Announcement
Fri, 17/06/2016, 08:50 GMT+7
Executive summary environmental impact assessment for Song Hau 1 thermal power plant, Vietnam
This Environmental Impact Assessment (EIA) was prepared for Song Hau 1 thermal power plant which will be built at the site of an existing power station in Hau Giang province and it was approved by the Minstry of Natural Resources and Environment in Decision No.1455/2007/QĐ- BTNMT dated July 25th 2011.

Recent years, resulting from the economic renovation, Vietnamese economy has grown strongly. Living standard has been increased. Vietnamese economy is on its way to integrate into the economy of the region and of the world. Electricity demand has also increased along with this process.

In order to meet the power demand, Vietnam Electricity (EVN) has to hasten construction progress of power plants and grids. Further EVN has also had a plan to reasonably balance power capacity at each region, to ensure the reliability of power supply. The development of thermal power plants near the load center has high priority to reduce the transmission of power through a long distance. Thermal power plants should be developed, in which the coal- fired thermal power plants should have high priority to increase the initiative and safety in fuel supply.

Song Hau 1 Thermal power plant project is located in Song Hau - Hau Giang power complex which will be built in Hau Giang province.

The Song Hau - Hau Giang power complex is one of the coal thermal complexes in the Southern region which planned according to the Master Plan VI. It has been approved by the Government in Decision No.110/2007/QD- TTg dated July 18th 2007 to ensure power supply for the development of national socio-economy during 2006 - 2025.

Song Hau power complex is located on riverside of the Hau river belonging to Phu Huu A Industrial Group (Mai Dam town, Chau Thanh district, Hau Giang province). Location planning of Song Hau power complex was approved in Decision No.6722/QD-BCT dated Dec. 23rd 2008 by Ministry of Industry and Trade. Overall planning of Song Hau power complex (version No.3) are approved by the Ministry of Industry and Trade in Decision No.1155/QD-BCT dated March 8th 2010.

Land clearance and investment of infrastructures (including access roads, management building, embankment, equipment and material ports, power and water for construction, etc.) of Song Hau thermal power complex belong to the “Infrastructure of Song Hau thermal power complex” project. Environmental Impact Assessment report of the “Infrastructure of Song Hau thermal power complex” project was approved by Hau Giang Provincial People’s Committee in Decision No.190/QD-UBND dated Feb.9th 2011.

According to Decree No.21/2008/ND-CP dated Feb.28th 2008 and Decree No.80/2006/ND-CP dated Aug.9th 2006 of Government on guidance details of articles of Law of environmental protection, the Song Hau TPP has a capacity of 1,200MW, it has to set up EIA report and submit to Ministry of Natural Resources and Environment for approval.

1.        Description of the operation

The Song Hau 1 TPP with an area of 115.2ha is constructed after finishing period 1 of the “Infrastructure of Song Hau thermal power complex” project (cleared the ground and finished building infrastructure of the Song Hau 1 TPP). Scope of the Song Hau 1 TPP is as follows:

-    The main items of the Song Hau 1 TPP: 2x600MW turbine units with conventional technology, once through pulverized coal fired boiler with reheat, super steam pressure, advanced combustion technology    (low    NOx burner), equipments flue gas treatment will be installed to meet environmental requirements.

-   Auxiliary systems: storage and supply systems of coal, oil, limestone, gypsum, ash discharge system, ash disposal area, cooling water system from Hau river, fresh water supply system, waste water treatment system...

To meet environmental regulations, the plant will install the NOx removal system, dust removal system and SO2removal system.

SOx removal (Flue Gas Desulfurization - FGD):

The plant will apply the chemical absorbing process to treat SOx with limestones agent. Flue Gas Desulfurization by Wet Limestone Scrubbers is selected because it is in accordance with coal type having high content of sulphur and have a high efficiency.

This method is very popular in the world and has been proved through manufacture and operation. In this method, the flue gas from boiler carrying SOx will be directed to the wet absorption tower.

The operation process of FGD is as following: the limestone after transport to the plant being stored in the storehouse with the roofs. Here, it is grinded smoothly and mixed with the highly pH water from cinder and ejected into the absorbing tower.

The suspension of the limestone is ejected into the tower from the top to the bottom, then the air emission goes up. There are reactions of the chemicals and the sulfur composition in the tower to reduce the concentration of SOx.

The mixed solution of the humid gypsum is pumped to the vacuum filtering model to dewater. Right here, the gypsum is dewatered to the humidity of 15% and then keep in the gypsum storehouse. This gypsum product can be packed and supplied for construction materials.

