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Safety and environmental standards for fuel storage sites
Final report
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213 The process of risk assessment assesses the level of risk posed by the establishment
as a whole and to inform planning of measures such as tertiary containment and emergency
arrangements. The potential for bund failure from the effects of fire/explosion and failure to retain
liquid due to design and construction aspects needs to be recognised to assess the extent
to which tertiary containment may be required. The greater the deviation from good practice,
the more likely it is bunds will fail and the greater the rate of liquid release from the bund. The
paragraph c arrangement in Table 4 does not require upgrade for fire resistance.
214 Where it is difficult to install product-resistant sealants to ensure a liquid tight seal, for
example due to the condition of the concrete faces of the joint, it may be practicable to create a
new joint with fireproof waterstop on the outside of existing bund wall. This would require two new
concrete pillars joined to the outside of the bund wall either side of the existing bund wall joint.
A fireproof waterstop joint could be installed between the two new pillars which would then form
the new bund wall joint. Care would need to be taken to ensure pillars are supported with suitable
foundations and that any new stresses would not lead to cracking of the existing bund wall.
215 It is recommended that a suitable fire test method be agreed and a test programme of trial
joints be carried out to confirm the observed suitability of these expansion joint arrangements.
216 Figure 11 shows a design for the BSTG wall joint with stainless steel protective plate.
Fire resistant sealant and
flexible backing rod
Stainless steel plate
drilled with oversized
holes for stainless
steel bolts
Fire resistant sealant and
intumescent expansion
joint system and flexible
backing rod
OUTSIDE BUND
INSIDE BUND
Existing bund wall
Figure 11
BSTG wall joint with stainless steel
217 Figure 11 shows a bund wall joint with a stainless steel waterstop.