Contents
Executive Summary
1.1 Purpose of the Report
1.2 Structure of the Report
2.1 Background
2.2 General Site Description
2.3 Major Activities Undertaken
2.4 Project Organisation and Management Structure
2.5 Status of Environmental Approval Documents
3 Environmental Monitoring and Audit Requirements
3.1 Environmental Monitoring
3.1.1 Air Quality
3.1.2 Odour
3.2 Site Audit
3.2.1 Water Quality
3.2.2 Landscape and Visual
4.1 Air Quality
4.1.1 Commissioning Phase Monitoring
4.1.2 Operation Phase Monitoring
4.2 Odour
4.2.1 Operation Phase Monitoring
4.3 Water Quality
4.3.1 Operation Phase Monitoring
4.4 Waste Management
4.4.1 Operation Phase Monitoring
5.1 Environmental Site Audit
5.1.1 Operation Phase
5.2 Landscape and Visual Audit
6 Environmental Non-conformance
6.1 Summary of Environmental Non-Compliance
6.2 Summary of Environmental Complaint
6.3 Summary of Environmental Summon and Successful Prosecution
7.1 Key Issues for the Coming Reporting Period
LIST OF TABLES
Table 2.1 Summary of Activities Undertaken in the Reporting Period
Table 2.2 Summary of Environmental Licensing, Notification and Permit Status
Table 3.1Sampling and Laboratory Analysis Methodology
Table 3.2Emission Limit for CAPCS Stack
Table 3.3Emission Limit for CHP Stack
Table 3.4Emission Limit for ASP Stack
Table 3.5Emission Limit for Standby Flaring Gas Unit ()
Table 3.6Odour Intensity Level
Table 3.7Action and Limit Levels for Odour Nuisance
Table 3.8Event and Action Plan for Odour Monitoring
Table 4.1 Hourly Average of Parameters Recorded for CAPCS
Table 4.2 Hourly Average of Parameters Recorded for CHP 1
Table 4.3 Hourly Average of Parameters Recorded for CHP 2
Table 4.4 Hourly Average of Parameters Recorded for CHP 3
Table 4.5Hourly Average of Parameters Recorded for ASP
Table 4.9 Results of the Discharge Sample from the Petrol Interceptor 1 on 15 October 2021
Table 4.10 Results of the Discharge Sample from the Petrol Interceptor 2 on 15 October 2021
Table 4.11 Quantities of Waste Generated from the Operation of the Project
LIST OF ANNEXES
Annex A |
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Annex B |
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Annex C |
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Annex D |
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Annex E |
Environmental complaint, Environmental Summons and Prosecution Log |
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Annex F |
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Annex G |
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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.
This is the 26th Quarterly EM&A report which summarises the monitoring results and audit findings for the EM&A programme during the reporting period from 1 September to 30 November 2021.
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
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.
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 and treated an average of 116 to 136 tonnes of source separated organic waste per day during the reporting month.
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 waste water treatment plant (about 116 - 136 t/d SSOW input); and · Process fine-tune – adjustment of the ASP operational parameters with new treatment media, CEMS/SCADA modification and improvement work following equipment failures and the alteration of different operation modes and measures to adapt to the high variation of SSOW nature and sources. |
The project organisation chart and contact details are shown in Annex B.
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 |
WT00024352-2016 |
3 June 2016 – 30 June 2021 |
Approved on 3 June 2016 |
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 |
- |
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.
According to the EM&A Manual and EP requirements, stack monitoring are required during the commissioning and operation phase of the Project.
On-line monitoring (using continuous environmental monitoring system (CEMS) shall be carried out for the centralised air pollution unit (CAPCS), cogeneration units (CHP) and the ammonia stripping plant (ASP) during the commissioning and operation phase. The last calibration was carried out on 15 June 2021.
The monitoring data is transmitted instantaneously to EPD (Regional Office) by telemetry system.
When the on-line monitoring for certain parameter cannot be undertaken, monitoring will be carried out using the following methodology approved by the EPD.
