1
Introduction
1.1
Purpose of the Report
1.2
Structure of the Report
2
Project information
2.1
Background
2.2
General Site Description
2.3
Major Activities Undertaken
2.4
Project Organisation and Management Structure
2.5
Status of Environmental Approval Documents
3
Environmental Monitoring and Audit Requirements
3.1
Environmental Monitoring
3.1.1
Air Quality
3.1.2
Odour
3.2
Site Audit
3.2.1
Water Quality
3.2.2
Landscape and Visual
4
Monitoring Results
4.1
Air Quality
4.1.1
Operation Phase Monitoring
4.2
Odour
4.2.1
Operation Phase Monitoring
4.3
Water Quality
4.3.1
Operation Phase Monitoring
4.4
Waste Management
4.4.1
Operation Phase Monitoring
5
Site Audit
5.1
Environmental Site Audit
5.1.1
Operation Phase
5.2
Landscape and Visual Audit
6
Environmental Non-conformance and Deficiencies
6.1
Summary of Environmental Non-Compliance and
Deficiencies
6.2
Summary of Environmental Complaint
6.3
Summary of Environmental Summon and Successful
Prosecution
7
Future Key Issues
7.1
Key Issues for the Coming Month
8
Conclusions
Table 2.1 Summary
of Activities Undertaken in the Reporting Period
Table 2.2 Summary
of Environmental Licensing, Notification and Permit Status
Table 3.1 Sampling
and Laboratory Analysis Methodology
Table 3.2 Emission
Limit for CAPCS Stack
Table 3.3 Emission Limit for CHP Stack
Table 3.4 Emission
Limit for ASP Stack
Table 3.5 Emission
Limit for Standby Flaring Gas Unit
Table 3.6 Odour Intensity Level
Table 3.7 Action and
Limit Levels for Odour Nuisance
Table 3.8 Event and Action
Plan for Odour Monitoring
Table 3.9 Discharge
Limits for Effluent from the Outlet Chamber of the Effluent Storage Tank
Table 3.10 Discharge
Limits for Effluent from the Petrol Interceptors
Table 4.1 Hourly
Average of Parameters Recorded for CAPCS
Table 4.2 Hourly Average of Parameters Recorded for CHP
1
Table 4.3 Hourly Average of Parameters Recorded for CHP
2
Table 4.4 Hourly Average of Parameters Recorded for CHP
3
Table 4.5 Hourly Average of Parameters Recorded for ASP
Table 4.6 Hourly
Average of Parameters Recorded for the Standby Flaring Gas Unit
Table 4.7 Results of the Discharge Sample from the
Outlet Chamber of the Effluent Storage Tank
Table 4.8 Results
of the Discharge Sample from the Petrol Interceptor 1
Table 4.9 Results
of the Discharge Sample from the Petrol Interceptor 2
Table 4.10 Quantities of Waste Generated from the Operation of the
Project
Table 8.1
Exceedances for Stack Emissions
Table
8.2 Exceedance for Discharge Sample
EXECUTIVE
SUMMARY
The construction works
of No. EP/SP/61/10 Organic Resources Recovery Centre Phase 1 (the Project) commenced on 21 May
2015. This is the 94th monthly Environmental Monitoring and
Audit (EM&A) report presenting the EM&A works carried out during the
period from 1 to 31 March 2023 in accordance with the EM&A Manual.
Substantial completion of the construction works was confirmed on 3 December
2018. In the meantime, the operation phase EM&A programme had
commenced in March 2019. Substantial Completion in respect of substantial part
of the Works was confirmed on 24 February 2020. The construction phase
EM&A programme was completed in the end of February 2020.
Summary of Works
undertaken during the Reporting Month
Works undertaken in the
reporting month included:
· Operation of the Project, including organic waste
reception, and operation of the pre-treatment facilities, anaerobic digesters,
composting facilities, air pollution control systems, on-line emission
monitoring system for the Centralised Air Pollution Control Unit (CAPCS),
Co-generation Units (CHP)s and Ammonia Stripping Plant (ASP), and the
wastewater treatment plant;
· Adjustment of temperature curves on the CHP3;
· CHP2 was returned in operation instead of CHP3, by
moving the throttle valve from CHP3 to CHP2; and
· Back purging testing for CEMS.
Environmental Monitoring
and Audit Progress
Air Quality Monitoring
Non-compliance of
emission limits of VOCs (including methane) from CAPCS, NOx and SO2
from the CHPs, NOx, SO2, NH3 and HCl from ASP,
and HF from the Standby Flaring Gas Unit were recorded during the reporting
period. The cause of exceedances of VOCs (including methane) from CAPCS
is still under investigation. The exceedances of SO2 from CHPs
and the ASP occurred due to tripping of the de-sulphurisation system caused by
the failure of one of the columns of the system. The exceedance of NOx of CHPs, NOx, NH3
and HCl from ASP and HF from the Standby Flaring Gas Unit occurred due to
system instability caused by the ongoing performance optimisation of CHPs, the ASP and the Standby Flaring Gas Unit, resulting in a lowered
temperature of the system and the incomplete combustion of biogas.
Water Quality
Non-compliance of
discharge limit of Total Nitrogen from the Outlet Chamber of the Effluent
Storage Tank were recorded during the reporting period. The Contractor
found that an unexpected surge of Kjedahl Nitrogen in
Treated Effluent was observed, leading to the high Total Nitrogen level in the
Treated Effluent sampled on 9 March 2023.
Waste Management
Waste generated from the
operation of the Project includes chemical waste, waste generated from
pre-treatment process and general refuse.
No chemical waste was
collected by licenced waste collector from the operation of the Project.
682.0 tonnes of waste
generated from pre-treatment process from the operation of the Project was
disposed of at landfill. Among the recyclable waste generated from
pre-treatment process from the operation of the Project, 0.00 tonne of metals,
0.00 tonnes of papers/ cardboard packing and 0.00 tonne of plastics were sent
to recyclers for recycling during the reporting period.
Around 3.11 tonnes of
general refuse from the operation of the Project was
disposed of at landfill. Among the recycled general refuse from the
operation of the Project, 0.011 tonne of metals, 0.065 tonne of papers/
cardboard packing and 0.012 tonne of plastics were sent to recyclers for
recycling during the reporting period.
