API RP 581 - 3rd Ed.2016 - Add.2-2020 - Risk-Based Inspection Methodology

RISK-BASED INSPECTION METHODOLOGY, PART 5—SPECIAL EQUIPMENT 5-17
Bbl = for t ≥ t
(5.49)
leak
groundwater, n
0
gl ld
Bbl = Bbl − Bbl
(5.50)
leak leak leak
subsoil, n n groundwater,
n
f) STEP 12.6 – Determine the environmental financial consequence of a leak,
size.
FC
leak
environ
=
3
leak
leak
∑( ,
⋅ +
,
⋅ )
n=
1
Bbl C Bbl C gff
groundwater n groundwater subsoil n subsoil n
gff
tot
FC
leak
environ
, for each hole
(5.51)
g) STEP 12.7 – Determine the total barrels of fluid released by a storage tank bottom rupture,
Bbl
Bbl
⋅ gff
rupture
Bbl .
release
rupture total 4
release
= (5.52)
gfftot
h) STEP 12.8 – Calculate the total barrels of fluid within the dike from a rupture,
of fluid in the on-site surface soil,
Bbl −
rupture
ss offsite
Bbl −
rupture
ss onsite
, and the total barrels of fluid that reach water,
Equation (5.29), respectively.
rupture
Bbl , the total barrels
indike
, the total barrels of fluid in the off-site surface soil,
Bbl
leak
water
, using Equation (5.26) through
i) STEP 12.9 – Calculate the financial environmental cost for a storage tank bottom rupture,
using Equation (5.30) where
rupture
Bbl ,
indike
rupture
Bblss −
,
onsite
Bbl −
rupture
ss offsite
, and
rupture
FC ,
environ
leak
Bbl are from STEP 12.8.
water
j) STEP 12.10 – Calculate the total financial environmental cost from a leak and a rupture, FC
environ
Equation (5.51) where
leak
FC is from STEP 12.6 and
environ
rupture
FC is from STEP 12.9.
environ
, using
k) STEP 12.11 – Calculate the component damage cost, cmd , using Equation (5.53) with the release
hole size damage costs from Part 3, Table 4.15 and generic failure frequencies for the release hole sizes
from STEP 2.3. The material cost factor, matcost , is obtained from Part 3, Table 4.16.
FC
FC
cmd
2
⎛ 3
⎛D
⎞ ⎞
tank
⎜∑
gffn⋅ holecostn + gff4
⋅holecost4⋅ ⎜ ⎟
n=
1 C ⎟
36
=
⎜
⎝ ⎠ ⎟
⎜
⋅ matcost
gff
⎟
total
⎜
⎟
⎝
⎠
(5.53)
The parameter,
⎛
⎜
⎝
D tank
C
36
⎞
⎟
⎠
2
, is a cost adjustment factor for a storage tank bottom replacement. The cost
factor included in Part 3, Table 4.15 is normalized for a storage tank with a diameter of 30.5 m (100 ft),
and this factor corrects the cost for other storage tank diameters.
l) STEP 12.12 – Calculate the total financial COF, FC
total , using Equation (5.54).
FCtotal = FCenviron + FCcmd + FC
(5.54)
prod
Nomenclature