Dust removal (Electrostatic Precipitator - ESP):

The flue gas laden with fly ash is sent through discharge electrodes which give the particles a negative charge. The particles are then routed past positive plates (grounded collection electrodes), which attract the now negative ash particles. The particles stick to the collection plates until they are collected. Removal is accomplished by a mechanical rapper system knocking the ash particulate matter off the collecting plates and dropping it into a hopper at the bottom of the precipitator. Then the ash particulate will be discharged to the ash and slag discharge system or the ash silo.

2.             Description of the existing environment

The topography of the project area is quite plain, little rivers, mostly ricefield. Population is mainly concentrated along the dykes, houses are not permanent and sparse. The average height is around 0.6 to 1.5 m and some places are lower. This area is located in inner belt of the tropical Northern Hemisphere, near the equator, has a tropical monsoon climate divided into two distinct seasons. There is Southwest wind in rainy season from May to November, Southeast wind in dry season from December 12 to April every year.

Water level on the Hau River at Can Tho - Song Hau area is strongly influenced by the tidal regime. There are two tidal peaks and two tidal foot but not equal in one day and night time (for 24 hours) - uneven Semi diurnal regime. On the other hand, water level regime in this area shows the runoff regime of a river: flood and dry seasons. According to the document of the hydrologic Can Tho Station, flood season often begins from August through the following January, dry season from February to July. Minimum average water level often occurs in May or June, Maximum water level in October or November. According to result of the survey in Aug. 2009 in the project area, there are about 154 species of plants of 61 families. There are no precious plants species in the Red Book of Vietnam and the UICN.

Land resource

Total amount of natural land of Hau Giang province is about 160,772 ha. There are three main types of land such as alluvial soil (occupied approximately 42% total natural area), alkaline soil (41% total amount), and and other soil (17% total natural area).

 Water resource

Hau Giang province has plentiful water resource included surface water and underground water. Surface water is supplied by Mekong Delta systems. This is ensured sufficiently water for irrigation, domestic animal and living of the locals. Associated with these advantages, Hau Gianghas very abundant aquatic resources such as fisheries with plenty seafood, farming aquaculture and catching, etc. has bought great economic profit for the locals.

Biological resource

Currently, in Hau Giang provinceTrên địa bàn tỉnh Hậu Giang đã hình thành Lung Ngoe Hoang ecological conservation and Scientific and Research conservation at Hoa An commune (Phung Hiep district). These consevations are step by step to restore and reserve natural flora and fauna systems in flooded forests and flat plain freshwater.

Mineral resource

Hau Giang is a neoplain which has less mineral resources. There are clay for bricks, plastic clay, a few of peat coal (mostly in Long My district) and bank sand.

3.                Significant environmental impacts

3.1.          Impacts during construction

3.1.1.   Impacted objects related to waste

3.1.1.1.       Impact on air environment

In the construction phase, ambient air quality will be impacted by transportation means, construction equipments, earthworking, and transportation of construction material. Pollutants are mainly dust, exhaust fume with CO, SO2, and NOx.

·                                Dust

During construction phase, dust can be caused by: (i) earthworking activities; (ii) transportation and unloading of construction material and equipments.

in which earthworking activities are main source caused dust.

-                 Dust from earthworking activities.

Earthworking activities is main source generating dust affect to the quality of ambient air quality.

-                 Dust from transportation and unloading of construction material and equipments:

Transportation and unloading of construction material and equipments (cement, soil, sand and stone, etc, ...), soil and sand from dredging of intake, discharge canal, etc,...will cause dust. Moreover, in construction material gathering site, unloading will also cause dust impacts on construction workers and ambient air environment.

However, construction material and equipment will be carried mainly by waterborne, so amount of dust and its impacts on surroundings are inconsiderable, interruptive and only occur during transportation time.

·   Exhausted gas

Activities of execution means cause many kinds of exhausted gases as:

-    Smoke from solder with dust, CO, SO2,NOx, etc.

-    Exhaust fume of transportation and execution means with dust, CO, hydrocarbon, SO2, NOx, etc. These means are: excavators, tons self­unloading trucks, etc.

-    The project could use stand-by generator which is source of air pollution, such as: SO2)NOx, CO, dust, VOC, etc.

3.1.1.2.       Impact of noise and vibration vibration

During the construction phase, noise can be caused by:

-   Construction of coal port consisting of pile foundation consolidation may cause noise at high level and vibration (about 110dBA).

-    Machines, equipment for construction (bulldozers, concrete mixers, many kind of air-hammers, excavators, air compressors, etc.);

-    Boat/carriers, mechanical transporters of construction materials and equipments.