Findings of
Environmental Site Audit
A summary of the monitoring activities undertaken in
this reporting period is listed below:
|
· Joint Environmental Site Inspections
|
1 time
|
1 monthly joint environmental site inspection was
carried out by the representatives of the Contractor and the MT. The IEC
was also present at the joint inspections on 29 March 2023. The
environmental control/ mitigation measures (related to air quality, water
quality, waste (including land contamination prevention), hazard-to-life and
landscape and visual) recommended in the approved EIA Report and the EM&A
Manual were properly implemented by the Contractor during the reporting
month.
Environmental
Exceedance/Non-conformance/Compliant/Summons and Prosecution
Exceedances for the air emission
limits for the CAPCS, CHPs, ASP stacks and the Standby Flaring Gas Unit, and exceedances for the discharge sample from the
Outlet Chamber of the Effluent Storage Tank were recorded during the reporting
period.
No complaint/ summon/prosecution was received in this
reporting period.
Future Key Issues
Activities to be
undertaken in the next reporting month include:
· Operation of the Project; and
· CEMS QAL 2 pre-checks.
1
Introduction
ERM-Hong Kong, Limited (ERM) was appointed by OSCAR
Bioenergy Joint Venture (the Contractor) as the Environmental Team (ET) to
undertake the construction Environmental Monitoring and Audit (EM&A)
programme for the Contract No. EP/SP/61/10 of Organic Waste Treatment
Facilities Phase I, which the project name has been updated to
Organic Resources Recovery Centre (Phase I) (the Project) since November 2017. ERM was also appointed by the
Contractor to undertake the operation EM&A programme starting 1 March 2019.
1.1
Purpose of the
Report
This is the 94th EM&A report which
summarises the monitoring results and audit findings for the EM&A programme
during the reporting period from 1 to 31 March 2023.
1.2
Structure of the
Report
The structure of the report is as follows:
Section
1: Introduction
It details the scope and structure
of the report.
Section 2: Project
Information
It summarises the
background and scope of the Project, site description, project organisation and
status of the Environmental Permits (EP)/licences.
Section 3:
Environmental Monitoring and Audit Requirements
It summarises the environmental
monitoring requirements including monitoring parameters, programmes,
methodologies, frequency, locations, Action and Limit Levels, Event/Action
Plans, as well as environmental audit requirements as recommended in the EM&A
Manual and approved EIA report.
Section 4:
Monitoring Results
It summarises monitoring results of
the reporting period.
Section 5:
Site Audit
It summarises the audit findings of
the environmental as well as landscape and visual site audits undertaken within
the reporting period.
Section 6:
Environmental Non-conformance
It summarises any exceedance of
environmental performance standard, environmental complaints and summons
received within the reporting period.
Section 7:
Further Key Issues
It summarises the impact forecast
for the next reporting month.
Section 8:
Conclusions
2
Project information
2.1
Background
The Organic Resources Recovery Centre (ORRC) Phase I
development (hereinafter referred to as “the Project”) is to design, construct
and operate a biological treatment facility with a capacity of about 200 tonnes
per day and convert source-separated organic waste from commercial and
industrial sectors (mostly food waste) into compost and biogas through proven
biological treatment technologies. The location of the Project site is
shown in Annex A.
The environmental acceptability of the construction
and operation of the Project had been confirmed by findings of the associated
Environmental Impact Assessment (EIA) Study completed in 2009. The
Director of Environmental Protection (DEP) approved this EIA Report under the Environmental
Impact Assessment Ordinance (EIAO) (Cap. 499) in February 2010 (Register
No.: AEIAR-149/2010) (hereafter referred to as the approved EIA Report).
Subsequent Report on Re-assessment on Environmental Implications and Report on
Re-assessment on Hazard to Life Implications were completed in 2013,
respectively.
An Environmental Permit (EP) (No. EP-395/2010) was
issued by the DEP to the EPD (Project Team), the Permit Holder, on 21 June 2010
and varied on 18 March 2013 (No. EP-395/2010/A) and 21 May 2013 (No.
EP-395/2010/B), respectively. The Design Build and Operate Contract for
the ORRC Phase 1 (Contract No. EP/SP/61/10 Organic Resources Recovery Centre
(Phase 1) (the Contract)) was awarded to SITA Waste Services Limited, ATAL
Engineering Limited and Ros-Roca, Sociedad Anonima
jointly trading as the OSCAR Bioenergy Joint Venture (OSCAR or the
Contractor). A Further EP (No. FEP-01/395/2010/B) was issued by the DEP
to the OSCAR on 16 February 2015. Variation to both EPs (Nos.
EP-395/2010/B and FEP-01/395/2010/B) were made in December 2015. The latest
EPs, Nos. EP-395/2010/C and FEP-01/395/2010/C, were issued by the DEP on 21
December 2015.
Under the requirements of Condition 5 of the EP (No.
FEP-01/395/2010/C), an Environmental Monitoring and Audit (EM&A) programme
as set out in the approved EM&A Manual (hereinafter referred to as EM&A
Manual) is required to be implemented during the construction and operation of
the Project. ERM-Hong Kong, Ltd (ERM) has been appointed by OSCAR as the
Environmental Team (ET) for the construction phase EM&A programme and the
Monitoring Team (MT) for the operation phase EM&A programme for the
implementation of the EM&A programme in accordance
with the requirements of the EP and the approved EM&A Manual.
The construction works
commenced on 21 May 2015. The construction phase EM&A programme was
completed in the end of February 2020. The operation phase of the
EM&A programme commenced on 1 March 2019 ().
2.2
General Site
Description
The Project Site is located at Siu Ho Wan in North
Lantau with an area of about 2 hectares. The layout of the Project
Site is illustrated in Annex A.
The facility received an average of 155 tonnes and treated an average of 132.5
tonnes of source separated organic waste per day during the reporting month.
2.3
Major Activities
Undertaken
A summary of the major activities undertaken in the
reporting period is shown in Table 2.1.
Table 2.1
Summary of Activities Undertaken in the Reporting Period
|
Activities Undertaken
in the Reporting Period
|
|
·
Systems being operated – waste reception,
pre-treatment, CAPCS extraction, the digesters, the centrifuge, the
composting tunnels, the de-sulphurisation, the emergency flare, the CHPs, the
ASP and the biological waste water treatment plant
(155 t/d SSOW received);
· Adjustment of
temperature curves on the CHP3;
·
CHP2 was returned in operation instead of CHP3, by
moving the throttle valve from CHP3 to CHP2; and
·
Back purging testing for CEMS.
|
2.4
Project Organisation and Management Structure
The project organisation chart and contact details are
shown in Annex B.
2.5
Status of
Environmental Approval Documents
A summary of the valid permits, licences, and/or
notifications on environmental protection for this Project is presented in Table
2.2.
