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 32^nd Quarterly EM&A report which summarises the monitoring results and audit findings for the EM&A programme during the reporting period from 1 March 2023 to 31 May 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 operation phase of the EM&A programme commenced on 1 March 2019 ([1]). The construction phase EM&A programme was completed in the end of February 2020.

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 127.97 to 155 tonnes and treated an average of 108.65 to 132.5 tonnes of source separated organic waste per day during the reporting period.

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 desulphurisation, the emergency flare, the CHPs, the ASP and the biological wastewater treatment plant (about 127.97 – 155 t/d SSOW input);

· Adjustment of temperature curves on the CHP3;

· CHP2 was returned in operation instead of CHP3, by moving the throttle valve from CHP3 to CHP2;

· Back purging testing for CEMS;

· VOC calibration for CAPCS stack;

· Emergency repair of chemical scrubber fan;

· Preparation for QAL 2 on the CEMS system (April 2023 – May 2023);

· SBR 3 and ASP plate heat exchanger cleaning;

· Fire Services System annual inspection;

· CEMS maintenance;

· QAL 2 testing with 3rd Party Lab was conducted for MCS 1 and MCS 2; and

· Replacement of membrane diffusers for all of the SBR Tanks of the Wastewater Treatment Plant was completed.

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
Notification of Construction Works under the Air Pollution Control (Construction Dust) Regulation	Ref No. 386715	Throughout the Contract	-
Effluent Discharge License	WT00038391-2021	7 July 2021 – 30 June 2026	Approved on 7 July 2021
Chemical Waste Producer Registration	WPN 5213-961-O2231-01	Throughout the Contract	Approved on 29 April 2015
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 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 is required during the 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 operation phase. The last calibration was carried out from 24 to 26 April 2023; and the last maintenance was carried out from 1 to 4 May 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 (NO_x)	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
NO_x	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). (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
NO_x	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 odour, 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 occur, 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.

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; and 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; and 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; and 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. Under Effluent Discharge Licence WT00038391-2021 (effective from July 2021), 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 Effluent Storage Tank (as stipulated in WT00038391-2021)

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 with Section B2 of the Effluent Discharge Licence under the WPCO. (b) Parameters required to be monitored and reported by the Contractor in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (c) Range.

Table 3.10 Discharge Limits for Effluent from the Petrol Interceptor(s) (as stipulated in TW00038391-2021)

Parameters	Discharge Limit (mg/L)
Flow Rate (m³/day)^(a)	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 4.10 and Table 4.11. (b) Parameter not required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (c) Parameters required to be reported in accordance with 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.

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 and 3 May 2023. The standby flare did not operate during April 2023.

With reference to the emission limits shown in Tables 3.2, 3.3 and 3.4, the hourly average concentrations and the number of exceedances of the concerned air emissions monitored for the CAPCS, CHP and ASP during this reporting period are presented in Tables 4.1 to 4.5.

It should be noted that measurements recorded under abnormal operating conditions, e.g., start up and stopping of stacks and unstable operation, as well as 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 – 1714.29	680	Identified ^(b)	Faulty sensor in March and April
Dust (or TSP)	0.00 – 0.22	6	Nil	Nil
Odour (including NH₃ & H₂S) ^(a)	0.00 – 154.07	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; 1 (24), 2 (19), 3 (7), 4 (24), 5 (24), 6 (24), 7 (10), 10 (20), 11 (24), 12 (8), 13 (15), 14 (24), 15 (24), 16 (9), 17 (23), 18 (24), 19 (24), 20 (24), 21 (24), 22 (24), 23 (24), 24 (24), 25 (19), 26 (19), 27 (24), 28 (19), 29 (24) and 30 (8) April 2023.