3.1.1.3.       Impact on water environment

During the construction phase, waste water source is mainly domestic waste water.

There is no any drainage system in the project area. A domestic waste water treatment system will be also built early in the construction phase in order to limit impacts of untreated domestic waste water on soil, underground water, surface water, public health in the project area indirectly.

3.1.1.4.       Impact of solid waste

Solid waste consists of construction waste and daily domestic waste of workers in the construction phase.

-    Construction solid waste consists of refuse materials such as steel scrap, brick, stone, cement, etc. Amount of these wastes are estimated about 500kg/day. These waste will be reused for leveling (for crushed brick, stone, rubble, etc.) or for sell (steel, etc.), so its impact is inconsiderable.

-    Domestic solid waste

Concentration of construction workers in large numbers in a long time will generate domestic solid wastes.

The project will contract witha company capable of waste treatment, periodical this company will collect and transport domestic solid wastes to an appropriate sanitation treatment place, so the impact is considered insignificant.

3.1.1.5.       Impact of hazardous waste

Hazadous waste in the construction phase is mainly eliminated lubricant from machines, equipments and means for the construction, vehicles, oily clouts which may cause fire-detonation and pollution of water and soil.

The project will contract with a specialized company in transportation and treatment of hazardous waste. Monthly, this specialized company will transport and treat all hazardous wastes generated at construction sites.

Collection, classification, storage and treatment of hazardous wastes will comply with the regulations on management of hazardous wastes. So, its impact on the environment and health is small and can be controlled.

3.1.2.   Impacted objects no related to waste

3.1.2.1.   Impacts on ecosystem

In construction phase, exhaust gas and dust caused by construction activities will impact on photosynthesis process of vegetables in surrounding area. However, the left and right sides of project area are bordered by river and there are many canals. Thus, this impact is considered low and minimizable.

Runoff goes over earthworking area will carry waste, grease which are pollution source of surface water and could impact on ecosystem of the project area.

3.1.2.2.   Impacts on the local landscape

The landscape shall be impacted by construction activities. Also, excavating and discharging construction solid waste, soil and rock without clearance shall lead to a disorderly landscape.

The proposed project area is not located closely to protected    or tourist areas.

Related to affected temporary areas in construction phase, when contruction activities are done the landscape shall be recovered as same as the original existing does. Thus, this impact can be avoided but minimized.

3.1.2.3.   Impacts on socio-economic situation

Construction activities could impact on the local socio-economic status due to concentration of a large numer of workers. Concentration of construction workers could cause social issues. Construction activities will also mobilize a large number of local labours, contribute to employment creation for partial local leisured labour which boost development of business activities and services in this area.

However, apart from positive impacts mentioned above, concentration of construction workers could cause social issues as: uncontrolled emigration from other places, increasing problems of public order and social evils. In addition, conflicts between construction workers and local inhabitants could be occurred. This is a unavoidable kind of contradiction but could be minimized.

Concentration of a large number of construction workers could also pollute water resource, epidemic of disease, and pressurize into local system health if management and treatment of solid waste and wastewater was not implemented sufficiently.

Implementing project contributes jobs and improve living standard of the local, and give chances for some families by developing some services and entertainment.

3.1.2.4.   Impacts on protection area, cultural and historical monuments

Concerning results of field survey, public consultation and confirming information from the local authority, it is evident that the proposed project area is not located in protected area, cultural and historical monuments. Thus, this impact is non-existence.

3.2.          Impacts during operations

3.2.1.   Impacted objects related to waste

3.2.1.1.   Exhausted gas from stacks

Song Hau 1 TPP is proposed to use coal imported from Indonesia or Ustralia as main fuel.

Fuel combustion process will cause air pollutants such as SO2, NOxand dust. Concentration of these pollutants depends on combustion technology and conditions, kind and composition of fuel. Thus, the report will consider main pollutants in the exhausted gas such as dust, NO2and SO2.

To calculate emission rate and concentration of pollutants in exhausted gas of the plant, the project uses Steam Pro software. This software is designed based on the combustion characteristics of the boiler.

The program will calculate heat balance and efficiency of the plant. Besides,based on the combustion of the fuel, the program will calculate the concentration of exhausted gas into the atmosphere. In addition, the program can find the parameters of main equipments and devices.