Table 2.2
Summary of Environmental Licensing, Notification and Permit Status
|
Permit/ Licences/ Notification
|
Reference
|
Validity Period
|
Remarks
|
|
Environmental
Permit
|
FEP-01/395/2010/C
|
Throughout the Contract
|
Permit granted on 21
December 2015
|
|
Effluent
Discharge Licence
|
WT00038391-2021
|
7
July 2021 – 30 June 2026
|
Approved
on 7 July 2021
|
|
Chemical Waste Producer Registration
|
WPN 5213-961-O2231-02
|
Throughout the implementation of the Project
|
Approved on 10 November 2017
|
|
Waste
Disposal Billing Account
|
Account
number: 702310
|
Throughout
the Contract
|
-
|
3
Environmental
Monitoring and Audit Requirements
3.1
Environmental
Monitoring
The air quality (including odour) monitoring to be
carried out during the commissioning and operation phase of the Project are
described below. Although water quality monitoring is not required for
the operation phase under the EM&A programme, there are water quality
monitoring requirement under the Water Discharge Licence of the plant under the
Water Pollution Control Ordinance (WPCO). As part of this EM&A
programme, the monitoring results will be reviewed to check the compliance with
the WPCO requirements.
3.1.1
Air Quality
According to the EM&A Manual and EP requirements,
stack monitoring are required during the commissioning
and operation phase of the Project.
On-line monitoring (using continuous environmental
monitoring system (CEMS) shall be carried out for the centralised air pollution
unit (CAPCS), cogeneration units (CHP) and the ammonia stripping plant (ASP)
during the commissioning and operation phase. The last calibration was
carried out on 14 February 2023.
The monitoring data is transmitted instantaneously to
EPD (Regional Office) by telemetry system.
When the on-line monitoring for certain parameter
cannot be undertaken, monitoring will be carried out using the following
methodology approved by the EPD.
Table
3.1
Sampling and Laboratory Analysis Methodology
|
Parameters
|
Method
|
Stacks
to be Monitored
|
|
Gaseous
and vaporous organic substances (including methane)
|
USEPA
Method 18
|
· CAPCS
· CHP
· ASP
|
|
Particulate
|
USEPA
Method 5
|
· CAPCS
· CHP
· ASP
|
|
Carbon
monoxide (CO)
|
USEPA Method 10
|
· CHP
· ASP
|
|
Nitrogen
oxides (NOx)
|
USEPA
Method 7E
|
· CHP
· ASP
|
|
Sulphur
dioxide (SO2);
|
USEPA
Method 6
|
· CHP
· ASP
|
|
Hydrogen
chloride (HCl)
|
USEPA
Method 26A
|
· CHP
· ASP
|
|
Hydrogen
fluoride (HF)
|
USEPA
Method 26A
|
· CHP
· ASP
|
|
Oxygen (O2);
|
USEPA
Method 3A
|
· CAPCS
· CHP
· ASP
|
|
Velocity
and Volumetric Flow
|
USEPA
Method 2
|
· CAPCS
· CHP
· ASP
|
|
Ammonia
(NH3)
|
USEPA CTM 027
|
· ASP
|
|
Odour
(including NH3 and H2S)
|
EN 13725
|
· CAPCS
|
|
Water
vapour content (continuous measurement of the water vapour content should not
be required if the sample exhaust gas is dried before the emissions are
analysed)
|
USEPA Method 4
|
· CAPCS
· CHP
· ASP
|
|
Temperature
|
USEPA Method 4
|
· CAPCS
· CHP
· ASP
|
With reference to the EM&A Manual, the air
emission of the stacks shall meet the following emission limits as presented in
Tables 3.2 to 3.5.
Table 3.2
Emission Limit for CAPCS Stack
|
Parameter
|
Emission
Level (mg/Nm3) (a)
|
|
VOCs
(including methane)
|
680
|
|
Dust (or Total Suspended
Particulates (TSP))
|
6
|
|
Odour (including
NH3 & H2S)
|
220 (b)
|
|
Notes:
(a)
Hourly
average concentration
(b)
The odour
unit is OU/Nm3
|
Table
3.3
Emission Limit for CHP Stack
|
Parameter
|
Maximum
Emission Level (mg/Nm3) (a) (b)
|
|
Dust (or
Total Suspended Particulates)
|
15
|
|
Carbon
Monoxide
|
650
|
|
NOx
|
300
|
|
SO2
|
50
|
|
NMVOCs (c)
|
150
|
|
VOCs (including methane) (d)
|
1,500
|
|
HCl
|
10
|
|
HF
|
1
|
|
Notes:
(a) All values refer to an oxygen content in the exhaust gas of
6% and dry basis.
(b) Hourly average concentration
(c) NMVOCs should be monitored by gas sampling and laboratory
analysis at an agreed interval. For the first 12 months (starting from
August 2019), monitoring should be carried out at quarterly intervals. The
monitoring frequency should then be reduced to half-yearly for next 12 months
(starting from August 2020). The monitoring of NMVOCs ended in August
2021.
(d) The VOCs emission limit include methane as biogas is adopted
as fuel in the combustion process.
|
Table 3.4 Emission Limit for
ASP Stack
|
Parameter
|
Maximum Emission Level (mg/Nm3) (a) (b)
|
|
Dust (or Total Suspended
Particulates)
|
5
|
|
Carbon Monoxide
|
100
|
|
NOx
|
200
|
|
SO2
|
50
|
|
VOCs (including methane) (c)
|
20
|
|
NH3
|
35
|
|
HCl
|
10
|
|
HF
|
1
|
|
Notes:
(a)
All
values refer to an oxygen content in the exhaust gas of 11% and dry basis.
(b)
Hourly
average concentration
(c)
The VOCs
emission limit include methane as biogas is adopted as fuel in the combustion
process.
|
Table
3.5 Emission Limit for Standby
Flaring Gas Unit ([2])
|
Parameter
|
Maximum
Emission level (mg/Nm3) (a) (b)
|
|
Dust (or
Total Suspended Particulates)
|
5
|
|
Carbon
Monoxide
|
100
|
|
NOx
|
200
|
|
SO2
|
50
|
|
VOCs
(including methane) (c)
|
20
|
|
HCl
|
10
|
|
HF
|
1
|
|
Notes:
(a) All values refer to an
oxygen content in the exhaust gas of 11% and dry basis.