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 - 132	15	Identified ^(c)	System unstable (e.g., low efficiency, unstable column temperature)
Carbon Monoxide	0 - 628	650	Nil	Nil
NO_x	0 – 704	300	Identified ^(d)	System unstable (e.g., low efficiency, unstable column temperature)
SO₂	0 – 1848	50	Identified ^(e)	De-sulphurisation system tripped / Under Maintenance
VOCs (including methane)^(b)	0 - 12,808	1,500	Identified ^(f)	System unstable (e.g., low efficiency, unstable column temperature)
HCl	0 - 9	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 includes methane as biogas is adopted as fuel in the combustion process. (c) Date with exceedances on Dust (number of exceedances on that day) was identified on 8 (1) May 2023. (d) Dates with NO_x exceedances (number of exceedances 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; 1 (22), 2 (13), 3 (12), 4 (9), 5 (5), 6 (1), 7 (2), 8 (5), 9 (2), 12 (1), 13 (12), 14 (3), 15 (4), 17 (3), 18 (2), 19 (5), 20 (3), 21 (18), 22 (24), 23 (24), 24 (16), 25 (20), 26 (15), 27 (4), 28 (17), 29 (12) and 30 (23) April 2023; 1 (21), 2 (17), 3 (12), 4 (12), 5 (12), 6 (9), 7 (5), 8 (1), 10 (5), 11 (8), 13 (11), 14 (12), 15 (17), 16 (5), 17 (16), 18 (10), 19 (21), 20 (21), 21 (18), 22 (13), 23 (11), 24 (17), 25 (1), 30 (7) and 31 (1) May 2023. (e) Dates with SO₂ exceedances (number of exceedances 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; 1 (14), 2 (2), 9 (2), 12 (1), 13 (11), 14 (3), 15 (4), 17 (3), 18 (2), 19 (5), 20 (3), 21 (18), 22 (24), 23 (24), 24 (18), 25 (22), 26 (15), 27 (2) and 28 (9) April 2023 ;1 (1), 2 (1), 3 (4), 4 (3), 5 (5), 8 (1), 11 (6), 15 (1), 17 (2), 18 (1), 19 (7), 20 (13), 21 (1), 22 (9), 23 (9), 24 (17), 25 (1), 30 (2) and 31 (1) May 2023. (f) Dates with exceedances on VOC (number of exceedances on the day) was identified on 8 (1) May 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 – 183	15	Identified^(c)	System unstable (e.g., low efficiency, unstable column temperature)
Carbon Monoxide	0 – 328	650	Nil	Nil
NO_x	0 – 571	300	Identified ^(d)	System unstable (e.g., low efficiency, unstable column temperature)
SO₂	0 – 141	50	Identified ^(e)	De-sulphurisation system tripped / Under Maintenance
VOCs (including methane)^(b)	0 – 1483	1,500	Nil	Nil
HCl	0 – 18	10	Identified ^(f)	System unstable (e.g., low efficiency, unstable column temperature)
HF	0 – 7	1	Identified^(g)	System unstable (e.g., low efficiency, unstable column temperature)
Notes: (a) All values refer to an oxygen content in the exhaust gas of 6% and dry basis. (b) The VOCs emission limit includes methane as biogas is adopted as fuel in the combustion process. (c) Dates with exceedances on dust (number of exceedances on that day) were identified on 17 (1) and 18 (1) April 2023; 8 (1) May 2023. (d) Dates with NOx exceedances (number of exceedances 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; 1 (11), 2 (21), 3 (17), 4 (23), 5 (22), 6 (22), 7 (15), 8 (24), 9 (17), 10 (24), 11 (19), 12 (9), 13 (9), 14 (11), 15 (14), 16 (11), 17 (23), 18 (21), 19 (3), 20 (19), 21 (16), 22 (17), 23 (16), 24 (8), 25 (6), 26 (19), 27 (11), 28 (21), 29 (15) and 30 (1) April 2023; 1 (20), 2 (16), 3 (3), 4 (3), 5 (4), 6 (12), 7 (4), 8 (7), 9 (1), 10 (9), 11 (24), 12 (24), 13 (24), 14 (24), 15 (20), 16 (14), 17 (15), 18 (10), 19 (2), 20 (24), 21 (24), 22 (11), 23 (24), 24 (24), 25 (24), 26 (24), 27 (17), 28 (8), 29 (6), 30 (1) and 31 (5) May 2023. (e) Dates with SO₂ exceedances (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; 1 (8), 2 (17), 3 (16), 4 (13), 5 (10), 6 (24), 7 (18), 8 (22), 9 (16), 10 (24), 11 (24), 12 (24), 13 (22), 14 (24), 15 (21), 16 (24), 17 (20), 18 (22), 19 (2), 20 (10), 21 (11), 22 (6), 23 (8), 24 (18), 25 (10), 26 (4), 27 (1), 28 (3), 29 (11) and 30 (17) April 2023; 1 (4), 2 (4), 4 (2), 5 (5), 6 (1), 8 (6), 9 (20), 10 (3), 12 (1), 16 (1), 18 (1), 28 (3), 29 (3), 30 (1) and 31 (6) May 2023. (f) Date with HCl exceedance (number of exceedances on that day) was identified on 17 (1) and 18 (1) April 2023. (g) Dates with exceedances on HF (number of exceedances on that day) were identified on 17 (1) April 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 – 4	15	Nil	Nil