Table 3.1 Sampling and Laboratory Analysis Methodology
Parameters |
Method |
Stacks to be Monitored |
Gaseous and vaporous organic substances (including methane) |
USEPA Method 18 |
· CAPCS · CHP · ASP |
Particulate |
USEPA Method 5 |
· CAPCS · CHP · ASP |
Carbon monoxide (CO) |
USEPA Method 10 |
· CHP · ASP |
Nitrogen oxides (NOx) |
USEPA Method 7E |
· CHP · ASP |
Sulphur dioxide (SO2); |
USEPA Method 6 |
· CHP · ASP |
Hydrogen chloride (HCl) |
USEPA Method 26A |
· CHP · ASP |
Hydrogen fluoride (HF) |
USEPA Method 26A |
· CHP · ASP |
Oxygen (O2); |
USEPA Method 3A |
· CAPCS · CHP · ASP |
Velocity and Volumetric Flow |
USEPA Method 2 |
· CAPCS · CHP · ASP |
Ammonia (NH3) |
USEPA CTM 027 |
· ASP |
Odour (including NH3 and H2S) |
EN 13725 |
· CAPCS |
Water vapour content (continuous measurement of the water vapour content should not be required if the sample exhaust gas is dried before the emissions are analysed) |
USEPA Method 4 |
· CAPCS · CHP · ASP |
Temperature |
USEPA Method 4 |
· CAPCS · CHP · ASP |
With reference to the EM&A Manual, the air emission of the stacks shall meet the following emission limits as presented in Tables 3.2 to 3.5.
Table 3.2 Emission Limit for CAPCS Stack
Parameter |
Emission Level (mg/Nm3) (a) |
VOCs (including methane) |
680 |
Dust (or Total Suspended Particulates (TSP)) |
6 |
Odour (including NH3 & H2S) |
220 (b) |
Notes: (a) Hourly average concentration (b) The odour unit is OU/Nm3 |
Table 3.3 Emission Limit for CHP Stack
Parameter |
Maximum Emission Level (mg/Nm3) (a) (b) |
Dust (or Total Suspended Particulates) |
15 |
Carbon Monoxide |
650 |
NOx |
300 |
SO2 |
50 |
NMVOCs (c) |
150 |
VOCs (including methane) (d) |
1,500 |
HCl |
10 |
HF |
1 |
Notes: (a) All values refer to an oxygen content in the exhaust gas of 6% and dry basis. (b) Hourly average concentration (c) NMVOCs should be monitored by gas sampling and laboratory analysis at an agreed interval. For the first 12 months (starting from August 2019), monitoring should be carried out at quarterly intervals. The monitoring frequency should then be reduced to half-yearly for next 12 months (starting from August 2020). (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. |
To determine the effectiveness of the proposed odour mitigation measures and to ensure that the operation of the ORRC1 will not cause adverse odour impacts, odour monitoring of the CAPCS stack (see Section 3.1.1) and odour patrol will be carried out.
Odour patrol shall be conducted by independent trained personnel/ competent persons in summer months (i.e. from July to September) for the first two operational years of ORRC1 at monthly intervals along an odour patrol route at the Project Site boundary as shown in Annex A.
The perceived odour intensity is divided into 5 levels. Table 3.6 describes the odour intensity for different levels.
Table 3.6 Odour Intensity Level
Level |
Odour Intensity |
0 |
Not detected. No odour perceived or an odour so weak that it cannot be easily characterised or described |
1 |
Slight identifiable odour, and slight chance to have odour nuisance |
2 |
Moderate identifiable odour, and moderate chance to have odour nuisance |
3 |
Strong identifiable, likely to have odour nuisance |
4 |
Extreme severe odour, and unacceptable odour level |
Table 3.7 shows the action level and limit level to be used for odour patrol. Should any exceedance of the action and limit levels occurs, actions in accordance with the event and action plan in Table 3.8 should be carried out.