(b) Hourly average
concentration
(c) The VOCs emission
limit include methane as biogas is adopted as fuel in the combustion process.
|
3.1.2
Odour
To determine the
effectiveness of the proposed odour mitigation measures and to ensure that the
operation of the ORRC1 will not cause adverse odour impacts, odour monitoring
of the CAPCS stack (see Section 3.1.1) and
odour patrol will be carried out.
Odour patrol shall be conducted by independent trained
personnel/ competent persons in summer months (i.e. from July to September) for
the first two operational years of ORRC1 at monthly intervals along an odour
patrol route at the Project Site boundary as shown in Annex A().
The perceived odour intensity is divided into 5
levels. Table 3.6 describes the odour intensity for different
levels.
Table
3.6
Odour Intensity Level
|
Level
|
Odour Intensity
|
|
0
|
Not detected. No odour perceived or an odour so weak that it
cannot be easily characterised
or described
|
|
1
|
Slight identifiable
odour, and slight
chance to have odour
nuisance
|
|
2
|
Moderate identifiable odour,
and moderate chance to have odour
nuisance
|
|
3
|
Strong identifiable,
likely to have odour nuisance
|
|
4
|
Extreme severe odour,
and unacceptable odour level
|
Table 3.7 shows the action level
and limit level to be used for odour patrol. Should any exceedance of the
action and limit levels occurs, actions in accordance with the event and action
plan in Table 3.8 should be carried out.
Table 3.7
Action and Limit Levels for Odour Nuisance
|
Parameter
|
Action
Level
|
Limit
Level
|
|
Odour
Nuisance (from odour patrol)
|
When one
documented compliant is received (a), or Odour Intensity of
2 is measured from odour patrol.
|
Two or more documented complaints
are received (a) within a week; or
Odour intensity of 3 or above is measured
from odour patrol.
|
|
Note:
(a)
Once the
complaint is received by the Project Proponent (EPD), the Project Proponent
would investigate and verify the complaint whether it is related to the
potential odour emission from the ORRC1 and its on-site wastewater treatment
unit.
|
Table 3.8
Event and Action Plan for Odour Monitoring
|
Event
|
Action
|
|
|
Person-in-charge of Odour Monitoring
|
Project
Proponent (a)
|
|
Action
Level
|
|
|
|
Exceedance
of action level (Odour Patrol)
|
1.
Identify source/reason of exceedance;
2. Repeat
odour patrol to confirm finding.
|
1. Carry
out investigation to identify the source/reason of exceedance.
Investigation should be completed within 2 weeks;
2. Rectify
any unacceptable practice;
3.
Implement more mitigation measures if necessary;
4. Inform
Drainage Services Department (DSD) or the operator of the Siu Ho Wan Sewage
Treatment Works (SHWSTW) if exceedance is considered to be
caused by the operation of the SHWSTW.
5. Inform
North Lantau Refuse Transfer Station (NLTS) operator if exceedance is considered to be caused by the operation of NLTS.
|
|
Exceedance
of action level (Odour Complaints)
|
1.
Identify source/reason of exceedance;
2. Carry
out odour patrol to determinate odour intensity.
|
1. Carry
out investigation and verify the complaint whether it is related to potential
odour emission from the nearby SHWSTW;
2. Carry
out investigation to identify the source/reason of exceedance.
Investigation should be completed within 2 weeks;
3. Rectify
any unacceptable practice;
4.
Implement more mitigation measures if necessary;
5. Inform
DSD or the operator of the SHWSTW if exceedance is
considered to be caused by the operation of the SHWSTW.
6. Inform
NLTS operator if exceedance is considered to be
caused by the operation of NLTS.
|
|
Limit
Level
|
|
|
|
Exceedance of limit level
|
1.
Identify source/reason of exceedance;
2. Inform EPD;
3. Repeat
odour patrol to confirm findings;
4.
Increase odour patrol frequency to bi-weekly;
5. Assess
effectiveness of remedial action and keep EPD informed of the results;
6. If
exceedance stops, cease additional odour patrol.
|
1. Carry
out investigation to identify the source/reason of exceedance.
Investigation should be completed within 2 week;
2. Rectify
any unacceptable practice;
3.
Formulate remedial actions;
4. Ensure
remedial actions properly implemented;
5. If
exceedance continues, consider what more/enhanced mitigation measures should
be implemented;
6. Inform
DSD or the operator of the SHWSTW if exceedance is
considered to be caused by the operation of the SHWSTW.
|
|
Note:
(a)
Project
Proponent shall identify an implementation agent.
|
3.2
Site Audit
Environmental mitigation measures (related to air
quality, water quality, waste, land contamination, hazard-to-life, and
landscape and visual) to be implemented during the operation phase of the
Project are recommended in the approved EIA Report and EM&A Manual and are
summarised in Annex C.
Monthly site audits for operation phase will be carried out to check the
implementation of these measures.
3.2.1
Water Quality
Compliance audits are to be undertaken to ensure that
a valid discharge licence has been issued by EPD prior to the discharge of
effluent from the operation of the Project site. The audit shall be
conducted to ensure that the effluent quality is in
compliance with the discharge licence requirements. As stipulated
in the operation phase discharge licence, effluent discharge are
to be sampled monthly from the outlet chamber of the Effluent Storage Tank,
while effluent discharge are to be sampled bi-monthly from the Petrol Interceptors.
The effluent quality shall meet the discharge limits as described in Table
3.9 and Table 3.10.
Table 3.9
Discharge Limits for Effluent from the Outlet Chamber of the Effluent Storage Tank
|
Parameters
|
Discharge
Limit (mg/L)
|
|
Flow Rate
(m3/day) (a)
|
645
|
|
pH (pH
units) (b)
|
6-10 (c)
|
|
Suspended
Solids (b)
|
800
|
|
Biochemical
Oxygen Demand (5 days, 20°) (b)
|
800
|
|
Chemical
Oxygen Demand (b)
|
2,000
|
|
Oil &
Grease (b)
|
40
|
|
Total
Nitrogen (b)
|
200
|
|
Total
Phosphorus (b)
|
50
|
|
Surfactants
(total) (b)
|
25
|
|
Notes:
(a) Flow rate is not a
parameter required to be monitored and reported by the Contractor in
accordance to Section B2 of the Effluent Discharge
Licence under the WPCO.
(b) Parameters required to
be monitored and reported by the Contractor in accordance to
Section B2 of the Effluent Discharge Licence under the WPCO.