Carbon Monoxide	0 – 88	650	Nil	Nil
NO_x	0 – 589	300	Identified ^(c)	System unstable (e.g., low efficiency, unstable column temperature)
SO₂	0 – 109	50	Identified ^(d)	Desulphurisation 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 includes methane as biogas is adopted as fuel in the combustion process. (c) Dates with NO_x exceedances (number of exceedances on the day) were identified on2 (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; 21 (4), 22 (12), 23 (4), 24 (1), 25 (14), 26 (6), 27 (4), 28 (4), 29 (2) and 30 (15) May 2023. (d) Dates with SO₂ exceedances (number of exceedance on the day) was 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; 21 (4), 22 (6), 25 (1), 26 (2), 27 (2), 28 (3), 29 (2) and 30 (5) May 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 – 186	100	Identified^(c)	System unstable (e.g., low efficiency, unstable column temperature)
NO_x	0 – 1129	200	Identified^(d)	System unstable (e.g., low efficiency, unstable column temperature)
SO₂	0 – 417	50	Identified^(e)	De-sulphurisation system tripped / Under Maintenance
VOCs (including methane) ^(b)	0 – 20	20	Nil	Nil
NH₃	0 – 797	35	Identified^(f)	System unstable (e.g., low efficiency, unstable column temperature)
HCl	0 – 27	10	Identified^(g)	System unstable (e.g., low efficiency, unstable column temperature)
HF	0 – 2	1	Identified^(h)	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) Dates with exceedances on CO (number of exceedances on the day) were identified on 29 (2) May 2023. (d) Dates with NO_x exceedances (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; 1 (13), 2 (3), 3 (5), 4 (8), 5 (3), 6 (11), 7 (17), 8 (14), 9 (9), 10 (8), 11 (12), 12 (13), 13 (6), 14 (15), 15 (11), 16 (2), 17 (1), 18 (9), 19 (2), 20 (4), 21 (2), 22 (2), 25 (2), 26 (1), 27 (2) and 28 (3) April 2023; 1 (4), 2 (7), 3 (9), 4 (20), 5 (18), 6 (24), 7 (23), 8 (6), 10 (5), 24 (1), 29 (3), 30 (4) and 31 (5) May 2023. (e) Dates with SO₂ exceedances (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; 2 (6), 3 (1), 7 (2), 8 (2), 15 (2), 17 (2), 18 (2) and 27 (1) April 2023; 3 (1), 29 (1), 30 (1) and 31 (2) May 2023. (f) Dates with NH₃ exceedances (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; 1 (12), 2 (9), 3 (17), 4 (1), 5 (3), 6 (16), 7 (19), 8 (15), 9 (17), 10 (18), 11 (17), 12 (13), 13 (5), 14 (1), 15 (10), 16 (16), 17 (22), 18 (22), 19 (6), 20 (16), 21 (12), 22 (14), 23 (24), 24 (17), 25 (7), 26 (5), 28 (3) and 29 (3) April 2023; 1 (1), 4 (1), 5 (1), 8 (9), 9 (24), 10 (16), 11 (23), 12 (19), 13 (18), 14 (22), 15 (9), 16 (22), 17 (14), 18 (18), 19 (14), 20 (22), 21 (1), 22 (8), 23 (16), 24 (14), 25 (9), 26 (9), 27 (1), 29 (6) and 30 (3) May 2023. (g) Date with exceedances on HCl (number of exceedances on the day) was identified on 24 (1) March 2023 (h) Date with exceedances on HF (number of exceedances on the day) was identified on 19 (1) May 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 ^(d)
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 and 3 May 2023. The standby flare did not operate in April. (d) Date with HF exceedances (number of exceedances on the day) were identified on 28 (1) March 2023.

