Ghana - Thermal Power Project : environmental assessment (Vol. 2 of 7) : Takoradi Thermal Plant : summary

EnvironmentalNP Assessment/Analysis Reports____ ___ Report EOO5I Ghan'a .Thermal P6w:'er Poject. 1* .-.EA Category A Environmental Assessment' 2 of 4 August 1993 This report has been prepared by the Borrower or its Consultant  A Republic of Ghana Volta River Authority /n/l~~~~~ -/n /^X//s/s^ September 1993 Revised Jmnuary 7994 Acres International Umited Alli  Takoradi Thermal Plant Fnvironmental Assessment - Summary I. Introduction 1. This document Is a summary of the detailed environmental assessment report. entitled 'Takoradi Thermal Plant, Environmental Impact Assessment", prepared by Acres International Ltd (Acres) and issued as a final draft in August 1993. It also incorporates Information contained In two subsequent addendums to the EIA (September 1993 and January 1994). As such this summary highlights the main features of the propDsed development, the regulatory conditions, the existing natural and social setting, and the potential Impacts and measures proposed to mitigate and/or monitor those impacts. The Volta River Authority (VRA) proposes to build the Takoradi Thermal Plant on the southwest coast of Ghana. In the Western Region, east of the regional capital of Sekondi, near the village of Aboadze. The plant would be a nominal 300 MW combined-cycle, oil fired plant, consisting of two 100 MW combustion turbine generators (CTG), and one 100 MW steam turbine generator (STG), packaged as a 300 MW module. The site has the potential to accommodate a further 300 MW module, at a later date. The detailed environmental assessment report has been submitted to international lending agencies, Ghanaian government agencies, and the general public within the project area, for review and comment. Approval for the project is required from the Ghana Ministry of Mines and Energy, which receives input from the Ghana Environmental Protection Council (EPC) in terms of environmental issues. A detailed preconstruction mcnitoring programme, covering physical and biological characteristics of the local marine environment, terrestrial ecology of the site and transmission corridor, ambient site air quality and noise levels, is in various stages of implementation. This information will be used to verify initial assumptions of background conditions, and will be presented as an addendum to the EIA in its final issue. Due to the requirements of the various project financiers, the project has been divided into four separate funding packages, being combustion turbines, steam turbine and cooling water system, transmission facilities and project townsite. Revision 1, January 1994  2 11. Existing Setting and Proposed Development 2. Proiect Setting The project area is located approximately 15 km east of the cities of Sekondi-Takoradi, and is situated adjacent to a proposed urban planning zone. The site itself is approximately 2 kM2. and Is located on the ocean shoreline, within 0.5 km of the fishing village of Aboadze. A 5-km long, gravel road bisects the project site, and connects Aboadze and the adjacent community of Aboesi (2+ km to the northeast) to the main coastal highway. The site location provides close proximity to the national grid, as well as a centre of demand. The location of the site is shown in Figure * ~~~1. 3. Proposed Plant The Initial plant would consist of a 300 MW combined cycle module. It is expected that the plant would expand to 600 MW at some point in the future, hence the cooling water circuit has been sized to meet the requirements of a second STG unit, and the site is of sufficient size to accommodate the second module. The plant will bum principally light crude oil, with the provision to utilize distillate oil as needed and natural gas when available. A tank farm would be developed on site to retain a minimum 60 day operational supply, and an oil treatmenVcleaning facility will be provided to maintain consistent oil supply characteristics for the combustion turbine burners. Cooling water will be drawn from the sea through a 3.0 m conduit at a rate of 5.7 m3/sec for one STG operaton. Both the intake and discharge will be located offshore beyond the 6-m contour. The final location of these structures will be determined pending the outcome of marine fisheries and geotechnical investigations. 4. Land Use The site area south of the access road consists of seasonally inundated lowland areas and 35-40 hectares of subsistence level agricultural farm plots on higher ground. No dwellings exist on or immediately adjacent to the project site. A band of coconut palms, approximately 100 m in width, are present along most of the beach ridge fronting the site, with the exception of a small central area, previously subjected to sand excavation. The proposed plant would be situated on this portion of the site. The site area north of the access road consists of seasonally inundated lowlands to the west, and higher. occasionally steep-sided hills, to the east Isolated farm plots occur on higher ground, and a strip of coconut palms fringe the access road. Much of the proposed transmission route is also planted to coconut palms, with the exception of several low lying areas, and some isolated farm plots. 5. Air Quality Air quality monitoring was initiated at the site in February, 1993. and mwill continue with specific studies throughout the preconstruction, construction and operational phases.  