Addressing the new global challenges of P&As

Around the world, myriad onshore and offshore oil fields are reaching the end of their productive lives. According to the Environmental Protection Agency, 3.2 million abandoned oil and gas wells exist in the United States. Included in these are thousands of wells drilled more than half a century ago that were not properly plugged and abandoned, Fig. 1.

Fig. 1. A non-producing well from the 1950s.

This is not just a challenge for the U.S., but a global one as well. Wells in the Arabian Gulf, the North Sea and the Caspian Sea, as well as most other offshore areas of the world, are part of this trend. As a result, operators face an upcoming “P&A wave” of wells that need to be permanently plugged and abandoned.

ONSHORE OR OFFSHORE

Whether onshore or offshore, the reasons for P&A are the same. These include:

• Lack of well delivery—The well is no longer productive
• Well problems—Making it not economical for recompletion or doing a workover
• Environmental concerns—Cleaning up the area and not wanting to operate in certain places
• Structural issues—Due to age or hurricane damage.

FROM OLD PROBLEMS…

This proliferation of current and future needs presents unique challenges for operators and well control companies. An abandoned well may present a conduit to the subsurface aquifers below. One abandoned well could contaminate groundwater for miles. Abandoned wells can contaminate groundwater, emit volatile compounds, and leak methane. In the case of older wells, the operation is even more complex, because detailed records of how the well was completed or previously P&A’d or abandoned might not be available. This means operators and service companies must try to determine what is happening underground, based on records of nearby wells. If a well was abandoned decades ago, crews might need to build roads to move the equipment required for the job.

Fig. 2. An orphan well in a wetland.

Operators are already putting huge efforts into making sure that both older wells and newer wells are abandoned properly. However, they are up against unprecedented challenges. For example, there are thousands of orphan oil wells with no leaseholders, and which were originally drilled decades ago when there weren’t strict regulations to follow, to make sure that wells were properly plugged, Fig. 2. In addition, record-keeping was done on paper, so there is no reliable way to get accurate data on the original P&A or know what awaits a Well Control company about to perform a new P&A.

…TO NEW PROBLEMS

As a rule, the Well Control business is 75% workover, completion and production. However, over the past two years, the P&A aspect has become more of a focus for U.S. operators and has taken a larger share of business. In the past 10 years, operators began drilling multi-well pads, which are relatively new in the overall scheme of things. But within 10 more years, we will have multi-well pads that are 20 years old that present a whole new set of P&A challenges. What we do today regarding drilling and production is going to dramatically impact how we do P&As down the road.

For example, drilling and production pads in the Marcellus and Utica shales in the Appalachians are more confined and congested, and everything is tight, which could make the P&A procedure more difficult than previously. What’s more, these wells may be double-valved on the higher pressure rated annuli wellhead assemblies. So, you may not be able to access a valve horizontally, due to cellar design and well spacing. Instead, a right-angle solution for valve drilling is needed to solve the issue. Well spacing, and valve and tree alignment, present a chance for collateral and cascading damages, should a blowout occur, producing a horizontal jet flow and/or fire. Offshore also poses unique challenges, due to space limitations and wellhead valve and tree alignment, as well.

Compounding these hurdles is the fact that there are fewer qualified companies out there with the skills and experience to perform P&As with these issues. The bottom line is that more than ever, P&As require service from well control companies with the specialized skill sets, knowledge bases, tools, and technologies.

REDUCING P&A RISK UPFRONT

Fig. 3. Assessment of an orphan well is critical during the planning stages of a P&A.

The well control community needs to do a better job of communicating possible solutions to customers, to help eliminate concerns. Wells can change hands multiple times in the courses of their lives and because of that, many customers are facing unknown well integrity issues.

Well control company-assisted well integrity programs can make a huge difference in helping the customer avoid needless problems and expenses when P&As are needed. The idea is to help customers substantially reduce risk by involving a well control company in the planning stages of a P&A, so customers are aware of their vulnerabilities before beginning operations, Fig. 3.

With contingency plans in place prior to the P&A, customers can substantially mitigate any types of exposure and reduce costs.

CREATING A SMARTER APPROACH TO P&AS

Fig. 4. Rigging up a pneumatic casing cutter to cut and prepare casing for re-heading.

Operators are in the business of drilling and producing, not P&A. Typically, operators don’t have the manpower or resources required to perform a P&A—especially one with issues—and don’t have the staff to dedicate to P&A. It’s also important for customers to have all the products, services, and technology to meet the complete needs of a P&A.

For example, our bundled services from cementing to coil, to downhole tools, engineers, flowback tanks, hot tap, valve drilling, freeze services, etc., fill the gaps of traditional service companies to perform a P&A, Fig. 4. There is one contact that makes it easier for customers to handle the project from start to finish.

The fewer contracts that customers must deal with is smart for both financial and efficiency reasons. They don’t have to worry about the liabilities of using 10 different companies, 10 different insurances, 10 different safety cultures, and 10 different pricing practices. Instead, they have one provider to meet their complete P&A needs with the products, services and technology required to be prepared for the unexpected.

ENSURING WELL INTEGRITY WITH TECHNOLOGY

Fig. 5. Tapping, using a hot-tap unit to check for trapped pressure.

The detailed operations required in a P&A can vary significantly from well to well, depending on the type of well and the actual well conditions. A critical part of P&A is assessing well integrity prior to an abandonment. Technology plays a major role in this. For example, we have a mobile Wellhead Audit application that inspects wellheads and identifies in minutes which wells need immediate attention and which wells are of minimal or moderate risk. This is a highly efficient way for customers to know whether their assets present risk and take steps to rectify the issue before the risk becomes an unwanted issue that can escalate.

Technologically advanced hot tap, valve drilling units and freezes may be a key to the P&A preparation process, depending on the well, Fig. 5. Today’s valve drilling machines are lighter and more efficient than previously available. Freezes are now being performed with field people. These folks are engineers that continually improve technologies and are coming with solutions to handle congested well bays, and lack of horizontal and vertical access on offshore structures.

In the area of hot taps, Cudd Well Control has developed a new ultra-compact Hot Tap that is less than 10% the weight of conventional equipment, and the only hot tap on the market rated API 6A 3G. This highly safe technology, used to check pressures, offers a compact design that makes it easy to transport and easy to use by one worker.

STEPPING UP TO THE CHALLENGE TOGETHER

Plugging and abandoning the scores of orphaned oil and gas wells presents an opportunity to mitigate problems and potential risks, and provide an economic boost to the experts that specialize in this area. Employment gains from plugging wells could help offset job losses from the oil and gas industry, which lost tens of thousands of jobs during the Covid-19 pandemic. While there is much work still to be done on the issue, a concerted effort by the Well Control community is a promising step to meeting the environmental and economic goals of customers around the world.

About the Authors

Collin Simmons

Cudd Well Control

Collin Simmons is an Operations project manager for Cudd Well Control. He has over 10 years in the oil and gas industry holding multiple positions, including pressure control engineer, Special Services engineer and well site manager overseeing completion, production and workover operations for major oil and gas operators. Mr. Simmons holds a BS degree in Construction Engineering Management from Missouri Western State University.

Larry Nixon

Cudd Well Control

Larry Nixon serves as a senior technical advisor for Cudd Well Control. He has nearly 40 years of critical well intervention knowledge in the prevention, control and mitigation of industry incidents. Mr. Nixon’s experience has taken him around the globe, tackling many of the toughest, unpredictable, well control events with a command that has led to quick and safe engineered resolutions.