Table 3.7 Action and Limit Levels for Odour Nuisance
Parameter |
Action Level |
Limit Level |
Odour Nuisance (from odour patrol) |
When one documented compliant is received (a), or Odour Intensity of 2 is measured from odour patrol. |
Two or more documented complaints are received (a) within a week; or Odour intensity of 3 or above is measured from odour patrol. |
Note: (a) Once the complaint is received by the Project Proponent (EPD), the Project Proponent would investigate and verify the complaint whether it is related to the potential odour emission from the ORRC1 and its on-site wastewater treatment unit. |
Table 3.8 Event and Action Plan for Odour Monitoring
Event |
Action |
|
|
Person-in-charge of Odour Monitoring |
Project Proponent (a) |
Action Level |
|
|
Exceedance of action level (Odour Patrol) |
1. Identify source/reason of exceedance; 2. Repeat odour patrol to confirm finding. |
1. Carry out investigation to identify the source/reason of exceedance. Investigation should be completed within 2 weeks; 2. Rectify any unacceptable practice; 3. Implement more mitigation measures if necessary; 4. Inform Drainage Services Department (DSD) or the operator of the Siu Ho Wan Sewage Treatment Works (SHWSTW) if exceedance is considered to be caused by the operation of the SHWSTW. 5. Inform North Lantau Refuse Transfer Station (NLTS) operator if exceedance is considered to be caused by the operation of NLTS. |
Exceedance of action level (Odour Complaints) |
1. Identify source/reason of exceedance; 2. Carry out odour patrol to determinate odour intensity. |
1. Carry out investigation and verify the complaint whether it is related to potential odour emission from the nearby SHWSTW; 2. Carry out investigation to identify the source/reason of exceedance. Investigation should be completed within 2 weeks; 3. Rectify any unacceptable practice; 4. Implement more mitigation measures if necessary; 5. Inform DSD or the operator of the SHWSTW if exceedance is considered to be caused by the operation of the SHWSTW. 6. Inform NLTS operator if exceedance is considered to be caused by the operation of NLTS. |
Limit Level |
|
|
Exceedance of limit level |
1. Identify source/reason of exceedance; 2. Inform EPD; 3. Repeat odour patrol to confirm findings; 4. Increase odour patrol frequency to bi-weekly; 5. Assess effectiveness of remedial action and keep EPD informed of the results; 6. If exceedance stops, cease additional odour patrol. |
1. Carry out investigation to identify the source/reason of exceedance. Investigation should be completed within 2 week; 2. Rectify any unacceptable practice; 3. Formulate remedial actions; 4. Ensure remedial actions properly implemented; 5. If exceedance continues, consider what more/enhanced mitigation measures should be implemented; 6. Inform DSD or the operator of the SHWSTW if exceedance is considered to be caused by the operation of the SHWSTW. |
Note: (a) Project Proponent shall identify an implementation agent. |
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.
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 to Section B2 of the Effluent Discharge Licence under the WPCO. (b) Parameters required to be monitored and reported by the Contractor in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (c) Range. |
Table 3.10 Discharge Limits for Effluent from the Petrol Interceptor(s) (as stipulated in WT00038391-2021)
Parameters |
Discharge Limit (mg/L) |
Flow Rate (m3/day) |
245 (a) |
Suspended Solids (b) |
30 |
Chemical Oxygen Demand (c) |
80 |
Oil & Grease (c) |
20 |
Surfactants (total) (b) |
15 |
Notes: (a) The surface runoff flow rate limit was estimated by the overall yearly rainfall data. As the actual flowrate from the petrol interceptors depends on the weather condition instead of the performance of the petrol interceptor, monitoring and reporting of this parameter is not required. Hence this parameter is not reported in Error! Reference source not found. and Table 4.10. (b) Parameter not required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (c) Parameters required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. |
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.
Monitoring results of air quality parameters from stack emissions of the centralised air pollution control system, the ammonia stripping plant and the cogeneration units will be provided once available to show compliance with the monitoring requirements stated in the EM&A Manual (Rev. F) to support the termination of the construction phase EM&A programme.
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, there is no need to operate the standby flare and therefore no monitoring of the flare stack was undertaken.
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, unstable operation, test runs and interference of sensor, are disregarded.