Table 1: Parameters used for calculation of emission rate

Parameter

Song Hau l TPP

Capacity (MW)

2x600

Boiler type

pulverized-coal-fired boiler

Steam parameters:

 

Pressure super critical

250bar

Temperature high pressure / return baking

540-5 60°C

gas

Annual consumption coal (tons/yr)

3,660,585

Average annual operation time (hrs/yr)

6,500

Total volume of emission gas (kg/h)

2x2,285,200

Gas temperature in the stack mouth (°C)

82.05

Velocity of emission gas (m/s)

21

Stack diameter (m)

2 x 6.2*

% Sulfur in coal (%) (adb)

0.86

Coal ash percentage (%) (adb)

12

Volatile (%) (adb)

42

 

Notes *: 02 stack of the plant will be located side by side with an inner diameter of 6.2 m for each.

Calculation results are as follows:

Table 2:  Emission rate and concentration of pollutants in exhausted gas of the Song Hau 1 TPP

Calculated

parameter

Emission rate .

(g/s)

Concentration

(mg/Nm3)

QCVN 22:2009/BTNMT (C­max=Ctc*Kp*Kv) with Kv=1.2; Kp=0.85 (mg/Nm3)

Dust

11,725.3

11,639

204

SO2

1,994.72

1,980

510

NOx

<452.56

< 450*

663

 
 

 

Notes:* Low NOxtechnology combined with air staging method will be used in order to ensure that NOxconcentration is less than 450 mg/Nm3which is technical constraint condition in bidding document and contract of equipment suppliers.

3.2.1.2.   Dust from coal port and coal transportation

Coal transportation will use specialized ship/barge with 10,000DWT. Thus, this impact seems to be none.

In the port area, activities of coal transportation will cause dust. However, the power plant will use closed-type conveyor system for transportation, so it will minimize amount of dust.

In the port area, activities causing air pollution is very light, only a small amount of dust and emission gas is generated from transportation and unloading of equipment and machines, All the machines and equipments in the port area use diesel oil for their fuel source. Thus, all the kinds of the pollutants caused to the air due to the operation of these kinds of means include: CO, NOx, SOx, hydrocarbon, dust, lead dust, and aldehyde. Concentration of these pollutants depends on the capacity and operational system of all the types of means.

3.2.1.3.   Dust from coal storage area

Coal storage of the Song Hau 1 TPP is located in the North East of the plant. Coal storing and loading process will cause dust and impact on the ambient air quality.

However, coal loading is not continuous, coal storage isn’t always in full load status and mitigation measures will be applied (barrier, sensor, dust immunity .. .), so this impact is at low level and minimize.

3.2.1.4.   Dust from ash removal

The power plant use coal as main fuel. With the pulverized coal fired boiler technology, ash discharged from the boiler is mainly in two forms: bottom ash, and fly ash.

Bottom ash: occupies 15%, collected by hydraulic bottom ash system technology, or of high concentration slurry disposal technology.

a.     Fly ash: occupies 85%, fly ash accumulates at the hoppers of the economizer, air heater and ESP, economizer, reheaters. Fly ash is collected to ash silos with enough capacity for 48h full loads operation. If required to consume, ash will be supplied directly from silos.

b.     Ash discharge

By-product ash of bituminous coal is often has high quality and it can be used as additive for cement. Based on that, the ash handling system is designed as follows:

-    Ash is used as additive materials for cement, it will be supplied directly under dry form from the silos through an ash pipe of about 300m and then transported by trucks and 1,000 - 3,000 DWT barges,

-    In case of accidents or congestion due to unconsumed, ash will be transported to the ash disposal pond by mixed with water to form an ash slurry. Then it will be pumped to the ash disposal pond.

3.2.1.4.1.      Dust from the ash disposal pond

The ash disposal area is in the triangle land with acreage about 33ha. Dike body of ash disposal area is constructed on weak ground base with average length of 16m, so quantity of dike body has to be considered to surrounding constructions to have suitable solutions and safety distance to surrounding constructions.

The ash is transported to the ash disposal pond by mixed with water to form an ash slurry. Hence, the ash disposal pond always has water on the surface layer, so the amount of dust dispersed into the surrounding area is low.

In the ash disposal pond, dust can be generated from ash exploitation activities by local people. This impact is very small because the ash disposal pond is in the plant fences, the project will strengthen the management measures and prohibit exploitation activities of local people.

3.2.1.4.2.      Dust from limestone storage area

Limestone dust may be generated from limestone storage area, affects to air quality in project area. However, limestone storing area is covered and the power plant will apply mitigation mesures, so this impact is not at high level.

3.2.1.4.3.      Emission gases from transportation vehicles in the power plant

Traffic activities in this area are mainly transportation of limestone, workers, maintainance experts, and activities of some lifting-trucks.

There are approximately 16 10-tons-trucks running 15 km on roads daily. The amount of pollutants due to limestone transportation is 10.5g of dust, 3g of S02, 30g of N02,256g of CO, 36g of VOC.

