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Contents

EXECUTIVE SUMMARY  i

Summary of works undertaken during the reporting month  i

Environmental monitoring and audit progress  i

findings of Environmental site audit  ii

Environmental exceedance/ non-conformance, complaint, summons and prosecution  ii

future key issues  ii

1.    Introduction  1

1.1   Purpose of the report  1

1.2   structure of the report  1

2.    project information  2

2.1   background  2

2.2   general site description  2

2.3   major activities undertaken  3

2.4   project organisation and management structure  3

2.5   status of environmental approval documents  3

3.    ENVIRONMENTAL MONITORING AND AUDIT REQUIREMENTS  4

3.1   Environmental monitoring  4

3.2   SITE AUDIT  8

4.    monitoring results  11

4.1   air quality  11

4.2   odour  14

4.3   water quality  14

4.4   waste management  16

5.    site audit  18

5.1   environmental site audit  18

5.2   landscape and audit  18

6.    environmental non-conformance and deficiencies  19

6.1   summary of environmental non-compliance and deficiencies  19

6.2   summary of environmental complaint  22

6.3   summary of environmental summon and successful prosecution  22

7.    future key issues  23

7.1   key issues for the coming month  23

8.    conclusions  24

Annex A      Project layout

Annex B      project organisation chart with contact details

Annex C      implementation schedule of mitigation measures

Annex D      waste flow table

Annex E      environmental complaint, environmental summons and prosecution log

Annex F      investigation report

 


 

List of Tables

Table 2.1     Summary of Activities Undertaken in the Reporting Period  3

Table 2.2     Summary of Environmental Licensing, Notification and Permit Status  3

Table 3.1     Sampling and Laboratory Analysis Methodology  4

Table 3.2     Emission Limit for CAPCS Stack  5

Table 3.3     Emission Limit for CHP Stack  5

Table 3.4     Emission Limit for ASP Stack  6

Table 3.5     Emission Limit for Standby Flaring Gas Unit () 6

Table 3.6     Odour Intensity Level  7

Table 3.7     Action and Limit Levels for Odour Nuisance  7

Table 3.8     Event and Action Plan for Odour Monitoring  7

Table 3.9     Discharge Limits for Effluent from the Outlet Chamber of the Effluent Storage Tank  9

Table 3.10    Discharge Limits for Effluent from the Petrol Interceptors  9

Table 4.1     Hourly Average of Parameters Recorded for CAPCS  11

Table 4.2     Hourly Average of Parameters Recorded for CHP 1  11

Table 4.3     Hourly Average of Parameters Recorded for CHP 2  12

Table 4.4     Hourly Average of Parameters Recorded for CHP 3  12

Table 4.5     Hourly Average of Parameters Recorded for ASP  13

Table 4.6     Hourly Average of Parameters Recorded for the Standby Flaring Gas Unit  13

Table 4.7     Results of the Discharge Sample from the Outlet Chamber of the Effluent Storage Tank (December 2024) 14

Table 4.8     Results of the Discharge Sample from the Outlet Chamber of the Effluent Storage Tank (January 2025) 15

Table 4.9     Results of the Discharge Sample from the Petrol Interceptor 2 (December 2024) 15

Table 4.10    Results of the Discharge Sample from the Petrol Interceptor 1  16

Table 4.11    Results of the Discharge Sample from the Petrol Interceptor 2  16

Table 4.12    Quantities of Waste Generated from the Operation of the Project  17

Table 6.1     Implementation of Measures/ Actions to Address any Exceedances  19

Table 8.1     Exceedances for Stack Emissions  24

 


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 117th Monthly Environmental Monitoring and Audit (EM&A) report presenting the EM&A works carried out during the period from 1 to 28 February 2025 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.

Environmental monitoring and audit progress

air Quality monitoring

Non-compliance of emission limits of Total Odour from CAPCS; NOx from CHP1; NOx from CHP2; NOx from CHP3; CO, NOx, SO2, NH3, and HCl from the ASP were recorded during the reporting period.

Water Quality

Discharge sample from the outlet chamber of the Effluent Storage tank was collected on 16 January 2025, but the laboratory report and result remained pending as at the date of the January 2025 EM&A report submission, and is now presented having received the laboratory report. All analytes were shown to be in compliance with discharge limits.