Table 4.1 Hourly Average of Parameters Recorded for CAPCS
Parameter |
Range of Hourly Average Conc. (mg/Nm3) |
Emission Limit (mg/Nm3) |
Exceedance Identified |
Remarks |
VOCs (including methane) |
0.00 – 131.03
|
680 |
Nil |
Nil |
Dust (or TSP) |
0.00 – 0.00 |
6 |
Nil |
Nil |
Odour (including NH3 & H2S) (b) |
0.00 – 218.87 |
220 |
Nil |
Nil |
Note: (a) The odour unit is OU/Nm3. |
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) |
NA (b) |
15 |
Nil |
Nil |
Carbon Monoxide |
NA (b) |
650 |
Nil |
Nil |
NOx |
NA (b) |
300 |
Nil |
Nil |
SO2 |
NA (b) |
50 |
Nil |
Nil |
VOCs (including methane) (c) |
NA (b) |
1,500 |
Nil |
Nil |
HCl |
NA (b) |
10 |
Identified |
Nil |
HF |
NA (b) |
1 |
Nil |
Nil |
Notes: (a) All values refer to an oxygen content in the exhaust gas of 6% and dry basis. (b) CHP 1 was shut down in this reporting period for maintenance and preparation of overhaul. (c) The VOCs emission limit include methane as biogas is adopted as fuel in the combustion process. |
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 – |
15 |
Nil |
Nil |
Carbon Monoxide |
0 – 359 |
650 |
Nil |
Nil |
NOx |
0 – 308 |
300 |
Identified (c) |
System unstable (e.g. low efficiency, unstable column temperature ) |
SO2 |
0 – 97 |
50 |
Identified (d) |
Desulpurisation system tripped and resumed to normal after urgent maintenance. |
VOCs (including methane) (b) |
0 – 1,084 |
1,500 |
Nil |
Nil |
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 include methane as biogas is adopted as fuel in the combustion process. (c) Date with exceedances on NOx (number of exceedances on the day) was identified on 1 (1), 2 (4) and 15 (1) September 2021. (d) Date with exceedances on SO2 (number of exceedances on the day) was identified on 1 (8), 2 (1), 8 (1), 9 (2), 11 (5), 12 (7) and 13 (6) September 2021. |
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 – 11 |
15 |
Nil |
Nil |
Carbon Monoxide |
0 – 578 |
650 |
Nil |
Nil |
NOx |
0 – 314 |
300 |
Identified (c) |
System unstable (e.g. low efficiency, unstable column temperature ) |
SO2 |
0 – 93 |
50 |
Identified (d) |
Desulpurisation system tripped and resumed to normal after urgent maintenance. |
VOCs (including methane) (b) |
0 – 1,363 |
1,500 |
Nil |
Nil |
HCl |
0 – 3 |
10 |
Nil |
Nil |
HF |
0 – 2 |
1 |
Nil |
Nil |
Notes: (a) All values refer to an oxygen content in the exhaust gas of 6% and dry basis. (b) The VOCs emission limit include methane as biogas is adopted as fuel in the combustion process. (c) Dates with exceedances on NOx (number of exceedances on the day) were identified on 4 (1), 9 (2) and 10 (4) September 2021. (d) Date with exceedances on SO2 (number of exceedances on the day) were identified on 1 (8), 9 (8), 11 (7), 12 (7) and 13 (6) September 2021. |
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 – 4 |
5 |
Nil |
Nil |
Carbon Monoxide |
0 – 95 |
100 |
Nil |
Nil |
NOx |
0 – 428 |
200 |
Identified (c) |
System unstable (e.g. low efficiency, unstable column temperature ) |
SO2 |
0 – 58 |
50 |
Identified (d) |
Desulpurisation system tripped and resumed to normal after urgent maintenance. |
VOCs (including methane) (b) |
0 – 166 |
20 |
Identified (e) |
System unstable (e.g. low efficiency, unstable column temperature ) |
NH3 |
0 – 670 |
35 |
Identified (f) |
System unstable (e.g. low efficiency, unstable column temperature ) |
HCl |
0 – 0 |
10 |
Nil |
Nil |
HF |
0 – 1 |
1 |
Nil |
Nil |