There are approximately 15 30-seats-buses picking-up workers and running 10 km on roads daily. The amount of pollutants due to picking-up workers is 16.8g of dust, 4.66g of S02, 60g of N02, 357g of CO and 45g of VOC.

Based onthe above data, it could be concluded that impact of vehicles in the plant area to air quality is insignificant because of low traffic density and small loading of vehicles. However, the power plant will consider this impact to keep air quality in the area.

3.2.1.4.4.      VOC leakage from fuel tanks

DO is used for boiler starting-up and firing at load lower than 30%.

The leakage level of oil in oil tank area depends on tight-fitting of the conveying system and tanks, denpends on the intake structures of the tanks, as well as temperature and humidity of surrounding air,.... The pollutants that can affect to the health of inhabitants in this case are derivative hydrocarbon at certain concentration.

3.2.1.4.5.      Impact of noise and vibration

In the port area, noise and vibration generate from follow activities:

-    The operations of the machines of the ships, barge, bucket elevator unloader,... mooring and leaving the ports;

-    The operations of the means of stevedoreing and transportation at the wharf of coal, limestone, oil such as the crane truck, forklift truck, trailer, the conveying belts....

-    The operation of the DO oil pumping system;

-    The activities of loading and unloading of the machines and equipments and the activity of gas and oil supplying station.

In there, main sources of noise and vibration are activities of conveyors, stevedoreing equipments, and pumping fuel from barge to storage. According survey results at some materials wharfs, noise level can be up to 70 - 80dBA.

In the plant area, noise can be generatedfrom some equipments such as turbine, blower, air compressor, pumping engine, boiler...

3.2.1.4.6.      Impact on water environment

The Song Hau 1 TPP will take water from the Hau River. The Song Hau 1 TPP in the operation phase will discharge types of waste water such as:

-    Overflow rainwater.

-    Domestic waste water.

-    Production waste water.

Regular:

-    Waste water from ash removal system

-    Waste water from coal storage area and cleaning coal conveyors

-    Oil-contained waste water

-    Waste water from fresh water treatment system

-    Waste water from exhaust gas treatment system

-    Boiler blowdown

-    Cooling waste water

Irrugular:

-    Waste water from chemical cleaning boiler

-    Waste water from washing Air Heater

-    Waste water from washing boiler

Discharged cooling water of the Song Hau 1 TPP has effect on temperature of river water in surrounding of water outlet, range of influence has a radius of 1,870m.

-    In case the Song Hau 1 TPP in operation only, temperature of river water will be increased not rather than 1.01°C in a radius of 150m, and not less than 0.42°C in a radius of 1,730m.

-    In case the Song Hau 1, Song Hau 2 and Song Hau 3 TPPs in operation together, temperature of river water will be increased not rather than 3.22°C in a radius of 150m, and not less than 1.3°C in a radius of 1,870m.

-   Impact of increased water temperature on fish.

-   For marine aquatic species, variable temperature species, animal heat differ in a range of 0.5-1°C in comparison with the surrounding water temperature. Thus, water temperature has vital influence and directness to mass exchange process of fish. In nature, fish adapt easily to seasonal changes. For example, in temparate countries, temperature amplitude between winter and summer season ranges from 0°C to 30°C. However, fish may have thermal shock when they are put into new environment in which its temperature changes suddenly warmer or cooler than that of the previous environment in a range of 8-12°C. In this case, fish may die or has paralysed symptom of respiration activity and myocardium. For young fish, this reaction will occur as soon as temperature changes suddenly from 1.5 to 3°C.

-   For aquatic organism in Hau river in general and in project area in particular, there is yet any document mention their lethal threshold. Based on the result of the above caltulating model, most circle of influence of cooling water has a temperature difference not rather than 1.30C in comparison with inlet water. Thus, this has insignificant impact on aquatic organism.

Impact of increased temperature on bottom organism

Based on the above caltulating model, the average temperature of Hau river is 30°C. If the Song Hau 1 TPP discharges cooling water then temperature of Hau river causes is increased not rather than 1.01°C in a radius of 150m, and not rather than 0.42°C in a radius of 1,730m. In case all three plant of Song Hau 1 TPP in progress, then level of increased temperature is not rather than 3.22°C in a radius of 150m, and not rather than 1.3°C in a radius of 1,870m. At that situation, the highest temperature is not rather than 33.22°C in a radius of 150m. This has yet large influence to the local bottom organism system. Regarding laws of nature and experiments in Ecological Centre (National Centre for Science and Technology) for some species of aquatic organisms such as Metapenaeus ensis, Macrobrachium rosenbergii, Perna viridis, etc. the highest lethal temperature causes totally 100% death at a range 40°C - 42°C. In fact, temperature amplitude for generation of tropical fauna species in nature from 20°C to 34°C, and optimum one is from 25°C-28°C. Therefore, firstly it should notice to development of sticking fauna which can harm hydroconstruction in project area such as Teredo navalis, mussels, etc. Their first mass exchanges are decreased at a temperature of 35°C. From 37°C to higher, intensity of tropical fauna species are decreased heavily and they are died at a range 40°C-42°C.