Discharge sample from the outlet chamber of the Effluent Storage tank was collected 13 February 2025 and all analytes were shown to be in compliance with discharge limits.

Samples from Petrol Interceptor 1 and 2 were collected on 19 February 2025 and 27 February 2025 respectively, but the laboratory reports and results remained pending as at the date of the February 2025 EM&A report submission, and will be presented in the subsequent report.  

Waste Management

Waste generated from the operation of the Project includes chemical waste, waste generated from pre-treatment process, and general refuse.

2,297 litre of chemical waste was disposed of at CWTC in February 2025. 

1,143.59 tonnes of waste generated from pre-treatment process from the operation of the Project were disposed of at landfill. Among the waste generated from pre-treatment process from the operation of the Project, 0.000 tonnes of metals, 0.000 tonnes of papers/cardboard packing and 0.000 tonnes of plastics were sent to recyclers for recycling during the reporting period.

Around 2.765 tonnes of general refuse from the operation of the Project were disposed of at landfill. Among the general refuse from the operation of the Project, 0.000 tonnes of metals, 0.032 tonnes of papers/cardboard packing and 0.007 tonnes 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 Monitoring Team (MT). The Independent Environmental Checker (IEC) was also present at the joint inspection on 21 February 2025.

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, complaint, summons and prosecution

Exceedances of the air emission limits for CHPs and ASP were recorded during the reporting period.

No complaint was received during the reporting period.

future key issues

Activities to be undertaken in the next reporting month include:

·         Implementation of various optimization measures in WWTP.


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 117th EM&A report which summarises the monitoring results and audit findings for the EM&A programme during the reporting period from 1 to 28 February 2025.

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 ([1]).

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 153.95 tonnes and treated an average of 113.11 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 CHPs, the ASP, and the biological wastewater treatment plant (153.95 t/d SSOW received).  

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 is 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 (CHPs) and the ammonia stripping plant (ASP) during the commissioning and operation phase. The most recent sensor calibration for the CAPCS system for VOCs and H2S were both carried out in January 2025. The most recent span calibrations for the CEMS systems (CHP1, CHP2, CHP3, and ASP) were carried out on 28 May 2024. Annual CAPCS calibration was carried out on 15 and 30 October 2024.

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

·      ASP

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 ([3]).

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 by Person-in-charge of Odour Monitoring:

Action by 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 weeks;

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 is to be sampled monthly from the outlet chamber of the Effluent Storage Tank, while effluent discharge is 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

Parameter

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 Interceptors

Parameter

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

(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 the relevant Water Quality results tables in Section 4 below.

(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. 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, CHPs, ASP, and the Standby Flaring Gas Unit during the reporting period are monitored on-line by the continuous environmental monitoring system (CEMS). The Standby Flaring Gas Unit did not operate during the reporting period.

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, CHPs, ASP and the Standby Flaring Gas Unit during the 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) (a)

0 – 1

680

Nil

Nil

Dust (or TSP)

0 – 0

6

Nil

Nil

Odour (including NH3 & H2S) (b)

0 – 261

220

Identified (c)

System unstable (e.g. low efficiency).

Notes:

(a)  The VOCs emission limit includes methane as biogas is adopted, as fuel in the combustion process.

(b)  The odour unit is ou/Nm3.

(c)   Date with Odour exceedances (number of exceedances on that day) was identified on 17(5) February 2025.

Table 4.2  Hourly Average of Parameters Recorded for CHP 1

Parameter

Range of Hourly Average Conc. (mg/Nm3) (a)

Emission Limit (mg/Nm3)

Exceedance Identified

Remarks

Dust (or TSP)

0 – 4

15

Nil

Nil

Carbon Monoxide

0 – 27

650

Nil

Nil

NOx

0 – 478

300

Identified (c)

System unstable (e.g. low efficiency)

SO2

0 – 16

50

Nil

Nil

VOCs (including methane) (b)

0 – 380

1,500

Nil

Nil

HCl

0 – 1

10

Nil

Nil

HF

0 – 0

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 NOx exceedances (number of exceedances on that day) were identified on 7(1), 14(3), 17(1), 25(13), 26(10) and 28(1) February 2025.

