1.1
Background
In support of the Government of the Hong Kong Special Administrative
Region (HKSARG)’s regional air quality improvement initiative, the Castle Peak
Power Company Limited (CAPCO), a joint venture between CLP Power Hong Kong
Limited (CLP Power) and Exxon Mobil Energy Limited (EMEL), proposes to install
additional emissions control facilities on their Castle Peak Power Station “B”
Units (CPB) to further reduce air emissions from the operations of these units.
CPB units use pulverised coal
as the primary fuel. All CPB units
were commissioned during 1986 to 1990 with a unit size of 677 MW (gross).
It is CAPCO’s objective to
responsibly manage the environmental impacts of their operations and to meet
HKSARG's environmental license requirements while providing reliable
electricity supply. Since its full
commissioning, CPB has been retrofitted with low nitrogen oxide (NOx) burners for
the boilers, flue gas conditioning systems, and upgrades to the electrostatic
precipitators (ESPs) in addition to boiler optimisation improvements in recent
years for improved particulates and NOx control. As a result of these measures and
together with the introduction of natural gas in the mid 1990s and increased
utilisation of ultra low sulphur coal, emissions of NOx, sulphur
dioxide (SO2)
and
particulates from all CAPCO facilities have already been reduced by 77%, 44%
and 70% respectively over the 1990 to 2005 period when the total electricity
demand has grown by about 80%.
Based on the CPB emissions
control project description included in CAPCO and CLP Power’s 2005 Financial
Plan which was accepted by HKSAR Government, the following additional emissions
control facilities are currently proposed for implementation at CPB:
·
Selective
Catalytic Reduction (SCR) for NOx reduction; and
·
Limestone
Flue Gas Desulphurisation (LS FGD) for SO2 reduction.
While there are several other emission control technologies available
for NOx reduction, final NOx control facility will be
subject to design optimisation. For
the purpose of this EIA Study, SCR has been selected as the most conservative
process with respect to environmental impact. This is due to the fact that the SCR
system encompasses the facilities and elements associated with the other available
NOx reduction technologies.
A power station is a designated project (DP) under Category D (Energy
Supply), Item D.1 (Public Utility Electricity Power Plant) of Schedule 2, Part
I under the Environmental Impact
Assessment Ordinance (EIAO)(Cap
499). As Castle Peak Power Station
(CPPS) has been in operation before the EIAO
came into force, it is exempted under Section
9(2) of the EIAO.
As indicated in Section 1.3 of
EIA Study Brief No. ESB 134/2005 (the
Study Brief) issued for the above-mentioned
Emissions Control Project (the Project), the Project is a Material Change, as
defined under Section 9 (4) of the EIAO, as a result of the changes introduced by the SCR and the LS
FGD operations to the types and quantities of wastes, emissions and
effluents. The Project also
includes the following elements which would qualify as DPs in their own right
under Schedule 2 of the EIAO:
· demolition of the CPB
4,600-tonne Fuel Oil Day Tank (FODT) [Item 16 (Decommissioning of a store for oil with a storage
capacity exceeding 200 tonnes) of Schedule 2, Part II];
· construction and operation of urea storage
facility, dissolvers, urea solution storage tanks and urea-to-ammonia reactors
for SCR operations [Category K (Industrial Activities), Item K.6 (A chemical
plant with a storage capacity of more than 500 tonnes and in which substances
are processed or produced) of Schedule 2, Part I]; and
·
construction
and operation of gypsum storage and handling facilities for FGD operations
[Category G (Waste Storage, Transfer and Disposal Facilities), Item G.6 (A
waste disposal facility for gypsum) of Schedule 2, Part I].
1.2
Site Location and Site History
The Castle Peak Power Station (CPPS) is located at Tap Shek Kok in Tuen
Mun,
1.3
Objectives of the Study
This EIA Study is conducted in accordance with the Study Brief. The
objectives of the EIA Study, as stated in the Study Brief, are:
·
to
describe the Project and associated works together with the requirements for
carrying out the Project;
·
to
identify and describe elements of community and environment likely to be
affected by the Project and/or likely to cause adverse impacts to the Project,
including natural and man-made environment and the associated environmental
constraints;
·
to
provide information on the consideration of alternatives to avoid and minimize
potential environmental impacts to ecologically sensitive areas and other
sensitive uses; to compare the environmental benefits and drawbacks of each of
different options; to provide reasons for selecting the preferred option(s) and
to describe the part environmental factors played in the selection of preferred
option(s);
·
to
identify and quantify emission sources and determine the significance of
impacts on sensitive receivers and potential affected uses;
·
to
identify and quantify any potential landscape and visual impacts and to propose
measures to mitigate these impacts;
·
to
identify and quantify any potential losses or damage to flora, fauna and
natural habitats and to propose measures to mitigate these impacts;
·
to
propose the provision of mitigation measures so as to minimise pollution,
environmental disturbance and nuisance during construction and operation of the
Project;
·
to
investigate the feasibility, practicability, effectiveness and implications of
the proposed mitigation measures;
·
to
identify, predict and evaluate the residual environmental impacts (ie after
practicable mitigation) and the cumulative effects expected to arise during the
construction and operation phases of the Project in relation to the sensitive
receivers and potential affected uses;
·
to
identify, assess and specify methods, measures and standards, to be included in
the detailed design, construction and operation of the Project which are
necessary to mitigate these environmental impacts and cumulative effects and
reduce them to acceptable levels;
·
to
investigate the extent of the secondary environmental impacts that may arise
from the proposed mitigation measures and to identify constraints associated
with the mitigation measures recommended in the EIA study, as well as the
provision of any necessary modification; and
·
to
design and specify environmental monitoring and audit requirements to ensure
the effective implementation of the recommended environmental protection and
pollution control measures.
The Project has no impact on cultural heritage,
agriculture and fisheries, and therefore these aspects are not assessed in the
EIA Study.
1.4
Approach to the Study
The assessments in this EIA Study are conducted using well-proven and
internationally accepted methods based on the worst-case conditions associated
with the construction and operation of the Project.
1.5
Structure of the Report
The remainder of this EIA Report is organised as follows:
·
Section 2 presents a description of the Project and the
considerations given to alternatives in the process of choosing the preferred
option;
·
Section 3 presents the air quality assessment for the Project;
·
Section 4 presents the noise assessment for the Project;
·
Section 5 presents the water quality assessment for the
Project;
·
Section 6 discusses the waste management issues associated with
the Project;
·
Section 7 presents the land contamination assessment undertaken
for the Project;
·
Section 8 discusses the ecological assessment for the Project;
·
Section 9 provides a visual illustration for the Project;
·
Section 10 outlines the requirements for environmental
monitoring and audit during the construction and operation of the Project and
presents an environmental mitigation implementation schedule; and
·
Section 11 concludes the report with a summary of the
environmental outcomes associated with the construction and operation of the
Project.