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CDOIF
Chemical and Downstream Oil
Industries Forum
CDOIF is a collaborative venture formed to agree strategic
areas for joint industry / trade union / regulator action aimed at
delivering health, safety and environmental improvements with
cross-sector benefits
Page 16
Supplement to Guideline – ‘Environmental Risk Tolerability for COMAH Establishments’
Storage Terminal Example v0.0
Receptor Type 15 – fresh and estuarine water habitats (adjacent estuary)
Frequency per establishment per receptor per year
MATTE
Consequence
Level
10
-8
– 10
-7
10
-7
– 10
-6
10
-6
– 10
-5
10
-5
– 10
-4
10
-4
– 10
-3
10
-3
– 10
-2
>10
-2
D – MATTE
Intolerable
C - MATTE
TifALARP
B - MATTE
Broadly Acceptable
Mi
UnMi
A - MATTE
Mi
UnMi
Sub MATTE
Tolerability not considered under the CDOIF environmental risk tolerability methodology
In a full Phase I assessment the unmitigated and mitigated risk tolerability would be defined for each
relevant environmental receptor.
3.4 Outcome of Phase I Screening
From these matrices, it can be seen that all of the unmitigated risks to all receptors are in the
‘intolerable’ range. When the protection provided by the preventative and mitigation controls are
accounted for, the mitigated risk to most receptors is reduced to within the TifALARP range.
However, one environmental receptor, the Godwit living in the estuary (receptor type 13 – particular
species), remains in the ‘intolerable’ range. This is primarily driven by the higher consequence level
(C) of a MATTE harming this receptor.
The outcome of this screening level assessment is that the Godwit residing in the estuary are one of
the most vulnerable receptors in the event of an acute release, primarily from scenarios H01
(release from a semi-buried tank), H02 (acute release of diesel during vessel unloading at the jetty)
and H04 (release of fire water containing foam and entrained hydrocarbons). The pathways by
which the Godwit population could be impacted are migration within the drainage network and
overland flow (scenarios H01 and H04) and by direct release into surface water (scenario H04).