Appendix D to Part 112 - Determination of a Worst Case Discharge Planning Volume
40:24.0.1.1.7.4.6.3.4 : Appendix D
Appendix D to Part 112 - Determination of a Worst Case Discharge
Planning Volume 1.0 Instructions
1.1 An owner or operator is required to complete this worksheet
if the facility meets the criteria, as presented in appendix C to
this part, or it is determined by the RA that the facility could
cause substantial harm to the environment. The calculation of a
worst case discharge planning volume is used for emergency planning
purposes, and is required in 40 CFR 112.20 for facility owners or
operators who must prepare a response plan. When planning for the
amount of resources and equipment necessary to respond to the worst
case discharge planning volume, adverse weather conditions must be
taken into consideration. An owner or operator is required to
determine the facility's worst case discharge planning volume from
either part A of this appendix for an onshore storage facility, or
part B of this appendix for an onshore production facility. The
worksheet considers the provision of adequate secondary containment
at a facility.
1.2 For onshore storage facilities and production facilities,
permanently manifolded oil storage tanks are defined as tanks that
are designed, installed, and/or operated in such a manner that the
multiple tanks function as one storage unit (i.e., multiple tank
volumes are equalized). In a worst case discharge scenario, a
single failure could cause the discharge of the contents of more
than one tank. The owner or operator must provide evidence in the
response plan that tanks with common piping or piping systems are
not operated as one unit. If such evidence is provided and is
acceptable to the RA, the worst case discharge planning volume
would be based on the capacity of the largest oil storage tank
within a common secondary containment area or the largest oil
storage tank within a single secondary containment area, whichever
is greater. For permanently manifolded tanks that function as one
oil storage unit, the worst case discharge planning volume would be
based on the combined oil storage capacity of all manifolded tanks
or the capacity of the largest single oil storage tank within a
secondary containment area, whichever is greater. For purposes of
this rule, permanently manifolded tanks that are separated by
internal divisions for each tank are considered to be single tanks
and individual manifolded tank volumes are not combined.
1.3 For production facilities, the presence of exploratory
wells, production wells, and oil storage tanks must be considered
in the calculation. Part B of this appendix takes these additional
factors into consideration and provides steps for their inclusion
in the total worst case discharge planning volume. Onshore oil
production facilities may include all wells, flowlines, separation
equipment, storage facilities, gathering lines, and auxiliary
non-transportation-related equipment and facilities in a single
geographical oil or gas field operated by a single operator.
Although a potential worst case discharge planning volume is
calculated within each section of the worksheet, the final worst
case amount depends on the risk parameter that results in the
greatest volume.
1.4 Marine transportation-related transfer facilities that
contain fixed aboveground onshore structures used for bulk oil
storage are jointly regulated by EPA and the U.S. Coast Guard
(USCG), and are termed “complexes.” Because the USCG also requires
response plans from transportation-related facilities to address a
worst case discharge of oil, a separate calculation for the worst
case discharge planning volume for USCG-related facilities is
included in the USCG IFR (see appendix E to this part, section 13,
for availability). All complexes that are jointly regulated by EPA
and the USCG must compare both calculations for worst case
discharge planning volume derived by using the EPA and USCG
methodologies and plan for whichever volume is greater.
PART A: WORST CASE DISCHARGE PLANNING VOLUME CALCULATION FOR
ONSHORE STORAGE FACILITIES 1
1 “Storage facilities” represent all facilities subject to this
part, excluding oil production facilities.
Part A of this worksheet is to be completed by the owner or
operator of an SPCC-regulated facility (excluding oil production
facilities) if the facility meets the criteria as presented in
appendix C to this part, or if it is determined by the RA that the
facility could cause substantial harm to the environment. If you
are the owner or operator of a production facility, please proceed
to part B of this worksheet.
A.1 SINGLE-TANK FACILITIES
For facilities containing only one aboveground oil storage tank,
the worst case discharge planning volume equals the capacity of the
oil storage tank. If adequate secondary containment (sufficiently
large to contain the capacity of the aboveground oil storage tank
plus sufficient freeboard to allow for precipitation) exists for
the oil storage tank, multiply the capacity of the tank by 0.8.
(1) FINAL WORST CASE VOLUME: __ GAL
(2) Do not proceed further.