Impact of increased temperature on micro-organism

Increased temperature also affects to micro-organism, at 16 - 19°C diversity of micro-organisms is highest. Diversity reduced by the increase of temperature but increase amount of individuals.

Common remark: the above citation is for reference only because up to now there is not any research for waste heat impacts assess of cooling water of thermal power plant in Vietnam. However, when the Song Hau 1 TPP in operation, it may occur a mix which change ecosytem in project area. Thus, impacts of increased temperature shall be periodically monitoring.

3.2.1.5.       Impact on soil waste

Activities of the power plant can generate production waste and domestic waste such as:

-   Domestic solid waste: generated by activities of operation workers (about 450 persons).

-   Residue amount is discharged by burning coal.

-   Gypsum amount generates after exhaust gas treatment: a maximum of 522tons/day, approximately 141,000tons/year (type S 0.86%).

-    Solid waste from washing boiler.0.5 ton/time (periodically once/year). This contents metal, salt, low pH, etc.

-    Solid waste from waste water treatment system: 0.2ton/day. This is formed by dead body of microorganism, solid waste matter, etc. Waste waster treatment system separates hanging solid waste matter and solid wastes before it is treated biology or chemical (neutralizing).

All of above solid wastes will be collected and transferred to suitable treatment place by contracts with specific companies. Besides, the project will apply not only mitigation measures to minimize amount of solid waste, but also waste classification at sources for reprocessing, reusing and treatment.

3.2.1.6.       Impact of hazardous waste

Hazardous waste of the plant is oil sludge.

There are hazardous wastes with small amount such as oil-tubs or being infected by oil things, lubricating oil generate by maintaining machinery and equipment, oil from transformer take form in maintaining processing (this oil does not contain PCB - Polychlorinated Biphenyls) which cause of fire - detonation and water, soil pollutions.

The plant will sign a contract with specific company to collected, classify, storing and transport the whole generated hazardous waste following assign of hazardous waste management regulation. So, its impact on environment and health, specially be subject to fire-detonation is minor and under control.

3.2.2.   Impacted objects no related to waste

3.2.2.1.       Waste heat (heat pollution)

Main waste heat creating source is from gas oven areas. But nowadays all gas ovens are covered by insulating skin to sure skin-temperature lower than 50°C. Oven-smoke temperature is about 80°C dispersing at height from 140m to 200m; then, it is dispersed well.

Subject is affected by factory heat pollutions is operating worker. While they regularly monitoring and maintaining as stipulated will limit these impacts to minimum.

Beside, fuel tanks are implicit environmental threat during construction phase. Oil leakage and construction activities as: autogenous welding and electrical shock are threats which could cause fire hazard in construction site. Main reason causes risk at fuel tanks are corrosion of tank wall or defective wall in process. In addition, it is incorrect operation of labors. Thus, safety measures applied storages (specially fuel tanks) will be interested in and be controlled seriously.

4.      The Proposed mitigation measures

4.1.  Measures during construction

 Main buildings and facilities of the Song Hau 1 TPP will be on the existing power plant site. All preliminary works relating to the construction, site preparation and organisation, except the off-site area for parking and materials storage, will be located inside the existing site.

 Preparation, classification, packaging and transportation of waste generated during dismantling of the storage tanks will be carrieance with the statutory provisions concerning process waste. The collection, storage and transportation will comply with regulations on hazardous waste management in the Circular No.l2/2006/TT-BTNMT of Ministry of Resources and Environment.

 The existing water supply system will be reconstructed to provide raw water for the Song Hau 1 TPP. All works will be executed to preserve the original land use.

4.2.  Measures during operations

Air protection

To meet National technical regulations QCVN 22:2009/BTNMT and QCVN 05:2009/BTNMT and preventive exhaust emissions for factories in Song Hau power complex, the Song Hau 1 TPP will install a exhausted gas treatment system with devices and treatment efficiencies as follows:

-    In the initial phase (only Song Hau 1 TPP in the Song Hau power complex), the Song Hau 1 TPP installs only the dust removal system (99%) and the SO2 removal system (80%). However, ventilation fan system, power system, control system are designed and selected for installing the NOx removal system in the next phases.