Table 4.3  Hourly Average of Parameters Recorded for CHP 2

Parameter

Range of Hourly Average Conc. (mg/Nm3) (a)

Emission Limit (mg/Nm3)

Exceedance Identified

Remarks

Dust (or TSP)

0 – 14

15

Nil

Nil

Carbon Monoxide

0 – 528

650

Nil

Nil

NOx

0 – 494

300

Identified (c)

System unstable (e.g. low efficiency)

SO2

0 – 13

50

Nil

Nil

VOCs (including methane) (b)

0 – 1145

1,500

Nil

Nil

HCl

0 – 9

10

Nil

Nil

HF

0 – 0

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 NOx exceedances (number of exceedances on that day) were identified on 8(3), 10(6), 11(11), 15(1), 20(10), 21(7) and 22(1) February 2025.


Table 4.4  Hourly Average of Parameters Recorded for CHP 3

Parameter

Range of Hourly Average Conc. (mg/Nm3) (a)

Emission Limit (mg/Nm3)

Exceedance Identified

Remarks

Dust (or TSP)

0 – 4

15

Nil

Nil

Carbon Monoxide

0 – 97

650

Nil

Nil

NOx

0 – 505

300

Identified (c)

System unstable (e.g. low efficiency)

SO2

0 – 6

50

Nil

Nil

VOCs (including methane) (b)

0 – 249

1,500

Nil

Nil

HCl

0 – 0

10

Nil

Nil

HF

0 – 0

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 NOx exceedances (number of exceedances on that day) were identified on 1(8), 4(4), 5(3), 8(1), 12(5), 13(11), 14(3), 16(2), 19(2), 20(4), 22(5), 23(9) and 24(3) February 2025.

Table 4.5  Hourly Average of Parameters Recorded for ASP

Parameter

Range of Hourly Average Conc. (mg/Nm3) (a)

Emission Limit (mg/Nm3)

Exceedance Identified

Remarks

Dust (or TSP)

0 – 4

5

Nil

Nil

Carbon Monoxide

0 – 207

100

Identified (c)

Incorrect sensor(s) reading

NOx

0 – 2773

200

Identified (d)

System unstable (e.g. low efficiency)

SO2

0 – 100

50

Identified (e)

System unstable (e.g. low efficiency)

VOCs (including methane) (b)

0 – 19

20

Nil

Nil

NH3

0 – 353

35

Identified (f)

System unstable (e.g. low efficiency)

HCl

0 – 15

10

Identified (g)

System unstable (e.g. low efficiency)

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 Carbon Monoxide exceedance (number of exceedances on that day) was identified on 28(1) February 2025.

(d)  Dates with NOx exceedances (number of exceedances on that day) were identified on 1(17), 2(21), 3(13), 4(16), 5(20), 6(24), 7(20), 8(24), 9(24), 10(24), 11(21), 12(24), 13(24), 14(18), 15(4), 16(11), 17(15), 18(19), 19(20), 20(5), 21(14), 22(21), 23(18), 24(20), 25(10), 26(8), 27(15) and 28(10) February 2025.

(e)  Dates with SO2 exceedances (number of exceedances on that day) were identified on 5(1), 21(1) 23(1), and 24(1) February 2025.

(f)   Dates with NH3 exceedances (number of exceedances on that day) were identified on 1(5), 2(2), 3(1), 4(3), 5(1), 15(1), 19(1), 21(6), 22(16), 23(11), 24(3), 25(1), 26(2), 27(5) and 28(4) February 2025.

(g)  Date with HCl exceedance (number of exceedances on that day) was identified on 24(1) February 2025.

Table 4.6  Hourly Average of Parameters Recorded for the Standby Flaring Gas Unit

Parameter

Range of Hourly Average Conc. (mg/Nm3) (a) (c)

Emission Limit (mg/Nm3)

Exceedance Identified

Remarks

Dust (or TSP)

5

Carbon Monoxide

100

NOx

200

SO2

50

VOCs (including methane) (b)

20

HCl

10

HF

1

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.

4.2       odour

4.2.1   OPERATION PHASE MONITORING

No monthly odour patrol was required to be conducted for this reporting period.

4.2.2   water quality

4.2.3   OPERATION PHASE MONITORING

Effluent discharge is 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 4.7 and the results from the Petrol Interceptor samples are recorded in Tables 4.84.9.