A.2 SECONDARY CONTAINMENT - MULTIPLE-TANK FACILITIES
Are all aboveground oil storage tanks or groups of
aboveground oil storage tanks at the facility without
adequate secondary containment? 2
2 Secondary containment is described in 40 CFR part 112,
subparts A through C. Acceptable methods and structures for
containment are also given in 40 CFR 112.7(c)(1).
__ (Y/N)
A.2.1 If the answer is yes, the final worst case discharge
planning volume equals the total aboveground oil storage
capacity at the facility.
(1) FINAL WORST CASE VOLUME: __ GAL
(2) Do not proceed further.
A.2.2 If the answer is no, calculate the total aboveground oil
storage capacity of tanks without adequate secondary containment.
If all aboveground oil storage tanks or groups of
aboveground oil storage tanks at the facility have adequate
secondary containment, ENTER “0” (zero).
__ GAL
A.2.3 Calculate the capacity of the largest single aboveground
oil storage tank within an adequate secondary containment area or
the combined capacity of a group of aboveground oil storage tanks
permanently manifolded together, whichever is greater, PLUS THE
VOLUME FROM QUESTION A.2.2.
FINAL WORST CASE VOLUME: 3 __ GAL
3 All complexes that are jointly regulated by EPA and the USCG
must also calculate the worst case discharge planning volume for
the transportation-related portions of the facility and plan for
whichever volume is greater.
PART B: WORST CASE DISCHARGE PLANNING VOLUME CALCULATION FOR
ONSHORE PRODUCTION FACILITIES
Part B of this worksheet is to be completed by the owner or
operator of an SPCC-regulated oil production facility if the
facility meets the criteria presented in appendix C to this part,
or if it is determined by the RA that the facility could cause
substantial harm. A production facility consists of all wells
(producing and exploratory) and related equipment in a single
geographical oil or gas field operated by a single operator.
B.1 SINGLE-TANK FACILITIES
B.1.1 For facilities containing only one aboveground oil storage
tank, the worst case discharge planning volume equals the capacity
of the aboveground oil storage tank plus the production volume of
the well with the highest output at the facility. If adequate
secondary containment (sufficiently large to contain the capacity
of the aboveground oil storage tank plus sufficient freeboard to
allow for precipitation) exists for the storage tank, multiply the
capacity of the tank by 0.8.
B.1.2 For facilities with production wells producing by pumping,
if the rate of the well with the highest output is known and the
number of days the facility is unattended can be predicted, then
the production volume is equal to the pumping rate of the well
multiplied by the greatest number of days the facility is
unattended.
B.1.3 If the pumping rate of the well with the highest output is
estimated or the maximum number of days the facility is unattended
is estimated, then the production volume is determined from the
pumping rate of the well multiplied by 1.5 times the greatest
number of days that the facility has been or is expected to be
unattended.
B.1.4 Attachment D-1 to this appendix provides methods for
calculating the production volume for exploratory wells and
production wells producing under pressure.
(1) FINAL WORST CASE VOLUME: __ GAL
(2) Do not proceed further.
B.2 SECONDARY CONTAINMENT - MULTIPLE-TANK FACILITIES
Are all aboveground oil storage tanks or groups of
aboveground oil storage tanks at the facility without
adequate secondary containment?
__ (Y/N)
B.2.1 If the answer is yes, the final worst case volume equals
the total aboveground oil storage capacity without adequate
secondary containment plus the production volume of the well with
the highest output at the facility.
(1) For facilities with production wells producing by pumping,
if the rate of the well with the highest output is known and the
number of days the facility is unattended can be predicted, then
the production volume is equal to the pumping rate of the well
multiplied by the greatest number of days the facility is
unattended.
(2) If the pumping rate of the well with the highest output is
estimated or the maximum number of days the facility is unattended
is estimated, then the production volume is determined from the
pumping rate of the well multiplied by 1.5 times the greatest
number of days that the facility has been or is expected to be
unattended.
(3) Attachment D-1 to this appendix provides methods for
calculating the production volumes for exploratory wells and
production wells producing under pressure.
(A) FINAL WORST CASE VOLUME: __ GAL
(B) Do not proceed further.
B.2.2 If the answer is no, calculate the total aboveground oil
storage capacity of tanks without adequate secondary containment.
If all aboveground oil storage tanks or groups of
aboveground oil storage tanks at the facility have adequate
secondary containment, ENTER “0” (zero).