(c) Range.
|
Table 3.10 Discharge Limits for Effluent
from the Petrol Interceptors
|
Parameters
|
Discharge
Limit (mg/L)
|
|
Flow Rate
(m3/day)
|
245 (a)
|
|
Suspended
Solids (b)
|
30
|
|
Chemical
Oxygen Demand (c)
|
80
|
|
Oil &
Grease (c)
|
20
|
|
Surfactants
(total) (b)
|
15
|
|
Notes:
(a) The surface runoff
flow rate limit was estimated by the overall yearly rainfall data. As
the actual flowrate from the petrol interceptors depends on the weather
condition instead of the performance of the petrol interceptor, monitoring
and reporting of this parameter is not required. Hence this parameter
is not reported in Table 4.8 and Table 4.9.
(b) Parameter not required
to be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
(c) Parameters required to
be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
|
3.2.2
Landscape and Visual
In accordance with EM&A Manual, the landscape and
visual mitigation measures shall be implemented.
For operation phase, site inspection shall be
conducted once a month for the first year of operation of the Project.
All measures as stated in the implementation schedule of the EM&A Manual
(see Annex C),
including compensatory planting, undertaken by both the Contractor and the
specialist Landscape Sub-Contractor during the first year of the operation
phase shall be audited by a Registered Landscape Architect (RLA) to ensure
compliance with the intended aims of the measures and the effectiveness of the
mitigation measures. After the one-year maintenance period, the landscape
maintenance and monitoring shall be carried out by the Contractor.
4
Monitoring Results
4.1
Air Quality
4.1.1
Operation Phase Monitoring
The concentrations of concerned air pollutants emitted
from the stacks of the CAPCS, CHP, and ASP during the reporting period are
monitored on-line by the continuous environmental monitoring system
(CEMS). During the reporting period, the standby flare operated on 28
March 2023.
With reference to the emission limits shown in Tables
3.2, 3.3, 3.4 and 3.5, the hourly average concentrations and
the number of exceedances of the concerned air emissions monitored for the
CAPCS, CHP, ASP and the Standby Flaring Gas Unit during this reporting period
are presented in Tables 4.1 to 4.6.
It should be noted that measurements recorded under
abnormal operating conditions, e.g. start up and stopping of stacks, unstable
operation, test runs and interference of sensor, are disregarded.
Table
4.1
Hourly Average of Parameters Recorded for CAPCS
|
Parameter
|
Range
of Hourly Average Conc. (mg/Nm3)
|
Emission
Limit (mg/Nm3)
|
Exceedance
Identified
|
Remarks
|
|
VOCs
(including methane)
|
0.00 –
1,714.29
|
680
|
Identified
(b)
|
The cause
of exceedances is still under investigation (c)
|
|
Dust (or TSP)
|
0.00 –
0.15
|
6
|
Nil
|
Nil
|
|
Odour (including
NH3 & H2S) (a)
|
0.00 –
85.76
|
220
|
Nil
|
Nil
|
|
Note:
(a)
The odour
unit is OU/Nm3.
(b)
Dates
with exceedances on VOCs (including methane) (number of exceedance on the
day) were identified on 2 (14), 3 (12), 4 (5), 5 (5), 6 (2), 7 (9), 8 (4), 9
(6), 17 (7), 18 (3), 19 (4), 20 (24), 21 (24), 22 (19), 23 (24), 24 (17), 25
(24), 26 (20), 27 (16), 28 (12), 29 (24), 30 (15) and 31 (15) March 2023.
(c)
The
reason for exceedance is still under investigation by the Contractor.
The investigation report will be updated once available.
|
Table
4.2
Hourly Average of Parameters Recorded for CHP 1
|
Parameter
|
Range of Hourly Average Conc. (mg/Nm3)
(a)
|
Max. Emission Limit (mg/Nm3)
|
Exceedance
Identified
|
Remarks
|
|
Dust (or TSP)
|
0 - 0
|
15
|
Nil
|
Nil
|
|
Carbon Monoxide
|
0 - 136
|
650
|
Nil
|
Nil
|
|
NOx
|
0 - 542
|
300
|
Identified (c)
|
System unstable (e.g. low efficiency, unstable column temperature)
|
|
SO2
|
0 - 133
|
50
|
Identified (d)
|
De-sulphurisation system tripped / Under Maintenance
|
|
VOCs (including methane) (b)
|
0 – 809
|
1,500
|
Nil
|
Nil
|
|
HCl
|
0 - 4
|
10
|
Nil
|
Nil
|
|
HF
|
0 - 1
|
1
|
Nil
|
Nil
|
|
Notes:
(a) All values refer to an
oxygen content in the exhaust gas of 6%
and dry basis.
(b) The VOCs emission
limit include methane as biogas is adopted as fuel in the combustion process.
(c) Dates with exceedances
on NOx (number of exceedance on the day) were identified on 1 (24), 2 (24), 3
(21), 4 (24), 5 (24), 6 (21), 7 (24), 8 (20), 9 (12), 10 (19), 11 (13), 12
(7), 13 (11), 14 (20), 15 (12), 16 (13), 17 (16), 18 (8), 19 (1), 20 (13), 21
(22), 22 (17), 23 (24), 24 (16), 25 (3), 26 (2), 27 (3), 28 (5), 29 (20), 30
(21) and 31 (20) March 2023.
(d) Date with exceedances
on SO2 (number of exceedance on the day)
were identified on 1 (19), 2 (24), 3 (12), 4 (23), 5 (24), 6 (18), 7 (16), 8
(3), 9 (6), 12 (1), 21 (2), 29 (14), 30 (21) and 31 (17) March 2023.
|
Table 4.3 Hourly Average of
Parameters Recorded for CHP 2
|
Parameter
|
Range
of Hourly Average Conc. (mg/Nm3) (a)
|
Max.
Emission Limit (mg/Nm3)
|
Exceedance
Identified
|
Remarks
|
|
Dust (or
TSP)
|
0 - 0
|
15
|
Nil
|
Nil
|
|
Carbon
Monoxide
|
0 – 125
|
650
|
Nil
|
Nil
|
|
NOx
|
0 – 460
|
300
|
Identified(c)
|
System
unstable (e.g. low efficiency, unstable column temperature)
|
|
SO2
|
0 – 141
|
50
|
Identified(d)
|
De-sulphurisation
system tripped / Under Maintenance
|
|
VOCs (including methane) (b)
|
0 – 667
|
1,500
|
Nil
|
Nil
|
|
HCl
|
0 – 3
|
10
|
Nil
|
Nil
|
|
HF
|
0 – 1
|
1
|
Nil
|
Nil
|
|
Notes:
(a) All values refer to an
oxygen content in the exhaust gas of 6%
and dry basis.
