EPA FRP WCD volume, how does one calculate? – An OPA90 Discussion

I hope everyone is off to a good start this Monday. I am back from Clean Gulf this week, where Witt O’Brien’s had another successful year, and I was able to catch up with a lot former colleagues, friends, and clients. You can see pictures of, and read about Witt O’Brien’s participation this year in more detail below by clicking the link to Witt O’Brien’s LinkedIn page.

Moving forward, let me dive into the final chapter of my mini-series focused on the Oil Pollution of Act of 1990 (OPA90) Worst Case Discharge (WCD) planning volume determinations for the three inland federal agencies: the U.S. Coast Guard (USCG); the Environmental Protection Agency (EPA); and the Department of Transpiration’s (DOT) Pipeline and Hazardous Materials Safety Administration (PHMSA). This week, I’ll address EPA’s Facility Response Plan (FRP) WCD planning volumes.

As always, let’s first see what the rule says:

Appendix D to Part 112—Determination of a Worst Case Discharge Planning Volume

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.

Let’s break the above down, and I’ll do so by addressing each scenario individually as discussed under 1.2, 1.3 and 1.4 respectively.

1.2, on-shore operations, meaning, anything not associated with production facilities and wells as defined under 112.10 and 112.11. Out of all the OPA90 requirements for WCD, this is the easiest, as it’s tank based only and represents 90% of OPA90 plans under EPA’s jurisdiction. You have four considerations here in determining your facility’s WCD. First, if no tanks are openly manifolded together, and you have proper containment, it’s the largest tank - easy enough. If you have tanks that are permanently manifolded together, and the valves that connect them are kept open and piping is at a level allowing volume sharing, these tanks will be considered one large tank; thus, your WCD volume would be the aggregate of all tanks permanently manifolded together. Typically, this second scenario is found at tank batteries in up-stream only. Third, and an interesting allowance the EPA provides under this rule for facilities that have only one tank, is if the facility has adequate containment too, one can reduce the WCD volume by multiplying this volume by 0.8. The last scenario, which also means you’re in violation of the rule, is when one has insufficient containment as defined under the rule, which then requires you to account for the largest tank plus all other tanks that lack sufficient containment.

1.3, production and exploration facilities associated with wells is honestly probably one of the more confusing OPA90 WCD volume determinations there is. The EPA explains how to do this in attachment D.1 found under Appendix D of the rule.  That is a long discussion, so be before diving into it, let’s address 1.4. For 1.4 you’ll need to complete the exercise found here for the USCG WCD, and also 1.2 and 1.3 discussed here. Both volumes will need to be displayed in your FRP; however, the larger of the two, generally always the EPA, will be the overall WCD for the facility.

Warning, from here on, this gets a little mind-numbing with the amount of details required for 1.3.

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

4All 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.

 

Before going too far, are you a visual person? Here’s an example of the above.

Oil storage capacity of tanks without adequate secondary containment = 1,320 barrels

For wells deeper than 10,000 feet: Method B

Production Volume = Discharge Volume 1 + Discharge Volume 2

Discharge Volume 1 = (Days unattended + Days to respond) x (Rate of well [Barrels Per Day])

   = (0 day + 0.5 days) X (100 BPD)

   = 50 barrels or 2,100 gallons

Discharge Volume 2 = [45 days - (days unattended + days to respond)] x [(rate of well) x (rate of well/rate of recovery)]

    = [45 days - (0 day + 0.5 days)] X [(100 BPD) x (100/100)]

   = 4,450 barrels or 186,900 gallons

 WCD = 1,320 barrels + 50 barrels + 4,450 barrels = 5,820 barrels or 244,440 gallons

What does the rule say? It’s long; however, here you go:

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

2017 EPA OPA90 FRP Compliance Series:+

• Fact vs. Myth – EPA FRP Training Requirements – An OPA90 Discussion
• OPA90/Contingency Plans Post Harvey/Irma - Have your Facilities/Operations Changed?
• How to Select an OSRO - Inland OPA90 Conversation
• Am I EPA, USCG, or PHMSA Regulated (OPA90 Jurisdictional Conversation)
• EAP vs. FRP: Doesn’t my FRP address this already? (OSHA-OPA90 Discussion)
• Am I Required to use ICS at my Facility? (OPA90 Discussion)
• How Much Boom Do I Need? (OPA90 Discussion)
• What is an EPA FRP 5-Year Review?
• What really is a QI under OPA90: EPA; USCG; PHMSA?
• I have a submitted FRP, it is vetted and approved, right? EPA-FRP, USCG-FRP, PHMSA-OSRP
• “I just bought an oil terminal, now what?” ICP Timelines - EPA, USCG, PHMSA Requirements
• Did you know the National Preparedness for Response Exercise Program (PREP) Guidelines were updated?
• Is Your Contingency Plan Compliant and Mindful of Current Industry Conditions?

For a complete listing of archived blogs and resources, click here.

Need OPA90 or other planning assistance or just have a question? Email John Carroll ([email protected]), Associate Managing Director - Compliance Services at Witt O’Brien’s or reach him by phone at 281-320-9796.

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