Notes: (a) All values refer to an oxygen content in the exhaust gas of 11% and dry basis. (b) The VOCs emission limit include methane as biogas is adopted as fuel in the combustion process. (c) Dates with exceedances on NOx (number of exceedances on the day) were identified on 4 (2), 9 (1), 10 (1), 13 (1), 15 (1), 16 (2), 22 (1), 24 (2) and 29 (2) September; 7 (1), 8 (10), 9 (17), 10 (3), 13 (3), 15 (3), 19 (2), 23 (1), 25 (2), 27 (2), 28 (2) and 29 (2) October; 3 (12), 4 (1), 5 (4), 9 (1), 10 (1), 13 (1), 15 (3), 17 (3), 18 (1), 26 (1), 27 (1), 29 (1) and 30 (5) November 2021. (d) Dates with exceedances on SO2 (number of exceedances on the day) were identified on 9 (3) and 11 (1) September 2021. (e) Dates with exceedances on VOCs (number of exceedances on the day) were identified on 13 (5) and 20 (1) October; 11 (1) and 16 (1) November 2021. (f) Dates with exceedances on NH3 (number of exceedances on the day) were identified on 4 (9), 18 (2), 20 (8), 21 (12), 22 (10), 24 (1), 25 (9), 26 (5) and 30 (1) September; 2 (6), 3 (2), 4 (8), 5 (3), 6 (7), 7 (2), 12 (2), 13 (15), 14 (6), 15 (5), 16 (7), 17 (8), 18 (2), 20 (2), 22 (5), 23 (9), 24 (3), 28 (2), 29 (4) and 31 (1) October; 1 (3), 6 (3), 7 (3), 8 (2), 9 (2), 10 (13), 11 (7), 12 (14), 13 (4), 15 (3), 16 (7), 17 (16), 18 (12), 20 (1), 21 (1), 22 (1), 27 (1) and 30 (1) November 2021. |
Odour patrol was conducted by the independent odour patrol team of ALS Technichem (HK) Pty Ltd on 3 September 2021. According to the EM&A Manual and EP requirements, it is considered an exceedance if the odour intensity recorded by the panellists is Level 2 or above. During this reporting period, no Level 2 Odour Intensity was recorded. The odour patrol result is shown in Annex G.
Effluent discharge was sampled monthly from 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 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 and 4.10.
Table 4.6 Results of the Discharge Sample Collected from the Effluent Storage Tank on 28 September 2021
Parameters |
Discharged Effluent Concentration (mg/L) |
Discharge Limit (mg/L) |
Compliance with Discharge Limit |
Flow Rate (m3/day) (a) |
0 - 266 (e) |
645 |
Yes |
pH (pH units) (b) |
7.40 – 8.46 (e) |
6-10 (c) |
Yes |
Suspended Solids (b) (d) |
254 (d) |
800 |
Yes |
Biochemical Oxygen Demand (5 days, 20°) (b) (d) |
50 (d) |
800 |
Yes |
Chemical Oxygen Demand (b) (d) |
1,530 (d) |
2,000 |
Yes |
Oil & Grease (b) (d) |
<5 (d) |
40 |
Yes |
Total Nitrogen (b) (d) |
135 (d) |
200 |
Yes |
Total Phosphorus (b) (d) |
26.8 (d) |
50 |
Yes |
Surfactants (total) (b) (d) |
1.8 (d) |
25 |
Yes |
Notes: (a) Parameter not required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (b) Parameters required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (c) Daily Range. (d) Effluent sample collected on 28 September 2021. (e) Data collected daily. |
Table 4.7 Results of the Discharge Sample Collected from the Effluent Storage Tank on 15 October 2021
Parameters |
Discharged Effluent Concentration (mg/L) |
Discharge Limit (mg/L) |
Compliance with Discharge Limit |
Flow Rate (m3/day) (a) |
39 - 460 (e) |
645 |
Yes |
pH (pH units) (b) |
7.97 – 8.31 (e) |
6-10 (c) |
Yes |
Suspended Solids (b) (d) |
540 (d) |
800 |
Yes |
Biochemical Oxygen Demand (5 days, 20°) (b) (d) |
68 (d) |
800 |
Yes |
Chemical Oxygen Demand (b) (d) |
1,830 (d) |
2,000 |
Yes |
Oil & Grease (b) (d) |
<5 (d) |
40 |
Yes |
Total Nitrogen (b) (d) |
197 (d) |
200 |
Yes |
Total Phosphorus (b) (d) |
29.7 (d) |
50 |
Yes |
Surfactants (total) (b) (d) |
3.1 (d) |
25 |
Yes |
Notes: (f) Parameter not required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (g) Parameters required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (h) Daily Range. (i) Effluent sample collected on 15 October 2021. (j) Data collected daily. |