4.2 Odour

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 monthly from the outlet chamber of the Effluent Storage Tank as stipulated in the operation phase discharge licence. Discharge from the Petrol Interceptors were sampled bi-monthly since July 2021 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 to 4.8. The results of the discharge samples from the Petrol Interceptors are recorded in Table 4.9 to 4.12.

Table 4.7 Results of the Discharge Sample Collected from the Outlet Chamber of the Effluent Storage Tank in March 2023

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 with Section B2 of the Effluent Discharge Licence under the WPCO. (b) Parameters required to be reported in accordance with 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 in the reporting month. (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 Collected from the Outlet Chamber of the Effluent Storage Tank in April 2023

Parameters	Discharged Effluent Concentration (mg/L)	Discharge Limit (mg/L)	Compliance with Discharge Limit
Flow Rate (m³/day)^(a)	14 – 201^(e)	645	Yes
pH (pH units)^(b)	7.41 – 9.00^(e)	6-10^(c)	Yes
Suspended Solids ^{(b) (d)}	77 ^(d)	800	Yes
Biochemical Oxygen Demand (5 days, 20°) ^{(b) (d)}	18 ^(d)	800	Yes
Chemical Oxygen Demand ^{(b) (}^d)	668 ^(d)	2,000	Yes
Oil & Grease ^{(b) (d)}	<5 ^(d)	40	Yes
Total Nitrogen ^{(b) (d)}	486 ^(d)	200	No^(f)
Total Phosphorus ^{(b) (d)}	25.5 ^(d)	50	Yes
Surfactants (total)^{(b) (d)}	<1.0 ^(d)	25	Yes
Notes: (a) Parameter not required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (b) Parameters required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (c) Daily Range. (d) Effluent sample collected on 13 April 2023. (e) Data collected daily in the reporting month. (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 13 April 2023.

Table 4.9 Results of the Discharge Sample Collected from the Outlet Chamber of the Effluent Storage Tank in May 2023

Parameters	Discharged Effluent Concentration (mg/L)	Discharge Limit (mg/L)	Compliance with Discharge Limit
Flow Rate (m³/day)^(a)	0 - 161^(e)	645	Yes
pH (pH units)^(b)	7.32 – 8.6^(e)	6-10^(c)	Yes
Suspended Solids ^{(b) (d)}	293 ^(d)	800	Yes
Biochemical Oxygen Demand (5 days, 20°) ^{(b) (d)}	70 ^(d)	800	Yes
Chemical Oxygen Demand ^{(b) (}^d)	1,430 ^(d)	2,000	Yes
Oil & Grease ^{(b) (d)}	<5 ^(d)	40	Yes
Total Nitrogen ^{(b) (d)}	218 ^(d)	200	No
Total Phosphorus ^{(b) (d)}	35.8 ^(d)	50	Yes
Surfactants (total)^{(b) (d)}	<1.0 ^(d)	25	Yes
Notes: (a) Parameter not required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (b) Parameters required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (c) Daily Range. (d) Effluent sample collected on 5 May 2023. (e) Data collected daily in the reporting month.

Table 4.10 Results of the Discharge Sample from the Petrol Interceptor 1 on 20 April 2023

Parameters	Discharged Effluent Concentration (mg/L)	Discharge Limit (mg/L)	Compliance with Discharge Limit
Suspended Solids^(b)	35 ^(a)	30	No
Chemical Oxygen Demand ^(c)	70 ^(a)	80	Yes
Oil & Grease ^(c)	<5 ^(a)	20	Yes
Surfactants (total)^(b)	<1.0 ^(a)	15	Yes
Notes: (a) Effluent sample collected on 20 April 2023. (b) Parameter not required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (c) Parameters required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO.

Table 4.11 Results of the Discharge Sample from the Petrol Interceptor 2 on 20 April 2023

Parameters	Discharged Effluent Concentration (mg/L)	Discharge Limit (mg/L)	Compliance with Discharge Limit
Suspended Solids ^(b)	19 ^(a)	30	Yes
Chemical Oxygen Demand ^(c)	66 ^(a)	80	Yes
Oil & Grease ^(c)	<5 ^(a)	20	Yes
Surfactants (total)^(b)	<1.0 ^(a)	15	Yes
Notes: (a) Effluent sample collected on 20 April 2023. (b) Parameter not required to be reported in accordance with Section B2 of the Effluent Discharge Licence under the WPCO. (c) Parameters required to be reported in accordance with 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([3]). Reference has been made to the Monthly Summary Waste Flow Tables 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 period are summarised in Table 4.12.

