road 8 (E8) runs through the village of Parhalahti at a distance of approximately 5.5 kilometers from the planned plant location (Figure 3-17). A smaller private road (Puustellintie) runs from the main road to the tip of the Hanhikivi headland. As Puustellintie is not suited for the nuclear power plant transportation operations, a new connecting road (Hanhikiventie) will be built from the main road to the plant area. The new road is indicated in the legally valid partial master plan and local detailed plan for the Hanhikivi nuclear power plant area. The length of the road from main road 8 to the boundary of the energy management block area indicated in the local detailed plan will be about four kilometers. The existing road (Puustellintie) will be upgraded, and it will function as a back-up access connection to the plant area.

The new connecting road will be two-lane asphalt- paved public road flanked by a pedestrian and bicycle way. Requirements relating to the construction and operation of the nuclear power plant will be taken into account in the dimensioning and design of the road. As required in the new regulatory guide on nuclear safety (YVL Guide D.4) issued by the Radiation and Nuclear Safety Authority (STUK), the elevation of the road will be dimensioned so that exiting the area will be possible also in times of excep- tional natural conditions. According to preliminary plans, the final elevation of the road will vary between +4.6 meters and +4.9 meters (N2000 elevation system).

Water supply and sewer pipe structures required for the power plant and the supporting areas, as well as the

related connections to the municipal network, will be constructed in conjunction with the building of the road. The entire road section will be equipped with lighting.

According to preliminary plans, the final section of the road line may be equipped with a bridge structure ena- bling the flow of water and animal movement across the road line at Hietakarinlahti. The structures and dimen- sioning of the road and the bridge structure will be speci- fied further during further design.

3.18.2 Power lines

The nuclear power plant will be connected to the Finnish national grid so that the grid connection enables, for its part, the safe and planned operation of the nuclear power plant, as well as the transmission of the electrical energy produced at the power plant to the grid in the planned manner under all grid conditions. Fennovoima will be responsible for the construction of the power plant connection lines, and the national grid operator Fingrid will have the responsibility for the grid reinforcements required in the main grid. The environmental impacts caused during the construction and use of the power lines will be assessed in a separate EIA pro- cedure, which is estimated to start in 2014.

According to the preliminary assessment, the connec- tion between the power plant and the grid will require the construction of a local connection with two 400 kV transmission lines and two 110 kV transmission lines. Fur- thermore, Fingrid estimates that securing the regional transmission capacity and the operational reliability of the power system would require two 400-kilovolt power line connections from the 400-kilovolt grid connection station between Hanhela and Lumijärvi.

The impacts caused to the nature types and plant and animal species constituting the basis of conservation for the Parhalahti-Syölätinlahti and Heinikarinlampi Natura 2000 area during the construction and use of the nuclear power plant and the associated power lines were assessed in the Natura assessment procedure for the Hanhikivi nuclear power plant carried out in 2009 (Pöyry Environ- ment Oy 2009a). According to the Natura assessment, the most significant risk was the collision of individual birds representing the species constituting the basis of conser- vation with the power lines. The assessment concluded in a recommendation to utilize the guyed H frame design in the construction of the power line towers as this enables the arrangement of conductor wires as low as possible,

Construction phase

(t/year) Operation phase (t/year)

Carbon monoxide (CO) 111 19

Nitrogen oxides (NO_x) 20 4

Small particles (PM) 0.5 0.1

Sulfur dioxide (SO2) 0.04 0.01

Carbon dioxide (CO₂) 6,730 1,219

Table 3-11. Air emissions from transpor- tation and commuter traffic to and from the nuclear power plant during weekdays, both during the construction phase and normal operation.

82 3 Technical project description

and at the same level. Figure 3-18 shows a cross-sectional image of the planned power line corridor implemented using guyed H frame towers.

Fingrid carried out a preliminary survey on the loca- tion of the power plant connection line routes in 2012. Figure 3-19 shows the power line routes and station loca- tions for the 400 kV and 110 kV local connections. These line routes have been taken into account in the prepara- tion of the regional land use plan guiding the planning of land use in the Northern Ostrobothnian region. All new power lines and station locations would be located within the municipality of Pyhäjoki. The total length of

the planned power line sections would be approximately 34 kilometers. The route section located in the Hanhikivi headland, the length of which is approximately 5.6 km, would begin at the nuclear power plant area and end east of main road 8, where the line connection would branch. The 110 kV line connection, indicated in red in Figure 3-19, would run from the branching point of the line route to the planned Valkeus substation. The length of the route section is approximately 13.8 kilometers. The 400 kV line connection would run to the planned Hanhela substation location. The length of the route section is approximately 14.6 kilometers.

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