Table 4.8 Results of the Discharge Sample Collected from the Effluent Storage Tank on 9 November 2021
Parameters |
Discharged Effluent Concentration (mg/L) |
Discharge Limit (mg/L) |
Compliance with Discharge Limit |
Flow Rate (m3/day) (a) |
0 - 241 (e) |
645 |
Yes |
pH (pH units) (b) |
7.97 – 8.13 (e) |
6-10 (c) |
Yes |
Suspended Solids (b) (d) |
158 (d) |
800 |
Yes |
Biochemical Oxygen Demand (5 days, 20°) (b) (d) |
30 (d) |
800 |
Yes |
Chemical Oxygen Demand (b) (d) |
934 (d) |
2,000 |
Yes |
Oil & Grease (b) (d) |
<5 (d) |
40 |
Yes |
Total Nitrogen (b) (d) |
49.9 (d) |
200 |
Yes |
Total Phosphorus (b) (d) |
24.3 (d) |
50 |
Yes |
Surfactants (total) (b) (d) |
<1.0 (d) |
25 |
Yes |
Notes: (k) Parameter not required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (l) Parameters required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (m) Daily Range. (n) Effluent sample collected on 9 November 2021. (o) Data collected daily. |
Table 4.9 Results of the Discharge Sample from the Petrol Interceptor 1 on 15 October 2021
Parameters |
Discharged Effluent Concentration (mg/L) |
Discharge Limit (mg/L) |
Compliance with Discharge Limit |
Suspended Solids (b) |
12 (a) |
30 |
Yes |
Chemical Oxygen Demand (c) |
56 (a) |
80 |
Yes |
Oil & Grease (c) |
<5 (a) |
20 |
Yes |
Surfactants (total) (b) |
<1.0 (a) |
15 |
Yes |
Notes: (a) Effluent sample collected on 15 October 2021. (b) Parameter not required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (c) Parameters required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. |
Table 4.10 Results of the Discharge Sample from the Petrol Interceptor 2 on 15 October 2021
Parameters |
Discharged Effluent Concentration (mg/L) |
Discharge Limit (mg/L) |
Compliance with Discharge Limit |
Suspended Solids (b) |
<2 (a) |
30 |
Yes |
Chemical Oxygen Demand (c) |
15 (a) |
80 |
Yes |
Oil & Grease (c) |
<5 (a) |
20 |
Yes |
Surfactants (total) (b) |
<1.0 (a) |
15 |
Yes |
Notes: (a) Effluent sample collected on 15 October 2021. (b) Parameter not required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. (c) Parameters required to be reported in accordance to Section B2 of the Effluent Discharge Licence under the WPCO. |
No exceedance of discharge limit was recorded during the reporting period.
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 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
|
General Refuse |
||
|
Disposal of at CWTC |
Disposed of at Landfill (a) |
Recycled (b) |
Disposed of at Landfill (a) (c) |
Recycled (d) |
September 2021 |
2,400 L (e) |
304.01 tonnes |
0.00 tonnes |
2.88 tonnes |
0.00 tonne |
October 2021 |
0 L |
342.38 tonnes |
0.00 tonnes |
2.65 tonnes |
0.00 tonne |
November 2021 |
2,000 L (f) |
394.26 tonnes |
0.00 tonnes |
3.00 tonnes |
0.00 tonne |
Notes: (a) Waste generated from pre-treatment process and general refuse other than chemical waste and recyclables were disposed of at NENT landfill by sub-contractors. (b) Among waste generated from pre-treatment process, 0.00 tonne of metals, 0.00 tonne of papers/ cardboard packing and 0.00 tonne of plastics were sent to recyclers for recycling during the reporting period. (c) 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. (d) Among general refuse, 0.00 tonnes of metals, 0.00 tonnes of papers/ cardboard packing and 0 tonnes of plastics were sent to recyclers for recycling during the reporting period. (e) It includes 1,000 L of spent ferric chloride solution and 1,400 L of spent lube oil. (f) 2,000 L of spent lube oil was disposed of at CWTC in November 2021. |
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.