Discharge sample from the outlet chamber of the Effluent Storage tank was collected on 16 January 2025, but the laboratory report and result remained pending as at the date of the January 2025 EM&A report submission, and is now presented having received the laboratory report. Discharge sample from the outlet chamber of the Effluent Storage tank was collected 13 February 2025.

Sample from Petrol Interceptor 1 and 2 were collected on 19 February 2025 and 27 February 2025 respectively, but the laboratory reports and results remain pending as at the date of the February 2025 EM&A report submission, and will be presented in the subsequent report.

Table 4.7  Results of the Discharge Sample from the Outlet Chamber of the Effluent Storage Tank (January 2025)

Parameter

Discharged Effluent Concentration (mg/L)

Discharge Limit (mg/L)

Compliance with Discharge Limit

Flow Rate (m3/day) (a)

297 (e) (f)

645

Yes

pH (pH units) (b)

7.2 – 8.0 (e)

6 - 10 (c)

Yes

Suspended Solids (b) (d)

131 (d)

800

Yes

Biochemical Oxygen Demand (5 days, 20°) (b) (d)

35 (d)

800

Yes

Chemical Oxygen Demand (b) (d)

562 (d)

2,000

Yes

Oil & Grease (b) (d)

<5 (d)

40

Yes

Total Nitrogen (b) (d)

101 (d)

200

Yes

Total Phosphorus (b) (d)

13.4 (d)

50

Yes

Surfactants (total) (b) (d)

<1 (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)  Sample collected on 16 January 2025; data was pending as at the date of the January 2025 EM&A report and is now presented having received the laboratory report.

(e)  Data collected daily.

(f)   Maximum daily volume of wastewater discharged during the month.

 

Table 4.8  Results of the Discharge Sample from the Outlet Chamber of the Effluent Storage Tank (February 2025)

Parameter

Discharged Effluent Concentration (mg/L)

Discharge Limit (mg/L)

Compliance with Discharge Limit

Flow Rate (m3/day) (a)

250 (e) (f)

645

Yes

pH (pH units) (b)

8.0 - 8.8 (e)

6 - 10 (c)

Yes

Suspended Solids (b) (d)

197 (d)

800

Yes

Biochemical Oxygen Demand (5 days, 20°) (b) (d)

24 (d)

800

Yes

Chemical Oxygen Demand (b) (d)

701 (d)

2,000

Yes

Oil & Grease (b) (d)

<5 (d)

40

Yes

Total Nitrogen (b) (d)

69.6 (d)

200

Yes

Total Phosphorus (b) (d)

27.2 (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)  Sample collected on 13 February 2025.

(e)  Data collected daily.

(f)   Maximum daily volume of wastewater discharged during the month.

Table 4.9  Results of the Discharge Sample from the Petrol Interceptor 1

Parameter

Discharged Effluent Concentration (mg/L)

Discharge Limit (mg/L)

Compliance with Discharge Limit

Suspended Solids (b)

pending (a)

30

pending

Chemical Oxygen Demand (c)

pending  (a)

80

pending

Oil & Grease (c)

pending  (a)

20

pending

Surfactants (total) (b)

pending  (a)

15

pending

Notes:

(a)  Sample collected on 19 February 2025; data remain pending as at the date of the February 2025 EM&A report and will be presented in the subsequent monthly EM&A report once the lab results have been received.

(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 4.10 Results of the Discharge Sample from the Petrol Interceptor 2

Parameter

Discharged Effluent Concentration (mg/L)

Discharge Limit (mg/L)

Compliance with Discharge Limit

Suspended Solids (b)

pending  (a)

30

pending

Chemical Oxygen Demand (c)

pending  (a)

80

pending

Oil & Grease (c)

pending  (a)

20

pending

Surfactants (total) (b)

pending  (a)

15

pending

Notes:

(a)  Sample collected on 27 February 2025; data remain pending as at the date of the February 2025 EM&A report and will be presented in the subsequent monthly EM&A report once the lab results have been received.

(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.

4.3       waste management

4.3.1   OPERATION PHASE MONITORING

Wastes generated from the operation of the Project include chemical waste, wastes generated from pre-treatment process and general refuse ([4]). 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 4.11.

