National_Energy_Board_Report Page444

No.

Conditions with initial ﬁlings due prior to commencing construction, or prior to

commencing construction of speciﬁed Project component(s)

CPCN

OC2

OC49

Temp

Pump1

Pump2

Tanks

Deact

Trans Mountain Expansion Project 2016

425

Secondary containment – Burnaby Terminal

Trans Mountain must ﬁle with the NEB for approval,

at least 6 months prior to

commencing construction

, the ﬁnal design of the Burnaby Terminal, including a

report demonstrating the following:

a) the drainage system’s capability to rapidly and safely channel a signiﬁcant

release from either Tank 96, 97, or 98 to the Partial Remote Impoundment at the

same time that a design precipitation event is occurring, without overtopping

the diked areas.

b) the adequacy of the proposed design in mitigating the following consequences

of an accidental release and/or ignition of hydrocarbons, both within and

beyond the Burnaby Terminal property boundary:

harm to personnel and the public;

ii) environmental damage; and

iii) damage to facilities; and

c) the ability of the individual secondary containment areas, Common

Impoundment areas, Intermediate Stormwater Retention, Partial Remote

Impoundment, and Tertiary Containment to contain a release of hydrocarbons

from a multiple-tank rupture scenario concurrent with a 1-in-100 year, 24-hour

storm event. The scenario must include an allowance for water generated from

potential ﬁreﬁghting activities and the maximum potential amount of standing

water in all areas of the secondary containment system. The assessment may

include a calculation of the probability of exceedance of on-site containment

considering all possible tank rupture combinations, excluding those tanks with

suﬃcient individual secondary containment. The calculation may be based

on a tank utilization histogram most representative of the expanded terminal

operations, similar to that provided in Attachment 1 of Trans Mountain’s

response to NEB Information Request No. 4.24a) (Filing A4K4X3).

Secondary containment – Sumas Terminal

Trans Mountain must ﬁle with the NEB for approval,

at least 6 months prior to

commencing construction

, the ﬁnal design of the Sumas Terminal, including a

report demonstrating the following:

a) the adequacy of the proposed design in preventing the following consequences

of an accidental release and/or ignition of hydrocarbons, both within and

beyond the Sumas Terminal property boundary:

harm to personnel and the public;

ii) environmental damage; and

iii) damage to facilities; and

b) the ability of the secondary containment system to contain a release of

hydrocarbons from a multiple-tank rupture scenario concurrent with a 1-in-100

year, 24-hour storm event. The scenario must include an allowance for water

generated from potential ﬁreﬁghting activities and the maximum potential

amount of standing water in all areas of the secondary containment system.

The assessment may include a calculation of the probability of exceedance

of on-site containment considering all possible tank rupture combinations,

excluding those tanks with suﬃcient individual secondary containment. The

calculation may be based on a tank utilization histogram most representative

of the expanded terminal operations, similar to that provided in Attachment 1

of Trans Mountain’s response to NEB Information Request No. 4.24b) (Filing

A4K4X4).