September 2021
The monthly inspection of the operation phase of the Project on 17 September 2021 covered the operation phase environmental site audit. Joint site inspections was conducted by representatives of the Contractor, IEC and the MT on 17 September 2021 as required for the operation of the Project.
October 2021
The monthly inspection of the operation phase of the Project on 27 October 2021 covered the operation phase environmental site audit. Joint site inspections was conducted by representatives of the Contractor, IEC and the MT on 27 October 2021 as required for the operation of the Project.
November 2021
The monthly inspection of the operation phase of the Project on 26 November 2021 covered the operation phase environmental site audit. Joint site inspections was conducted by representatives of the Contractor, IEC and the MT on 26 November 2021 as required for the operation of the Project.
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.
September 2021
Monthly inspection of the landscape and visual mitigation measures for the operation phase of the Project was performed on 17 September 2021.
October 2021
Monthly inspection of the landscape and visual mitigation measures for the operation phase of the Project was performed on 27 October 2021.
November 2021
Monthly inspection of the landscape and visual mitigation measures for the operation phase of the Project was performed on 26 November 2021.
September 2021
Non-compliance of emission limits for CHP and 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 air pollution control systems for the CHP and ASP and identified several potential causes for the exceedance. Remedial and follow-up actions had been recommended to the Contractor to perform accordingly. The Investigation Report is shown in Annex F.
August 2021
Non-compliance of emission limits for CHP and 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 air pollution control systems for the CHP and ASP and identified several potential causes for the exceedance. Remedial and follow-up actions had been recommended to the Contractor to perform accordingly. The Investigation Report is shown in Annex F.
October 2021
Non-compliance of emission limits for CHP and 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 air pollution control systems for the CHP and the ASP and identified several potential causes for the exceedance. Remedial and follow-up actions had been recommended to the Contractor to perform accordingly. The Investigation Report is shown in Annex F.
Activities to be undertaken for the coming reporting period are:
· Operation of the Project.
· Modification of the CHP and ASP to control the air emission.
This EM&A Report presents the EM&A programme undertaken during the reporting period from 1 September to 30 November 2021 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) |
· Nil |
Cogeneration Unit (CHP) 1 |
· Nil (CHP 1 was shut down in this reporting period for maintenance and preparation of overhaul) |
Cogeneration Unit (CHP) 2 |
· Exceeded emission limit of NOx on 1, 2, and 15 September · Exceeded emission limit of SO2 on 1, 2, 8, 9, 11, 12 and 13 September 2021 |
Cogeneration Unit (CHP) 3 |
· Exceeded emission limit of NOx on 4, 9 and 10 September. · Exceeded emission limit of SO2 on 1, 9, 11, 12 and 13 September 2021 |
Ammonia Stripping Plant (ASP) |
· Exceeded emission limit of NOx on 4, 9, 10, 13, 15, 16, 22, 24 and 29 September; 7, 8, 9, 10, 13, 15, 19, 23, 25, 27, 28 and 29 October; 3, 4, 5, 9, 10, 13, 15, 17, 18, 26, 27, 29 and 30 November 2021. · Exceeded emission limit of SO2 on 9 and 11 September; 2021 · Exceeded emission limit of VOCs on 13 and 20 October; 11 and 16 November 2021 · Exceeded emission limit of NH3 on 4, 18, 20, 21, 22, 24, 25, 26 and 30 September; 2, 3, 4, 5, 6, 7, 12, 13, 14, 15, 16, 17, 18, 20, 22, 23, 24, 28, 29 and 31 October; 1, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 20, 21, 22, 27 and 30 November 2021 |
In September, the exceedances in NOx of CHP were found to be a result of the low biogas loading at the CHP. The exceedances of SO2 of CHPs and ASP were found to be a result of the tripping of the desulphurisation system. In October, The exceedances of NOx, VOCs and NH3 in ASP were found to be a result of the unstable condition of the ASP system. In November, the exceedances of NOx, VOCs and NH3 in ASP were found to be a result of the unstable condition of the ASP system caused by unstable water flow resulted from the malfunctioning of various equipment (including the hot water circulation pump), leakage of piping and the blockage of the steam generator.