(b) The VOCs emission
limit include methane as biogas is adopted as fuel in the combustion process.
(c) Dates with exceedances
on NOx (number of exceedance on the day)
were identified on 24 (4), 25 (20), 26 (21), 27 (21), 28 (15), 29 (10), 30
(20) and 31 (17) March 2023.
(d) Dates with exceedances
on SO2 (number of exceedance on the day)
were identified on 24 (4), 25 (21), 26 (24), 27 (24), 28 (16), 29 (24), 30
(24) and 31 (18) March 2023.
|
Table 4.4 Hourly Average of
Parameters Recorded for CHP 3
|
Parameter
|
Range
of Hourly Average Conc. (mg/Nm3) (a)
|
Max.
Emission Limit (mg/Nm3)
|
Exceedances
Identified
|
Remarks
|
|
Dust (or
TSP)
|
0 – 3
|
15
|
Nil
|
Nil
|
|
Carbon
Monoxide
|
0 – 88
|
650
|
Nil
|
Nil
|
|
NOx
|
0 – 557
|
300
|
Identified(c)
|
System
unstable (e.g. low efficiency, unstable column temperature)
|
|
SO2
|
0 – 109
|
50
|
Identified(d)
|
De-sulphurisation
system tripped / Under Maintenance
|
|
VOCs (including methane) (b)
|
0 – 1,489
|
1,500
|
Nil
|
Nil
|
|
HCl
|
0 – 10
|
10
|
Nil
|
Nil
|
|
HF
|
0 – 1
|
1
|
Nil
|
Nil
|
|
Notes:
(a) All values refer to an
oxygen content in the exhaust gas of 6%
and dry basis.
(b) The VOCs emission
limit include methane as biogas is adopted as fuel in the combustion process.
(c) Date with exceedances
on NOx (number of exceedance on the day) were identified on 2 (4),
3 (18), 4 (9), 5 (23), 6 (19), 8 (23), 9 (23), 10 (24), 11 (24), 12 (24), 13
(23), 14 (23), 15 (24), 16 (19), 17 (21), 18 (18), 19 (24), 20 (10), 21 (22),
22 (21), 23 (24) and 24 (7) March 2023.
(d) Dates with exceedances
on SO2 (number of exceedance on the day) were identified on 2 (4),
3 (18), 4 (9), 5 (20), 6 (19), 8 (13), 9 (6), 10 (10), 11 (11), 12 (2), 13
(4), 14 (2), 16 (2), 17 (2), 18 (4), 19 (4), 20 (3), 21 (6), 22 (3), 23 (20)
and 24 (7) March 2023.
|
Table 4.5
Hourly Average of Parameters Recorded for ASP
|
Parameter
|
Range of Hourly Average Conc.
(mg/Nm3) (a)
|
Max. Emission Limit (mg/Nm3)
|
Exceedances
Identified
|
Remarks
|
|
Dust (or TSP)
|
0 – 5
|
5
|
Nil
|
Nil
|
|
Carbon Monoxide
|
0 – 95
|
100
|
Nil
|
Nil
|
|
NOx
|
0 – 1,129
|
200
|
Identified (c)
|
System unstable (e.g. low efficiency, unstable column temperature)
|
|
SO2
|
0 – 417
|
50
|
Identified(d)
|
De-sulphurization system tripped / Under
Maintenance
|
|
VOCs (including methane) (b)
|
0 – 20
|
20
|
Nil
|
Nil
|
|
NH3
|
0 – 797
|
35
|
Identified
(e)
|
System
unstable (e.g. low efficiency, unstable column temperature)
|
|
HCl
|
0 – 27
|
10
|
Identified
(f)
|
System
unstable (e.g. low efficiency, unstable column temperature)
|
|
HF
|
0 – 1
|
1
|
Nil
|
Nil
|
|
Notes:
(a) All values refer to an
oxygen content in the exhaust gas of 11% and dry basis.
(b) The VOCs emission
limit include methane as biogas is adopted as fuel in the combustion process.
(c) Dates with exceedances
on NOx (number of exceedances on the day) were identified on 1
(1), 2 (4), 3 (5), 4 (3), 5 (10), 6 (14), 7 (12), 8 (7), 9 (1), 11 (1), 12
(3), 13 (1), 14 (4), 15 (2), 16 (4), 18 (9), 19 (2), 20 (6), 21 (4), 22 (5),
23 (14), 24 (16), 25 (5), 26 (5), 27 (7), 28 (7), 29 (9), 30 (6) and 31 (6)
March 2023.
(d) Dates with exceedances
on SO2 (number of exceedances on the day) were identified on 3
(14), 4 (23), 5 (10), 6 (7), 7 (1), 11 (4), 12 (3), 13 (2), 15 (4), 16 (3),
19 (1), 20 (4), 21 (5), 22 (5), 23 (18), 24 (10), 25 (1), 26 (2), 27 (1), 28
(1), 29 (8), 30 (12) and 31 (2) March 2023.
(e) Dates with exceedances
on NH3 (number of exceedances on the day) were identified on 3
(5), 6 (1), 7 (2), 8 (2), 9 (9), 10 (6), 11 (3), 12 (10), 13 (2), 14 (5), 15
(10), 16 (12), 17 (4), 18 (3), 19 (22), 20 (22), 21 (14), 22 (15), 23 (22),
24 (20), 25 (22), 26 (17), 27 (17), 28 (14), 29 (10), 30 (9) and 31 (14)
March 2023.
(f) Date with exceedances
on HCl (number of exceedances on the day) was identified on 24 (1) March
2023.
|
Table 4.6 Hourly Average
of Parameters Recorded for the Standby Flaring Gas Unit
|
Parameter
|
Range of Hourly Average Conc. (mg/Nm3) (a)(c)
|
Max.
Emission Limit (mg/Nm3)
|
Exceedances
Identified
|
Remarks
|
|
Dust (or TSP)
|
0 – 0
|
5
|
Nil
|
Nil
|
|
Carbon Monoxide
|
0 – 0
|
100
|
Nil
|
Nil
|
|
NOx
|
0 – 30
|
200
|
Nil
|
Nil
|
|
SO2
|
0 – 0
|
50
|
Nil
|
Nil
|
|
VOCs (including methane) (b)
|
0 – 0
|
20
|
Nil
|
Nil
|
|
HCl
|
0 – 0
|
10
|
Nil
|
Nil
|
|
HF
|
0 – 4
|
1
|
Identified
(d)
|
System
unstable (e.g. low efficiency, unstable column temperature)
|
|
Notes:
(a) All values refer to an
oxygen content in the exhaust gas of 11% and dry basis.