Table 4.12 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) (e)}	Recycled ^(c)
March 2023	0 L ^(d)	682.0 tonnes	0 tonnes	3.11 tonnes ^(e)	0.088 tonnes
April 2023	0 L^(d)	578.25 tonnes	0.26 tonnes	2.42 tonnes ^(e)	0.027 tonnes
May 2023	0 L ^(d)	662.27 tonnes	0 tonnes	2.88 tonnes ^(e)	0.130 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 tonnes of metals, 0.26 tonnes of papers/ cardboard packing and 0 tonnes of plastics were sent to recyclers for recycling during the reporting period. (c) Among general refuse, 0.011 tonnes of metals, 0.080 tonnes of papers/ cardboard packing and 0.037 tonnes of plastics were sent to recyclers for recycling during the reporting period. (d) No chemical waste was disposed of at CWTC in from March to May 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 inspections of the operation phase of the Project covered the operation phase environmental site inspections. The inspections 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).

Follow-up actions resulting from the site inspections were generally taken as reported by the Contractor. The Contractor has implemented environmental mitigation measures recommended in the approved EIA Report and EM&A Manual.

March 2023

The monthly inspection of the operation phase of the Project on 29 March 2023 covered the operation phase environmental site audit. Joint site inspections were conducted by representatives of the Contractor, IEC and the MT on 29 March 2023 as required for the operation of the Project.

April 2023

The monthly inspection of the operation phase of the Project on 21 April 2023 covered the operation phase environmental site audit. Joint site inspections were conducted by representatives of the Contractor, IEC and the MT on 21 April 2023 as required for the operation of the Project.

May 2023

The monthly inspection of the operation phase of the Project on 23 May 2023 covered the operation phase environmental site audit. Joint site inspections were conducted by representatives of the Contractor, IEC and the MT on 23 May 2023 as required for the operation of the Project.

5.2 Landscape and Visual Audit

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 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.

March 2023

Monthly inspection of the landscape and visual mitigation measures for the operation phase of the Project was performed on 29 March 2023.

April 2023

Monthly inspection of the landscape and visual mitigation measures for the operation phase of the Project was performed on 21 April 2023.

May 2023

Monthly inspection of the landscape and visual mitigation measures for the operation phase of the Project was performed on 23 May 2023.

6 Environmental Non-conformance

6.1 Summary of Environmental Non-Compliance

March 2023

Non-compliance of emission limits of VOCs (including methane) from CAPCS, NO_x and SO₂ from the CHPs, NO_x, 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 CHPs, the de-sulphurisation system, 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 exceedances are presented in Annex F.

April 2023

Non-compliance of emission limits of VOCs (including methane) from CAPCS, NO_x and SO₂ from CHP 1, Dust, NO_x, SO₂, HCl and HF from CHP 2; NO_x, SO₂ and NH₃ from ASP; 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 CHPs, the de-sulphurisation system and the ASP, 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 13 April 2023, leading to the high Total Nitrogen level.

The investigation reports of the above exceedances are presented in Annex F.

May 2023

Non-compliance of emission limits of Dust, VOCs, NO_x and SO₂ from CHP 1; Dust, NO_x and SO₂ from CHP 2; NO_x and SO₂ from CHP 3; CO, NO_x, SO₂, NH₃ and HF from ASP 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 investigated the cause of the exceedances and found that the exceedance of Total Nitrogen from the effluent discharge of the Effluent Storage Tank was potentially caused by the poor performance of the Sequential Batch Reactor (SBR), leading to an increased level of Total Nitrogen in the treated effluent sampled on 5 May 2023.

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 and the ASP, the potential causes for the exceedance were identified.

The investigation reports of the above exceedances are presented in Annex F.

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 Reporting Period

Activities to be undertaken for the coming reporting period are:

· Operation of the Project;

· CEMS maintenance;

· QAL 2 testing with 3^rd Party Lab was conducted for MCS 1 and MCS 2; and

· Completing the replacement of membrane diffusers for all of the SBR Tanks of the Wastewater Treatment Plant.