The Contractor has replaced malfunctioned parts (desulphurisation system, columns of the ASP), cleaning for various parts (i.e. stripping column and packaging of the ASP), and carried out fine-tuning of equipment of the ASP, the investigation on the underlying reasons of exceedances in CHP and ASP and the continuous seeking of better and more feedstock to increase biogas loading and testing at ASP to optimise combustion efficiency and overall performance.
No non-compliance to the effluent discharge limit was recorded during this reporting period.
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.
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 26th quarterly Environmental Monitoring and Audit (EM&A) report presenting the EM&A works carried out during the period from 1 September to 30 November 2021 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; and
· Process fine-tune, including adjustment of the ASP with new treatment media, modification of Continuous Environmental Monitoring System (CEMS) and Supervisory Control and Data Acquisition System (SCADA) rectification and improvement works following equipment failures and the alteration of different operation modes and measures to adapt to the high variation of SSOW nature and sources.
Environmental Monitoring and Audit Progress
Air Quality Monitoring
Exceedances on NOx and SO2 from CHP and NOx, SO2, VOCs and NH3 from ASP were recorded on the on-line monitoring system from September to November 2021. 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.
In September, the exceedances in NOx of CHP were found to be a result of the low biogas loading at the CHP. The exceedances of SO2 of CHPs and ASP were found to be a result of the tripping of the desulphurisation system. In October, The exceedances of NOx, VOCs and NH3 in ASP were found to be a result of the unstable condition of the ASP system. In November, the exceedances of NOx, VOCs and NH3 in ASP were found to be a result of the unstable condition of the ASP system caused by unstable water flow resulted from the malfunctioning of various equipment (including the hot water circulation pump), leakage of piping and the blockage of the steam generator.
The Contractor has implemented mitigation measures to control the exceedance (including replacement of malfunctioned parts (desulphurisation system, columns of the ASP), cleaning for various parts (i.e. stripping column and packaging of the ASP), and carried out fine-tuning of equipment of the ASP).
The Contractor is recommended to closely monitor the processes of the modification of the ASP and the post-modification monitoring of emission level to avoid any exceedance.
As similar issues have been re-occurred for sometimes, the Contractor is advised to undertake a comprehensive review of the operation of the concerned systems and the effectiveness of the existing mitigation measures and proposed further measures to avoid the exceedance.
Odour patrol was conducted by the independent odour patrol team of ALS Technichem (HK) Pty Ltd on 3 September 2021. No Level 2 Odour Intensity was recorded during odour patrols.
No non-compliance to the effluent discharge limit stipulated in the discharge licence issued by the EPD under the Water Pollution Control Ordinance was recorded during this reporting period.
Waste generated from the operation of the Project includes chemical waste, waste generated from pre-treatment process and general refuse.
4,400 L of chemical waste was collected by licenced waste collector from the operation of the Project.
1,040.65 tonnes of waste generated from pre-treatment process from the operation of the Project was disposed of at landfill. Among the recyclable waste generated from pre-treatment process from the operation of the Project, 0.00 tonnes of metals, 0.00 tonnes of papers/ cardboard packing and 0.00 tonnes of plastics were sent to recyclers for recycling during the reporting period.
Around 8.53 tonnes of general refuse from the operation of the Project was disposed of at landfill. Among the recycled general refuse from the operation of the Project, 0.00 tonnes of metals, 0.00 tonnes of papers/ cardboard packing and 0.00 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 |
3 times |
· Landscape & Visual Inspections |
3 times |
Monthly joint environmental site inspections were carried out. The environmental control/ mitigation measures (related to air quality, water quality, waste (including land contamination prevention), hazard-to-life and landscape and visual) recommended in the approved EIA Report and the EM&A Manual were properly implemented by the Contractor during the reporting month.
Environmental Exceedance/Non-conformance/Compliant/Summons and Prosecution
Exceedances for the air emission limits for the CHP and ASP stacks were recorded during the reporting period.
No complaint/ summon/prosecution was received in this reporting period.
Future Key Issues
Activities to be undertaken in the next reporting month include:
· Operation of the Project.
· Modification of the CHP and ASP to control the air emission.
([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.