3 The February study was designed specifically to measure suspended particulates. This monitoring indicated a moderate concentration (average 94 ig/rmn). with salt spray and wood smoke being major contributors to suspended particulate concentrations at the site. Ambient air quality monitoring was undertaken at three locations upward and downwind of the proposed plant site (beach ridge, site access road and Aboadze-Aboesi road) during August 1993. Ambient one-hour SO2 concentrations ranged from non-detectable levels to 1 60Dpg/m3 at individual sites, while average concentrations at the three locations, were 23 pg/rm3 near the southwest corner of the site. 34.6 g/rM3 near the northeast comer of the site, and 3.5 pg/M3 at the third location between Aboadze and Aboesi. Ambient NOx concentrations were also measured in the vicinity of the site during August and September 1993. NOx was not detectable during sampling device exposure times up to 7 days at any of three locations (SW, SE and NE of proposed site) sampled, and was less than 7 ag/rM3 at each location during exposure periods of 30 days or more. Thus, particulate concentrations at site are moderately high, primarily due to the coastal location and the extensive use of wood for fuel and fish smoking, while background levels of NOx and SO2 are both low, indicating basically an unpolluted environment. 6. Noise Background noise levels in the project area were monitored at three locations near the c;ite in mid-August. 1993. Over a 24 hour sampling period, average background levels ranged from 42.3 to 49.5 dBA near the school on the western outskirts of Aboadze, from 42.3 to 54.9 dBA on the beach near the settlement at the southwest corner of the site, and from 43.3 to 56.1 dBA near the cemetery at the northeast corner of the site. Design specifications for the plant will be such that noise levels at 1 m from operating equipment will not exceed 85 dBA, and noise levels at the plant fence will not exceed 55 dBA. 7. Water Resources Upon completion, the plant will have a requirement for approximately 1500 m3/d (400,000 US g/d) of fresh water, which includes water for NO, control, boiler feedwater makeup, fire and service water, and potable water for the plant and townsite. The Ghana Water and Sewerage Corporation has indicated that this amount will be available from the municipal water supply (150 mm pipeline) that feeds Aboadze and Aboesi by the year 2000, and that 950 m3/d (250,000 USG gld) will be available by 1995. However this supply is occasionally erratic, particularly during dry periods. Hence, a desalination plant capable of supplying 300,000 g/d (1150 m3/d) will be installed as part of the STG contract package, in order to provide water for NOx control. In addition, the 300 MW plant will draw 5.7 m3/sec of water from the sea for condenser cooling. Water will be drawn and discharged through intake and discharge structures  4 located on the seabed offshore of the plant, through a 3.0 m tunnel. Preliminary Indications are that the intake will be situated near the 10 m contour, while the discharge will be offshore of the 6 m contour. The 300 MW Installation would discharge cooling water at 90C above ambient, while the potential 600 MW plant would discharge cooling water at 120C above ambient. The final location of both structures will be determined following completion of, and utilizing input from, the marine fishery and geotechnical investigations. 8. Oil Oil contamination of beaches along the coast of Ghana is not an infrequent occurrence. Much of this is thought to result from offshore tanker traffic and discharges, although other sources such as refineries, municipal and Industrial discharges, offshore oil exploration and disposal of used crankcase oll, are also contributors to the problem. In the coastal zone, oil occurs as either liquid or tar balls, and has been reported locally at concentrations up to 24 g/m2 on the beaches. At baseload operation, the 300 MW plant will require approximately 1600 tonnes of oil per day. This oil will be delivered to a tank farm on site via a pipeline on the seabed from an offshore single point mooring (SPM) oil transfer buoy. The tank farm will have storage capacity for 120,000 m3, which is sufficient for a 60 day operating supply. The SPM is scheduled to be located in 20 -m of water, thus providing sufficient water depth to accommodate delivery tankers up to 80,000 dwt. 9. Socioeconomic Setting The local communifies (Aboadze, Aboesi and Shama) are primarily fishing villages which rely heavily on the offshore Sardinella fishery for income. Most fish are smoked in the villages and sold outside the local area. No other significant industry or source of income is reported for these villages. Other species found in the nearshore zone comprise the majority of the fish used for home consumption, although some Sardinella is consumed locally. Subsistence level agricultural activity is practised within the plant site area on the higher ground (some 35- 40 ha). The land tenure system is such that the land being farmed, is cropped by subsistence farmers who do not own the land. Aboadze has two primary schools and shares a junior secondary school with Aboesi. Aboadze Is supplied with electricity, and has a police station, but no medical facilities. There are no solid or domestic waste disposal facilities near the site, and as such both domestic refuse and human excreta are discharged directly to the sea. 10. Historical, Cultural and Aesthetic Resources No historical resources have been identified on the site. The closest structure of historical significance is Fort San Sebastian at Shama (a distance of 5 km). The nearby communities are primarily fishing villages, which are comprised of peoples from a number of ethnic groups, who originally migrated to the area to fish. Each retain portions of their own culture and often retum to native towns for festivals