10.1.1
The proposed relocation works of DHSRs mainly comprise
construction of caverns and tunnel, construction of ancillary building,
structural works for relocated DHSRs, watermain laying, E&M installation
and other associated works.
10.1.2
This Section addresses the issues with regard to
the hazard to life assessment as specified in the EIA Study Brief
(ESB-317/2019).
10.2.1
The key legislation and guidelines that are
considered relevant to the development of the Project are as follows:
·
Dangerous Goods Ordinance, Chapter 295;
·
Environmental Impact Assessment Ordinance
(EIAO), Chapter 499;
·
Annex 4 of Technical Memorandum on Environmental
Impact Assessment Process (EIAO-TM); and
·
The EIA Study Brief (ESB-317/2019), Section
3.4.10 and Appendix I
10.2.2
According to the EIA Study Brief, if use of
explosives for rock blasting is required and the locations of magazine for
overnight storage of explosives are in close vicinity to populated areas,
hazard assessment shall be carried out as follows:
(i)
Identify hazardous scenarios associated with any
storage, use and transport of explosives and then determine a set of relevant
scenarios to be included in a Quantitative Risk Assessment (QRA);
(ii)
Execute a QRA of the set of hazardous scenarios
determined in (i), expressing population risks in
both individual and societal terms;
(iii) Compare
individual and societal risk with the criteria for evaluating hazard to life
stipulated in Annex 4 of the TM; and
(iv) Identify
and assess practicable and cost-effective risk mitigation measures.
10.3.1
During construction phase, explosives,
classified as Category 1 Dangerous Goods, will be used for the tunnel/caverns construction. Explosives will be delivered daily to
the Project site and loaded immediately for blasting. The estimated quantity is
about 35-100 kg/day subject to the actual construction site condition. The
Project will not involve any overnight storage of
explosives.
10.3.2
Diesel oil, classified as Category 5 (Class 3)
dangerous goods, will be stored inside storage tank within the ancillary
building for emergency electricity generation during operation phase. The
estimated storage quantity is about 1,500L, which is below the exempt quantity
limit of 2,500L under the Dangerous Goods (General) Regulations (Cap. 296B). Considering
the small amount of diesel oil storage and proper storage for emergency use, no
unacceptable associated off-site impacts are anticipated during operation
phase.
10.3.3
No manufacturing of dangerous goods during both
construction and operation phases of the Project.
10.3.4
The proposed relocated DHSRs is located on and
underneath a south-facing hillslope at Lion Rock, which is north to Ma Chai
Hang FWSR, and west to Shatin Pass Road. Caverns will be constructed to house
the relocated DHSRs and connected to the portal near the Lion Park Transit
Nursery Landscape Section with access tunnel. Drill and blast method will be
adopted for the majority of excavation works. Explosives will be used for the
rock blasting. Most of the excavation works will be carried out inside caverns
except the construction of tunnel portals. No works area will be located within
the consultation zone of any Potentially Hazardous Installation (PHI).
10.3.5
Potential hazards are related to the storage and
use of explosives for the construction of the tunnel and caverns. Based on the
proposed construction programme and the blasting
frequencies, there will be no requirement for overnight storage of explosives. The delivery of the explosives will be once per
day. The delivery of explosives from Government Explosives Depots to the
blasting site is arranged by the Mines Division. Explosives are classified as
Category 1 Dangerous Goods and use of explosives is controlled under the
Dangerous Goods Ordinance (Chapter 295). The Project will not involve any
overnight storage of explosives, no QRA is required for this study.
10.4.1
Considering no overnight storage of explosives
under this Project, environmental monitoring and audit is not required.
10.5.1
The Project will not involve any overnight
storage of explosives. Transportation of explosives to site for cavern and tunnel
construction will be undertaken on a daily basis. The contractor is required to
destroy any unused explosives before nightfall.
END OF TEXT