(b) The VOCs emission
limit include methane as biogas is adopted as fuel in the combustion process.
(c) During the reporting
period, the standby flare operated on 28 March 2023.
(d) Date with exceedances
on HF (number of exceedances on the day) was identified on 28 (1) March 2023.
|
4.2.1
Operation Phase Monitoring
No odour patrol was required to be conducted for this
reporting period.
4.3
Water Quality
4.3.1
Operation Phase Monitoring
Effluent discharge was sampled from the outlet chamber
of the Effluent Storage Tank monthly and from the Petrol Interceptor(s)
bi-monthly as stipulated in the operation phase discharge licence. The
results of the discharge samples from the outlet chamber of the Effluent Storage
Tank are recorded in Table 4.6 and the results from the Petrol
Interceptors are recorded in Tables 4.7 – 4.9.
Table
4.7
Results of the Discharge Sample from the Outlet
Chamber of the Effluent Storage Tank
|
Parameters
|
Discharged Effluent Concentration (mg/L)
|
Discharge Limit (mg/L)
|
Compliance with Discharge Limit
|
|
Flow Rate (m3/day) (a)
|
44 – 244 (e)
|
645
|
Yes
|
|
pH (pH units) (b)
|
8.01 – 8.4 (e)
|
6-10 (c)
|
Yes
|
|
Suspended Solids (b) (d)
|
113 (d)
|
800
|
Yes
|
|
Biochemical Oxygen Demand (5 days, 20°) (b) (d)
|
14 (d)
|
800
|
Yes
|
|
Chemical Oxygen Demand
(b) (d)
|
984 (d)
|
2,000
|
Yes
|
|
Oil & Grease (b) (d)
|
<5 (d)
|
40
|
Yes
|
|
Total Nitrogen (b) (d)
|
430 (d)
|
200
|
No(f)
|
|
Total Phosphorus (b) (d)
|
21.1 (d)
|
50
|
Yes
|
|
Surfactants (total) (b) (d)
|
<1.0 (d)
|
25
|
Yes
|
|
Notes:
(a) Parameter not required
to be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
(b) Parameters required to
be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
(c) Daily Range.
(d) Effluent sample
collected on 9 March 2023.
(e) Data collected daily.
(f) An unexpected surge of
Kjedahl Nitrogen in Treated Effluent was observed,
leading to the high Total Nitrogen level in the Treated Effluent sampled on 9
March 2023.
|
Table 4.8
Results of the Discharge Sample from the Petrol Interceptor 1
|
Parameters
|
Discharged Effluent Concentration (mg/L)
|
Discharge Limit (mg/L)
|
Compliance with Discharge Limit
|
|
Suspended Solids (b)
|
- (a)
|
30
|
N/A
|
|
Chemical Oxygen Demand (c)
|
- (a)
|
80
|
N/A
|
|
Oil & Grease (c)
|
- (a)
|
20
|
N/A
|
|
Surfactants (total) (b)
|
- (a)
|
15
|
N/A
|
|
Notes:
(a) No sampling was
required in March 2023.
(b) Parameter not required
to be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
(c) Parameters required to
be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
|
Table
4.9
Results of the Discharge Sample from the Petrol Interceptor 2
|
Parameters
|
Discharged Effluent Concentration (mg/L)
|
Discharge Limit (mg/L)
|
Compliance with Discharge Limit
|
|
Suspended Solids (b)
|
- (a)
|
30
|
N/A
|
|
Chemical Oxygen Demand (c)
|
- (a)
|
80
|
N/A
|
|
Oil & Grease (c)
|
- (a)
|
20
|
N/A
|
|
Surfactants (total) (b)
|
- (a)
|
15
|
N/A
|
|
Notes:
(a) No sampling was
required in March 2023.
(b) Parameter not required
to be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
(c) Parameters required to
be reported in accordance to Section B2 of the
Effluent Discharge Licence under the WPCO.
|
4.4
Waste Management
4.4.1
Operation Phase Monitoring
Wastes generated from the operation of the Project
include chemical waste, wastes generated from pre-treatment process and general
refuse ().
Reference has been made to the Monthly Summary Waste Flow Table prepared by the
Contractor (see Annex D).
With reference to the relevant handling records and trip tickets of this
Project, the quantities of different types of waste generated from the
operation of the Project in the reporting month are summarised in Table 4.10.
Table 4.10
Quantities of Waste Generated from the Operation of the Project
|
Month
/ Year
|
Chemical Waste
|
Waste Generated from
Pre-treatment Process
|
General Refuse
|
|
|
Disposal of at CWTC
|
Disposed of at Landfill (a)
|
Recycled (b)
|
Disposed of at Landfill (a)
|
Recycled (c)
|
|
March
2023
|
0 L (d)
|
682.0 tonnes
|
0 tonnes
|
3.11 tonnes (e)
|
0.088 tonnes
|
|
Notes:
(a)
Waste
generated from pre-treatment process and general refuse other than chemical
waste and recyclables were disposed of at NENT Landfill by sub-contractors.
(b)
Among
waste generated from pre-treatment process, 0.00 tonne of metals, 0.00 tonnes
of papers/ cardboard packing and 0.00 tonne of plastics were sent to
recyclers for recycling during the reporting period.
(c)
Among
general refuse, 0.011 tonnes of metals, 0.065 tonnes of papers/ cardboard
packing and 0.012 tonnes of plastics were sent to recyclers for recycling
during the reporting period.
(d)
No
chemical waste was disposed of at CWTC in March 2023.
(e)
It was
assumed that four 240-litre bins filled with 80% of general refuse were
collected at each collection. The general refuse density was assumed to
be around 0.15 kg/L.
|
5
Site Audit
5.1
Environmental Site Audit
5.1.1
Operation Phase
The monthly inspection
for the operation phase of the Project on 29 March 2023 covered the
operation phase environmental site audit. Joint site inspection was
conducted by representatives of the Contractor, IEC, and the MT on 29 March
2023 as required for the operation of the Project.
The audits checked the
implementation of the recommended mitigation measures for air quality,
landscape and visual, water quality, waste (land contamination) and
hazard-to-life stated in the Implementation Schedule (see Annex C).
Key observations during the reporting period are
summarised as follows:
29 March 2023
·
No particular observation during this inspection.
Other than the above observations, the Contractor has
implemented environmental mitigation measures recommended in the approved EIA
Report and EM&A Manual.