 

Table 4.11    Quantities of Waste Generated from the Operation of the Project

Month / Year

Chemical Waste

Waste Generated from
Pre-treatment Process

General Refuse

Disposed of at CWTC

Disposed of at Landfill (a)

Recycled (b)

Disposed of at Landfill (a)

Recycled (c)

February 2025

2,297 L 

1,143.59 tonnes

0.000 tonnes

2.765 tonnes (e)

0.039 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, 0.000 tonnes of metals, 0.000 tonnes of papers/cardboard packing and 0.000 tonnes of plastics were sent to recyclers for recycling during the reporting period.

(c)   Among general refuse, 0.000 tonnes of metals, 0.032 tonnes of papers/cardboard packing and 0.007 tonnes of plastics were sent to recyclers for recycling during the reporting period.

(d)  3400 kg of chemical waste was disposed of at CWTC during the reporting period, for unit consistency, it has been converted to litre based on 1.48 g/cm3 conversion factor.

(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 21 February 2025 covered the operation phase environmental site audit. Joint site inspection was conducted by representatives of the Contractor, IEC, and the MT 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:

21 February 2025

·         No particular observation during this inspection.

The Contractor has implemented the environmental mitigation measures recommended in the approved EIA Report and EM&A Manual.

5.2       landscape and audit

Inspection of the landscape and visual mitigation measures for the operation phase of the Project was performed on 21 February 2025.

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 21 February 2025. 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 Total Odour from CAPCS; NOx from CHP1; NOx from CHP2; NOx from CHP3; and CO, NOx, SO2, NH3, and HCl from the ASP 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, the CHPs, and the ASP; the potential causes for the exceedance were identified.

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

An overview of the various measures/ actions to be taken by the Contractor to address any exceedances is summarised in Table 6.1.

Table 6.1  Implementation of Measures/ Actions to Address any Exceedances

Monitoring Location

Measures/ Actions to Address any Exceedances

Implementation Timeline & Status

Centralised Air Pollution Unit (CAPCS)

·         To address the exceedances for Total Odour (ou/Nm3) recorded in January 2024 and February 2025, the Contractor ordered a new H2S / ORP sensor to replace the faulty one which was installed on 23 May 2024.

·         The cleaning of the ventilation pumps was conducted in April 2024.

·         The Contractor further identified that the ongoing exceedances for Dust, Total Odour, and VOCs from August 2024 – January 2025 were caused by chemical pipeline leakage, sensor issues, and the inefficiency of the chemical scrubber.

·         Fine-tuning measures and adjustment in the operation of the system were implemented in October 2024.

·         An enclosure has been set up to protect the VOC and H2S sensors, and an ozone deodorization unit has been installed as of November 2024. An air sample was also taken to compare the sensor data.

·         The Contractor has confined the leakage in the chemical pipeline and clean the chemical scrubber, currently waiting for repair works.

Cogeneration Unit 1 (CHP 1)

·         To address the ongoing NOx exceedances recorded from October 2023 – February 2025, the Contractor ordered 3 new cylinder heads from the supplier to replace the old ones and improve performance which were installed in May 2024.

·         To address the SO2 exceedances recorded from October 2023 – June 2024, August 2024, and November – December 2024, SO2 sampling and testing was completed by a third-party laboratory that showed lower SO2 values than those reported by the CEMS. The lower values measured by the laboratory was attributed to methane gas interference. Based on this study, it was proposed to implement a correction factor in the CEMS to adjust for the methane gas interference. After review by MT and IEC, the correction factor was implemented in May 2024.

·         The Contractor received additional training for operation of the CHPs during December 2024.

·         The fine-tuning measures were implemented during May 2024, and a further tuning was carried out on 12 August 2024.

·         To address the HCl exceedances recorded from October 2023 – April 2024, July 2024, September – October 2024, and January 2025, the Contractor implemented in May 2024 fine tuning measures such as reviewing the ignition temperature curve, spark plug condition check and adjusting the intake & exhaust valves on the cylinder to reduce the fluctuations in HCl emissions and keep within the permissible limit.

·         A CHP expert from Europe visited the ORRC1 facility in August 2024 to review the performance of the CHPs and recommended various spare parts be replaced.

·         The Contractor will receive additional advanced training from the manufacturer for the operation and maintenance of the equipment.

·         The Contractor identified that a buildup of silicon deposits on the cylinder heads of the CHPs is preventing the engines from reaching full loading and will require cleaning to resolve.

·         Contractor ordered spare parts for the CHPs which arrived in December 2024 and installation schedule is pending from the Contractor, currently waiting for the proper tools.