-    Calculated reasults show that after installing the above treatment system, exhausted gas of the Song Hau 1 TPP meets QCVN 22:2009/BTNMT at the stack mouth and QCVN 05:2009/BTNMT on ambient air quality.

Water protection

 To minimize impact of waste water, the project will implement following measures:

-    Flow division: discharge system of surface water, waste water, cooling water will be separated. Cooling water, rain water and overflow water will be not treated. Others will be treated appropriately to economize energy and reduce significantly water volume which needs to be treated.

-    All waste waters such as oil-contained water, chemical-contained water, domestic waste water, etc. will be treated to meet Vietnamese standard on environment. Because the waste water will be discharged into the Hau river which is a water supply source of life as well as aquatic organism protection, the National technical regulation QCVN 24:2009/BTNMT will be applied in design of waste water treatment system.

-    To unblock always drainage system, arrange soakage pits and residue collecting baskets at necessary sites. The residue will be collected and gathered together with domestic waste of the power plant. All will be transferred to dumping grounds according to contract with waste collection service of the local.

Noise

Following measureswill be applied:

-    To equip noise-killer (stopper for ear) for construction workers when they work at places with high noise level.

-    To build barriers in the project area since the beginning of the construction phase in order to reduce noise and dust from the project into surrounding area.

-   The project will arrange all noise sources such as arrange concrete mixing station, electric generator, etc. in appropriate places.

-    All construction activities are carried out in daytime and earlier 10pm. To limit construction activities causing noise in the evening (after 10pm), if have, the PMB will inform local people in order to avoid impact on health of local people.

-    To use methods and equipments with low noise and vibration levels

-    Vehicles for materials transportation are not allowed to cause noise. Drivers only honk if it is necessary.

-    Measures relating to construction activities of contractors will be included in tender document and considered in contractor choice.

5.      Environmental monitoring

Atmospheric emissions monitoring. Continuous emission monitoring of CO, SO2, NOx, particulates, oxygen content and temperature of flue gases will be carried out.

Ambient air quality monitoring. Continuous or periodic measurements of the following air quality indicators will be carried out: CO, NO2, NOX, SO2, …The plant will install an exhausted gas measurement and monitoringsystem (Ozsat) as:

-    General:

•    Supervision system is capable working condition at site and have selectable period from 1 to 24 hours and be able to self-diagnosis.

•   Equipment must synchronize with each other, including supervision/sampling devices, detecting heads, power sources, data processing devices, filters, fans to feed non-dust air to supervision devices.

•   Output signal of supervision device is DC current 4-24mA for DCS. The amplitude is proportional to smoke concentration.

•   Supervision shall display the gas concentration on a LCD or a normal screen which is based on a microprocessor and automatically standardizes zero point.

-     NOx/SO2monitor:

•   The plant shall be provided instrumentation to measure and monitor S02, NO and N02concentration. Measured concentration of gas shall be compensated for different working conditions and the absorption characteristics of elements of smoke, for example steam. Supervisors shall synchronize with gas-standardized cylinder, regulator and shall be placed at the inlet of smoke path to stack, behind smoke fan.

-     CO/CO2monitor:

•   Instruments that are used for supervising CO and C02shall include infrared analysis (sender and receiver). Gas concentration measured shall be compensated for different working conditions and for the absorption characteristics of other elements in smoke such as steam. Equipment shall be placed at a place that can be easily accessed on the path to stack.

-     Dust concentration monitor

•   Equipment to measure dust concentration is a monitor that be able tomeasure the fogginess of flue gas due to soot and dust. Dust concentration shall be compensated for different temperature mode and the absorption characteristics of smoke, such as team.

•   Three dust-concentration supervisors shall be provided and installed. One is placed smoke inlet of each precipitator and one on the common outlet of precipitators.

Table 3 Ambient environment monitoring

 

 

 

No.