__ GAL
B.2.3 Calculate the capacity of the largest single aboveground
oil storage tank within an adequate secondary containment area or
the combined capacity of a group of aboveground oil storage tanks
permanently manifolded together, whichever is greater, plus the
production volume of the well with the highest output, PLUS THE
VOLUME FROM QUESTION B.2.2. Attachment D-1 provides methods for
calculating the production volumes for exploratory wells and
production wells producing under pressure.
(1) FINAL WORST CASE VOLUME: 4 __ GAL
4 All complexes that are jointly regulated by EPA and the USCG
must also calculate the worst case discharge planning volume for
the transportation-related portions of the facility and plan for
whichever volume is greater.
(2) Do not proceed further.
Attachments to Appendix D Attachment D-I - Methods To Calculate
Production Volumes for Production Facilities With Exploratory Wells
or Production Wells Producing Under Pressure 1.0 Introduction
The owner or operator of a production facility with exploratory
wells or production wells producing under pressure shall compare
the well rate of the highest output well (rate of well), in barrels
per day, to the ability of response equipment and personnel to
recover the volume of oil that could be discharged (rate of
recovery), in barrels per day. The result of this comparison will
determine the method used to calculate the production volume for
the production facility. This production volume is to be used to
calculate the worst case discharge planning volume in part B of
this appendix.
2.0 Description of Methods
2.1 Method A
If the well rate would overwhelm the response efforts (i.e.,
rate of well/rate of recovery ≥1), then the production volume would
be the 30-day forecasted well rate for a well 10,000 feet deep or
less, or the 45-day forecasted well rate for a well deeper than
10,000 feet.
(1) For wells 10,000 feet deep or less:
Production volume = 30 days × rate of well.
(2) For wells deeper than 10,000 feet:
Production volume = 45 days × rate of well.
2.2 Method B
2.2.1 If the rate of recovery would be greater than the well
rate (i.e., rate of well/rate of recovery <1), then the
production volume would equal the sum of two terms:
Production volume = discharge volume1 + discharge volume2
2.2.2 The first term represents the volume of the oil discharged
from the well between the time of the blowout and the time the
response resources are on scene and recovering oil (discharge
volume1).
Discharge volume1 = (days unattended + days to respond) × (rate of
well)
2.2.3 The second term represents the volume of oil discharged
from the well after the response resources begin operating until
the discharge is stopped, adjusted for the recovery rate of the
response resources (discharge volume2).
(1) For wells 10,000 feet deep or less:
Discharge volume2 = [30 days−(days unattended + days to respond)] ×
(rate of well) × (rate of well/rate of recovery)
(2) For wells deeper than 10,000 feet:
Discharge volume2 = [45 days−(days unattended + days to respond)] ×
(rate of well) × (rate of well/rate of recovery) 3.0 Example
3.1 A facility consists of two production wells producing under
pressure, which are both less than 10,000 feet deep. The well rate
of well A is 5 barrels per day, and the well rate of well B is 10
barrels per day. The facility is unattended for a maximum of 7
days. The facility operator estimates that it will take 2 days to
have response equipment and personnel on scene and responding to a
blowout, and that the projected rate of recovery will be 20 barrels
per day.
(1) First, the facility operator determines that the highest
output well is well B. The facility operator calculates the ratio
of the rate of well to the rate of recovery:
10 barrels per day/20 barrels per day = 0.5 Because the ratio is
less than one, the facility operator will use Method B to calculate
the production volume.
(2) The first term of the equation is:
Discharge volume1 = (7 days + 2 days) × (10 barrels per day) = 90
barrels
(3) The second term of the equation is:
Discharge volume2 = [30 days - (7 days + 2 days)] × (10 barrels per
day) × (0.5) = 105 barrels
(4) Therefore, the production volume is:
Production volume = 90 barrels + 105 barrels = 195 barrels
3.2 If the recovery rate was 5 barrels per day, the ratio of
rate of well to rate of recovery would be 2, so the facility
operator would use Method A. The production volume would have
been:
30 days × 10 barrels per day = 300 barrels [59 FR 34110, July 1,
1994; 59 FR 49006, Sept. 26, 1994, as amended at 65 FR 40800, June
30, 2000; 67 FR 47152, July 17, 2002]