·         The Contractor will complete the cleaning of silicon deposits on the cylinder heads and the exhaust heat exchanger replacement works by Q1 2025.

Cogeneration Unit 2 (CHP 2)

·         To address the ongoing NOx exceedances recorded from October 2023 – October 2024 and January – February 2025, fine tuning of CHP 2 such as reviewing the ignition temperature curve, spark plug condition check and adjusting the intake & exhaust valves on the cylinder was conducted in May 2024 to reduce the fluctuations in NOx emissions and to keep within the permissible limit.

·         To address the SO2 exceedances recorded from October 2023 – April 2024, SO2 sampling and testing was completed by a third-party laboratory that showed lower SO2 values than those reported by the CEMS. The lower values measured by the laboratory was attributed to methane gas interference. Based on this study, it was proposed to implement a correction factor in the CEMS to adjust for the methane gas interference. After review by MT and IEC, the correction factor was implemented in May 2024.

·         To address the HCl exceedances recorded from November 2023 and April 2024, the Contractor implemented fine tuning measures such as reviewing the ignition temperature curve, spark plug condition check and adjusting the intake & exhaust valves on the cylinder to reduce the fluctuations in HCl emissions and keep within the permissible limit.

·         A CHP expert from Europe visited the ORRC1 facility in August 2024 to review the performance of the CHPs and recommended various spare parts be replaced.

·         A further tuning was carried out for the CHP on 12 August 2024.

·         The Contractor will receive additional advanced training from the manufacturer for the operation and maintenance of the equipment.

·         The Contractor identified that a buildup of silicon deposits on the cylinder heads of the CHPs is preventing the engines from reaching full loading and will require cleaning to resolve.

·         The Contractor received additional training for operation of the CHPs during December 2024.

·         Contractor ordered spare parts for the CHPs which arrived in December 2024 and installation schedule is pending from the Contractor, currently waiting for the proper tools.  

·         The Contractor will complete the cleaning of silicon deposits on the cylinder heads and the exhaust heat exchanger replacement works by Q1 2025.

Cogeneration Unit 3 (CHP 3)

·         To address the ongoing NOx exceedances from October 2023 – February 2025, fine tuning measures of CHP 3 were implemented in May 2024 such as reviewing the ignition temperature curve, spark plug condition check and adjusting the intake & exhaust valves on the cylinder to reduce the fluctuations in NOx emissions and to keep within the permissible limit.

·         To address the SO2 exceedances recorded from October 2023 – April 2024, SO2 sampling and testing was completed by a third-party laboratory that showed lower SO2 values than those reported by the CEMS. The lower values measured by the laboratory was attributed to methane gas interference. Based on this study, it was proposed to implement a correction factor in the CEMS to adjust for the methane gas interference. After review by MT and IEC, the correction factor was implemented in May 2024.

·         A further tuning was carried out on 12 August 2024.

·         A CHP expert from Europe visited the ORRC1 facility in August 2024 to review the performance of the CHPs and recommended various spare parts be replaced.

·         The Contractor will receive additional advanced training from the manufacturer for the operation and maintenance of the equipment.

·         The Contractor identified that a buildup of silicon deposits on the cylinder heads of the CHPs is preventing the engines from reaching full loading and will require cleaning to resolve.

·         The Contractor received additional training for operation of the CHPs during December 2024.

·         Contractor ordered spare parts for the CHPs which arrived in December 2024 and installation schedule is pending from the Contractor, currently waiting for the proper tools.

·         The Contractor will complete the cleaning of silicon deposits on the cylinder heads and the exhaust heat exchanger replacement works by Q1 2025.

Ammonia Stripping Plant (ASP)

·         To address the Carbon Monoxide exceedances recorded in February 2025, the Contractor arranged for a visit by the supplier to improve the reliability and performance of the system.

·         To address the ongoing NOx exceedances recorded from October 2023 – February 2025, the Contractor conducted an overhaul of the ASP and arranged for a visit by the supplier to improve the reliability and performance of the system. The overhaul was completed 6 May 2024.

·         To address the ongoing SO2 exceedances recorded from October 2023 – February 2025, SO2 sampling and testing was completed by a third-party laboratory that showed lower SO2 values than those reported by the CEMS. The lower values measured by the laboratory was attributed to methane gas interference. Based on this study, it was proposed to implement a correction factor in the CEMS to adjust for the methane gas interference. After review by MT and IEC, the correction factor was implemented in May 2024.