and celebrations. Three minor shrines are present on site, which will  5 need to be propitiated prior to site development. Aesthetically, the site beach area Is very pleasing and the shoreline area from Sekondi to Shama has been identified as one having future tourist potential. A tourist resort Is In the Initial stages of development approximately 3 km west of the proposed site. 11. Waste Management During the construction process solid, liquid and domestic waste AIll be created. A solid waste disposal site will be created near the project site. The location of the site will be subject to approval by the local authority, and will be engineered so as to prevent contamination of groundwater. Waste materials will be reused and/or recycled to the greatest extent possible. A sewage lagoon will be installed to handle domestic wastes originating from the plant, contractor's construction camp and townsite. Numerous waste products will be created during plant operation. Uquid effluents originating from the various producers on site (ie., sewage lagoon, oily waste treatment and oilVwater separator) will be treated so as to meet applicable criteria for steam generation plants. Solid wastes will be either disposed of at the site created during construction, or transferred to operational sites near Sekondi-Takoradi. Wastes from the oil treatment/cleaning facility will be stored and burned in an incinerator specifically designed for that purpose. Other oil sludges or similar byproducts generated within the plant will also be disposed of at this facility. 12. Worker and Public Health and SafetY Construction activities and the increase in traffic on the project access road could increase the risk of injury to workers and the public. Speed limits will be posted and enforced for construction vehicles, and local communities will be informed of the construction schedule. Fly rock will be controlled during blasting operations, and appropriate warning systems will be developed to advise of blasting actMty. It is not anticipated that nearby communities would be impacted by blasting activities. 13. Public/Community Consultation Discussions have been conducted with landowners and community elders to determine the overall availability of the land for the proposed project. The final draft of the environmental report has been made avaiDable for public review, and public meetings have been held in Accra and Takoradi to assess community reaction to the project. Discussions with community representatives are ongoing towards development of a Community Impact Agreement. which will define compensation and mitigative measures which will be provided to the village of Aboadze by VRA.  6 N11. Environmental Impacts 14. Land Use In the order of 35 - 40 ha of land currently used for subsistence level agricultural activity at the proposed plant site will be lost at implementation of the project, however the coconut plantings along the beach strip will be preserved. No other commercial plantings of tree crops exist on this portion of the site. In addition approximately 70 ha of land north of the access road wll be required for the construction and operational staff townsite. Along the transmission route, some clearing of coconut plantation will be required for tower placement, and to avoid contact with transmission lines. A number of small farm plots may also be disrupted along the transmission route. Detailed studies to assess land use and appropriate compensation levels are ongoing at the site and along the transmission route. 15. Air Quality No adverse effects on air quality are predicted during the construction phase, as appropriate mitigative measures have been proposed to control emissions, especially particulates. No adverse impacts to air quality due to plant operation are predicted as NOx and SO2 emissions will both be controlled as described in Section IV. Particulates and CO emission rates are well below recommended limits. Emissions from the waste oil incinerator will also meet the air quality criteria specified for the plant. 16. Water Resources Local drainage patterns will be disrupted and modified during site development. This could result in some additional loading of sediments to local watercourses. Settling ponds/basins will be installed and utilized prior to stabilization and/or revegetation of site ground surfaces to minimize this potential impacL Offshore construction activities associated with the installation of the SPM, oil pipeline, and cooling water circuit portals will result in local increases in turbidity, and some disturbance to the marine community. These activities will however be shortlived, and as such wil have minimal impacts. Although no specific monitoring program is proposed for these activities, contractors will be sporadically checked to ensure that 'best management practices' are being utilized. No adverse impact is anticipated from the withdrawal of 950 m3/d (250.000 USG/d) from the Aboadze/Aboesi municipal water supply, as it is currenty being upgraded to meet future needs. In addition, a storage reservoir of 3785 m3 (1,000,000 US gallon) capacity will be established on site. In the event that the GWSC supply is unavailable, water will still be available for plant operations from the desalination plant. Discharge of liquid effluents to the Anankwari River feeder stream will meet specified criteria, but may have limited impacts, particularly during periods of low stream flow. This discharge will be diverted to the cooling water discharge when it becomes operational, which will eliminate potential impacts within the Anankwari River.  7 The plant will be designed for a cooling water discharge temperature of 9