Conclusions

This EM&A Report presents the EM&A programme undertaken during the reporting period from 1 March to 31 May 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 stack monitoring (including CAPCS, CHP and ASP stacks) 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 Control 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; 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 and 30 April 2023.
Cogeneration Unit (CHP) 1	· Exceeded emission limit of Dust on 8 May 2023. · Exceeded emission limit of NO_x 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; 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 and 30 April; 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 30 and 31 May 2023. · Exceeded emission limit of SO₂ on 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 21, 29, 30 and 31 March; 1, 2, 9, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27 and 28 April; 1, 2, 3, 4, 5, 8, 11, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 30 and 31 May 2023. · Exceeded emission limit of VOC on 8 May 2023.
Cogeneration Unit (CHP) 2	· Exceeded emission limit of Dust on 17 and 18 April; 8 May 2023. · Exceeded emission limit of NO_x on 24, 25, 26, 27, 28, 29, 30 and 31 March; 1 – 30 April; 1 – 31 May 2023. · Exceeded emission limit of SO₂ on 24, 25, 26, 27, 28, 29, 30 and 31 March; 1 – 30 April; 1, 2, 4, 5, 6, 8, 9, 10, 12, 16, 18, 28, 29, 30 and 31 May 2023. · Exceeded emission limit of HCl on 17 and 18 April 2023. · Exceeded emission limit of HF on 17 April 2023.
Cogeneration Unit (CHP) 3	· Exceeded emission limit of NO_x 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; 21, 22, 23, 24, 25, 26, 27, 28, 29 and 30 May 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; 21, 22, 25, 26, 27, 28, 29 and 30 May 2023.
Ammonia Stripping Plant (ASP)	· Exceeded emission limit of CO on 29 May 2023. · Exceeded emission limit of NO_x 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; 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 25, 26, 27 and 28 April; 1, 2, 3, 4, 5, 6, 7, 8, 10, 24, 29, 30 and 31 May 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; 2, 3, 7, 8, 15, 17, 18 and 27 April; 3, 29, 30 and 31 May 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; 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, 28 and 29 April; 1, 4, 5, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 29 and 30 May 2023. · Exceeded emission limit of HF on 19 May 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, NO_x and SO₂ from the CHPs, HF from the Standby Flaring Gas Unit, and NO_x, SO₂, NH₃ and HCl from ASP were recorded in March 2023. The cause of the exceedances of VOCs (including methane) is due to faulty sensor. 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 NO_x of CHPs, NO_x, 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.

Non-compliance of emission limits of VOCs (including methane) from CAPCS, NO_x and SO₂ from CHP 1, Dust, NO_x, SO₂, HCl and HF from CHP 2 and NO_x, SO₂ and NH₃ from ASP were recorded in April 2023. The cause of the exceedances of VOCs (including methane) is due to faulty sensor. The exceedances of SO₂ from the CHPs occurred due to tripping of the de-sulphurisation system resulted from the residue of sulphur accumulated at the exhaust heat exchangers. The exceedances of dust, NO_x, HCl and HF from CHPs occurred due to system instability caused by prolonged usage of the CHPs. The exceedances of NO_x, SO₂and NH₃ from ASP occurred due to ASP pump failure which caused equipment trip.

Non-compliance of emission limits of Dust, VOCs, NO_x and SO₂ from CHP 1; Dust, NO_x and SO₂ from CHP 2; NO_x and SO₂ from CHP 3; and CO, NO_x, SO₂, NH₃ and HF from ASP were recorded in May 2023. The exceedances of SO₂ from the CHPs and ASP occurred due to tripping of the de-sulphurisation system. The exceedances of Dust, VOCs and NO_x from CHPs and the exceedances of CO, NO_x and HF from ASP occurred due to system instability.

Table 8.2 Exceedances for Petrol Interceptor 1 and 2

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, 13 April 2023, and 5 May 2023
Petrol Interceptor 1	· Exceeded discharge limit of Suspended Solid on 20 April 2023.

Non-compliance of discharge limit of Total Nitrogen from the Outlet Chamber of the Effluent Storage Tank were recorded on 9 March, 13 April and 5 May 2023. 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 and 13 April 2023. The contractor also found that poor performance of the Sequential Batch Reactor (SBR) leaded to an increased level of Nitrogen in the Treated Effluent sampled on 5 May 2023.

Non-compliance of discharge limit of Suspended Solids from Petrol Interceptor 1 was recorded during 20 April 2023. The Contractor suspected that the reason for the exceedances of the parameters was due to a lack of rainfall during the dry season, leading to an increase in the level of the exceeded parameters. The Contractor will further arrange a clean-up of the interceptors to make sure the discharge effluents comply with the discharge limit.

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 period.

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.

([1]) As some of the minor items are yet to be closed out in March 2019, the construction phase EM&A programme and Operation Phase EM&A programme were undertaking in parallel in March 2019.

([2]) A standby facility. Only operate when the CHPs are not in operation or when the biogas generated exceeded the utilisation rate of the CHPs.

([3]) Public fill and construction waste may only be generated during maintenance works when there are civil or structural works.

· Joint Environmental Site Inspections	3 times
· Landscape & Visual Inspections	3 times