 

Parameters

Monitoring

location

Devices

Number

of

sample

Frequency

A

CONSTRUCTION PHASE

 

A.1

Ambient air environment

 

 

-  Total dust (TSP)

-  so2

-NOx

-CO

Hydrocacbon

-  Noise

-  Construction site (concrete mixing station) (02 positions)

-  Road for material transportation

-  Around

residential area (02 positions)

-  Sampling device: DESAGE GS 312

(1 hr.); analysis method: Griss-Saltman according to ISO 6768/1995

-To measure amount according to Vietnamese standard 5067: 1995

-  Integral noise meter

05

6 months/ time in construction phase

 

A.2

Underground water

 

 

-pH

-SS

-Fe

-  As

-nh3

-no3

-no2

-  Coliforms

Underground water in housholds in around residential area (02 samples)

-  pH meter with glass electrode

-  To measure amount according to Vietnamese standard 5067: 1995

-  Atomic absorption spectrophotometry

-  Ultraviolet/ visible spectrophotometry

-    To filter by membrane and grow at 43 °C

02

6 months/ time in construction phase

 

A3

Surface water

 

 

-pH

-  Turbinity

-bod5

-COD

-  Oiai

-  Coliforms

River water in around project area (02 samples)

-  pH meter with glass electrode

-  Turbidity meter

-    Oxygen is dissolved after 5 days at 20°C

-  To oxidate by K2Cr207

-  Gas chromatography (Vietnamese standars 5070:1995)

-    To filter by membrane and grow at 43 °C

02

6

months/time

in

construction

phase

 

B

OPERATION PHASE

 

BA

Ambient air environment

 

 

-CO

-so2

~NOx

-  TSP -VOC

«pO

-  Humidity

-  Noise

-  DO storage

-  Boiler area

-  Stack base area

-  Plant precinct at wind direction

-  Port area

-  Coal storage area

-  Residential ares at wind direction (5 points)

-  Sampling device: DESAGE GS 312 (Ihr.); analysis method: Griss-Saltman according to ISO 6768/1995

-  To measure amount according to Vietnamese standard 5067: 1995

-  Thermometer

-  Humidity meter

-  Integral noise meter

11

6 months/ time

 

B.2

Underground water

 

 

-pH

-SS

-Fe

-  As

-nh3

-no3

-no2

-  Coliforms

Underground water in housholds in around residential area (03 samples)

(monitoring positions shown in figure 5-3)

-  pH meter with glass electrode

-  To measure amount according to Vietnamese standard 5067: 1995

-  Atomic absorption spectrophotometi7

-  Ultraviolet/ visible spectrophotometry

-To filter by membrane and grow at 43 °C

03

6 months/ time

 

B.3

Surface water

 

 

-pH

-  Turbinity -BOD5 -COD

-  Oil

-  T°

-  Coliforms

i

-  Cooling waste water intake canal

-  Cooling waste water discharge canal

-Position 100m far from cooling waste water outlet

-  Surface water in Hau river (2 samples)

(monitoring positions shown in

-  pH meter with glass electrode

-  Turbidity meter

-   Oxygen is dissolved after 5 days at 20°C

-  To oxidate by K2Cr207

-  Gas chromatography (Vietnamese standars 5070:1995)

-  Thermometer

-  To filter by membrane and grow at 43 °C

05

 

6 months/ time

1

 

B.4

Aquatic organism

 

 

Phytoplankt-on

Zooplankton

Zoobenthos

Hau river (upstream and downstream of the project area) (02 samples)

-  Phytoplankton: qualitative samples are collected by plankton net; 60 liter of water was filter for quantity samples.

-  Zooplankton: qualitative samples are collected by Juday plankton net, 60 liter of water was filter for quantity samples.

-  Zoobenthos: samples are collected by Petersen grab in area with 0.025m2. The samples after collecting are purified through a sieve 1 mm.

02

6 months/ time

 

                                   

 

 

 

Soil quality monitoring. Monitoring parameters: heavy metal, N, P, Ca, pH.

Monitoring positions: inside plant, residue disposal area, residential area around the plant, port area, conveyor and coal storage.

Number of sample: 05 samples

Frequency: 6 months/time

Process waste monitoring. Records of generated process wastes will be kept according to the regulations concerning types of waste. There will be registration sheets for hazardous waste and for process non-hazardous waste. Such data will be submitted to the county environmental office every three months.

Noise level monitoring. Noise levels will be monitored periodically for compliance with regulatory requirements.

6.      Public consultation

According to instruct of Decree No.80/2006/ND-CP dated on Aug. 9th, 2006 and No. 21/2008/ND-CP dated on Feb. 28th, 2008 of Government about guiding details of article of Law of environmental protection, Investor’s (Long Phu - Song Hau Power Project Management Board) official dispatch No 504/LPSH-KTKH dated on Aug. 17th, 2009 about "Suggestions about implement Song Hau 1 thermal plant project(enclosure EIA summary report of Song Hau I thermal plant)in which, the project’s impacts on environment and socio-economic, mitigation measures and others had been sent to Phu Huu A commune and received comment of People’s committee and Fatherland Front committee.

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