·         To address the ongoing NH3 exceedances recorded from October 2023 – February 2025, the Contractor conducted an overhaul of the ASP and arranged for a visit by the supplier.

·         To address the HCl exceedances recorded from October 2023 – May 2024 and August 2024 – November 2024, and February 2025, the Contractor conducted an overhaul of the ASP and arranged for a visit by the supplier.

·         The automatic situation of the TCU louvres has been resolved as of October 2024.

·         A visit from the supplier to inspect the ASP has been conducted.  

·         The Contractor in working on implementing further fine-tuning measures for the ASP since December 2024, the stability of ASP has been increased.

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:

·         Implementation of various optimization measures in WWTP.

 


8.         conclusions

This EM&A Report presents the EM&A programme undertaken during the reporting period from 1 to 28 February 2025 in accordance with the 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 CAPCS, CHPs, and the ASP 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

CAPCS

·         Exceeded emission limit of Total Odour on 17(5) February 2025. 

Cogeneration Unit 1 (CHP 1)

·         Exceeded emission limit of NOx on 7(1), 14(3), 17(1), 25(13), 26(10) and 28(1) February 2025.

Cogeneration Unit 2 (CHP 2)

·         Exceeded emission limit of NOx on 8(3), 10(6), 11(11), 15(1), 20(10), 21(7) and 22(1) February 2025.

Cogeneration Unit 3 (CHP 3)

·         Exceeded emission limit of NOx on 1(8), 4(4), 5(3), 8(1), 12(5), 13(11), 14(3), 16(2), 19(2), 20(4), 22(5), 23(9) and 24(3) February 2025.

Ammonia Stripping Plant (ASP)

·         Exceeded emission limit of Carbon Monoxide on 28(1) February 2025.

·         Exceeded emission limit of NOx on 1(17), 2(21), 3(13), 4(16), 5(20), 6(24), 7(20), 8(24), 9(24), 10(24), 11(21), 12(24), 13(24), 14(18), 15(4), 16(11), 17(15), 18(19), 19(20), 20(5), 21(14), 22(21), 23(18), 24(20), 25(10), 26(8), 27(15) and 28(10) February 2025.

·         Exceeded emission limit of SO2 on 5(1), 21(1) 23(1), and 24(1) February 2025.

·         Exceeded emission limit of NH3 on 1(5), 2(2), 3(1), 4(3), 5(1), 15(1), 19(1), 21(6), 22(16), 23(11), 24(3), 25(1), 26(2), 27(5) and 28(4) February 2025.

·         Exceeded emission limit of HCl on 24(1) February 2025.

Standby Gas Flaring Unit

·         The Standby Gas Flaring Unit did not operate in February 2025. 

 

Non-compliance of emission limits of Total Odour from CAPCS; NOx from CHP1; NOx from CHP2; NOx from CHP3; CO, NOx, SO2, NH3, and HCl from the ASP. The exceedances of Total Odour from CAPCS; NOx from the CHPs; as well as NOx, SO2, NH3, and HCl from the ASP occurred due to system instability. The exceedances of CO from the ASP occurred due to incorrect sensor(s) reading.

No complaint was received during the reporting period.

Discharge sample from the outlet chamber of the Effluent Storage tank was collected on 16 January 2025, but the laboratory report and result remained pending as at the date of the January 2025 EM&A report submission, and all analytes were shown to be in compliance with discharge limits. Discharge sample from the outlet chamber of the Effluent Storage tank was collected 13 February 2025 and all analytes were shown to be in compliance with discharge limits.  

Sample from Petrol Interceptor 1 and 2 were collected on 19 February 2025 and 27 February 2025 respectively, but the laboratory reports and results remained pending as at the date of the February 2025 EM&A report submission, and will be presented in the subsequent report.

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, the CAPCS, CHPs, and the ASP; the potential causes for the exceedances were identified.

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.


 

 



([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 operates when the CHPs are not in operation or when the biogas generated exceeded the utilisation rate of the CHPs.

([3]) The odour patrol route was changed during this reporting period to include sampling points that are frequently visited by visitors and eliminate sampling points that are not visited by visitors.

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