5.2
Landscape and
Visual Audit
Inspection of the
landscape and visual mitigation measures for the operation phase of the Project
was performed on 29 March 2023.
It was confirmed that
the necessary landscape and visual mitigation measures during the operation
phase as summarised in Annex C
were generally implemented by the Contractor. No specific observation was
found during the joint site inspection on 29 March 2023. No
non-compliance in relation to the landscape and visual mitigation measures was
identified during the site audits in this reporting period and therefore no
further actions are required. The ET/MT will keep track of the EM&A
programme to check compliance with environmental requirements and the proper
implementation of all necessary mitigation measures.
6
Environmental
Non-conformance and Deficiencies
6.1
Summary of
Environmental Non-Compliance and Deficiencies
Non-compliance of emission limits of VOCs (including
methane) from CAPCS, NOx and SO2 from the CHPs, NOx,
SO2, NH3 and HCl from ASP, HF from the Standby Flaring
Gas Unit, and non-compliance of discharge limits of Total Nitrogen from the
Outlet Chamber of the Effluent Storage Tank were recorded during the reporting
period.
The Contractor has reviewed the organic waste
treatment processes (i.e. waste reception, waste pre-treatment, anaerobic
digesters, and composting processes) and found that they were operated normally
during the reporting period. The Contractor has investigated the
de-sulphurisation system, CHPs the ASP and the Standby Flaring Gas Unit, the potential causes
for the exceedance were identified.
The Contractor has also carried out investigation on
the Outlet Chamber of the Effluent Storage Tank, and
found that an unexpected surge of Kjeldahl Nitrogen was observed in the Treated
Effluent sampled on 9 March 2023, leading to the high Total Nitrogen
level.
The investigation reports of the above exceedance are
presented in Annex F.
The reason for CAPCS exceedances is under Contractor’s investigation. The
investigation report will be updated once available.
6.2
Summary of
Environmental Complaint
No complaint was
received during the reporting period.
6.3
Summary of
Environmental Summon and Successful Prosecution
No summon/prosecution
was received during the reporting period. The cumulative
summons/prosecution log is shown in Annex E.
7
Future Key Issues
7.1
Key Issues for
the Coming Month
Activities to be undertaken for the coming reporting
period are:
·
Operation
of the Project; and
·
CEMS QAL 2
pre-checks.
8
Conclusions
This EM&A Report presents the EM&A programme
undertaken during the reporting period from 1 to 31 March 2023 in
accordance with EM&A Manual (Version F) and requirements of EP
(FEP-01/395/2010/C).
For the operation phase, exceedances of the emission
limits for the CHPs and the ASP stack monitoring were recorded under normal
operating conditions during the reporting period (see Table 8.1).
Table 8.1 Exceedances for Stack
Emissions
|
Stack
|
Exceedances
During the Reporting Period
|
|
Centralised Air
Pollution Unit (CAPCS)
|
· Exceeded emission
limit of VOCs (including methane) on 2, 3, 4, 6, 7, 8, 9, 17, 18, 19, 20, 21,
22, 23, 24, 25, 26, 27, 28, 29, 30 and 31 March 2023.
|
|
Cogeneration Unit 1
(CHP 1)
|
· Exceeded emission
limit of NOx on 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 and 31 March 2023.
· Exceeded emission
limit of SO2 on 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 21, 29, 30 and 31
March 2023.
|
|
Cogeneration Unit 2
(CHP 2)
|
· Exceeded emission
limit of NOx on 24, 25, 26, 27, 28, 29, 30 and 31 March 2023.
· Exceeded emission
limit of SO2 on 24, 25, 26, 27, 28, 29, 30 and 31 March 2023.
|
|
Cogeneration Unit 3
(CHP 3)
|
· Exceeded emission
limit of NOx on 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16,
17, 18, 19, 20, 21, 22, 23 and 24 March 2023.
· Exceeded emission
limit of SO2 on 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 16, 17,
18, 19, 20, 21, 22, 23 and 24 March 2023.
|
|
Ammonia Stripping
Plant (ASP)
|
· Exceeded emission
limit of NOx on 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 and 31 March 2023.
· Exceeded emission
limit of SO2 on 3, 4, 5, 6, 7, 11, 12, 13, 15, 16, 19, 20, 21, 22, 23, 24,
25, 26, 27, 28, 29, 30 and 31 March 2023.
· Exceeded emission
limit of NH3 (number of exceedances on the day) were identified on
3, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
25, 26, 27, 28, 29, 30 and 31 March 2023.
· Exceeded emission
limit of HCl on 24 March 2023.
|
|
Standby Flaring Gas
Unit
|
· Exceeded emission
limit of HF on 28 March 2023.
|
Non-compliance of emission limits of VOCs (including
methane) from CAPCS, NOx and SO2 from the CHPs, HF from
the Standby Flaring Gas Unit, and NOx, SO2, NH3
and HCl from ASP were recorded during the reporting period. The cause of
the exceedances of VOCs (including methane) is still under investigation.
The exceedances of SO2 from CHPs and the ASP occurred due to
tripping of the de-sulphurisation system caused by the failure of one of the
columns of the system. The exceedance of NOx of CHPs, NOx, NH3
and HCl from ASP and HF from the Standby Flaring Gas Unit occurred due to
system instability caused by the ongoing performance optimisation of CHPs, ASP and Standby Flaring Gas Unit, resulting in a lowered
temperature of the system and the incomplete combustion of biogas.
Table
8.2 Exceedances for Effluent Discharge
|
Effluent
discharge Point
|
Exceedances
During the Reporting Period
|
|
Outlet Chamber of the
Effluent Storage Tank
|
· Exceeded discharge
limit of Total Nitrogen on 9 March 2023
|
Non-compliance of discharge limit of Total Nitrogen
from the Outlet Chamber of the Effluent Storage Tank were recorded during the
reporting period. The Contractor found that an unexpected surge of Kjedahl Nitrogen in Treated Effluent was observed, leading
to the high Total Nitrogen level in the Treated Effluent sampled on 9 March
2023.
The environmental control /mitigation measures related
to air quality, water quality, waste (including land contamination prevention),
hazard-to-life and landscape and visual recommended in the approved EIA Report
and the EM&A Manual were properly implemented by the Contractor during the
reporting month.
Monthly landscape and visual monitoring were conducted
in the reporting period. The necessary landscape and visual mitigation
measures recommended in the approved EIA Report were generally implemented by
the Contractor.
No complaint/summon/prosecution was received.