The Where, What and How of Oil Drilling
When many of us hear the word oil, it conjures up for us a picture of Jed and Granny in the opening of the show the "Beverly Hillbillies". (1) If only things were that simple and wholesome! The process of locating, drilling, extracting and refining oil is a long, time-consuming, energy- demanding process. The various steps of this process and the resulting use of an array of petroleum products, raises havoc with the earth's fragile environment.
The meaning of the word petroleum translates to "rock oil" or "oil from the earth". Oil results from decaying marine organisms that formed into anaerobic sedimentary layers between ten and six hundred million years ago. Anaerobic bacteria decomposed the detritus into rich organic material, which blend with sediments to form these layers of shale. As these layers form and build, heat and pressure transform the organic material into crude oil and natural gas. The oil flows into more porous rock called the reservoir rock, where the oil and gas become trapped between more impermeable types of rock called cap rock. Geologists are skilled in finding oil based on their knowledge of how these rocks form and looking at surface rock features and soil types in conjunction with satellite images. More recently, the technique of finding flowing oil through the use of equipment that measures the earth's magnetic field has been employed. The reasoning is that the movement of the oil creates a change in the magnetic field. The most recognized method of detection of oil is through seismic activity. Everything from explosives to air guns are used to create a shock wave through the buried rock layers. When the waves are returned to the surface, seismologists interpret them to help the geologist determine if the site is a feasible drilling site. (2)
Once a site has been deemed a drilling site and given coordinates, the legalities of the use of the land or off -shore sites must be dealt with. This may be followed by required or requested studies to be completed to determine what the impacts might be on the environment from the drilling process and all of its associated activities. Roads to the site are built and plans for any by-products of the operation must be made. In the case of land drilling, a water source must be located and available due to the fact that it is essential in the process of drilling for oil on land. To prepare for the drilling, a cellar is dug around the actual drill hole to make room for the workers and their equipment. (3)
In the case of off –shore drilling, the sensitivity of approval of a site may be more intense. This is where the Exclusive Economic Zone (EEZ) comes into play. This designated area which is a two hundred-mile border from the shores edge out to sea, was claimed by the United States in 1983. Other countries followed suit; being granted the same privileges based on international sea laws. The U.S. federal government manages these areas through the Bureau of Ocean Energy Management, Regulation and Enforcement, which leases these areas to companies. The companies also pay royalties for the oil they harvest from the sea. (4)
The Rig (Use fuel to get fuel.)
Oil for energy cannot be extracted without using a substantial amount of energy. The power system, which drives the mechanics of the rig, is powered by electricity, which is provided by a generator, fueled by diesel engines. A drill bit, which is appropriate for the type of rock, is located at the end of the drill, which works in a rotating motion. The drill pipe is surrounded by a collar, which puts weight on the drill bit. The drill hole is lined with cement to prevent the hole from collapsing and the mud used for the drilling to move through the system. The "mud" is water and clay mixed with chemicals and "weighting materials" that help to move the rock to the surface. A derrick is the structural frame that holds the drill, and last but not least the blowout preventer consists of valves that seal the high- pressure lines and vent excessive pressure to prevent a blowout of gas or oil that will rise to the waters surface as it did at the Deepwater Horizon site, causing a deadly fire. To extract oil, a pump is installed after the rig is removed. Offshore drilling comes with increased risks. Mobile Offshore Drilling Units (MODU) are used to dig the original well and then some of them are converted to pumping production rigs. (5)
The crude oil obtained through drilling is then transported to refineries to be converted into various petroleum products. When crude oil is refined a 6% product gain is obtained through the process. A barrel of refined crude oil usually results in a variety of products including diesel and jet fuel, gasoline and other distillates. Harvested oil is put through hot furnaces where it separates into liquids and vapors which further separate by weight in distillation towers. The heavier products are then manipulated to produce a lighter more valuable product, like gasoline. After these conversions, various degrees of final treatments are performed depending on the desired product. These products are then transported through pipelines, by tankers and land transportation vehicles. Each one of these transportation methods opens up the possibility of oil spilling into various environments. (6)
History of Gulf Oil
The oil industry in Louisiana intensified in the early 1900s. Fisherman traded their jobs for money in the field of oil, with little education. They shared the Gulf grounds with the oil platforms to make their living. Oil and gas were plentiful due to the large, long-term sediment deposits from the Mississippi River and the salt layers of the Gulf. Challenges associated with moving offshore made the progression slow and costly. Concerns ranged from everyday issues such as the work environment to acute situations including blowouts and platform destruction as a result of storms.
As demands for oil skyrocketed following the close of fuel rations at the end of World War II, the drive for technological advancement soared. (7) Exxon pioneered the use of "jackets" on the platforms, which resulted in a stronger structure, less likely to be damaged by the elements. Mobile submersibles appeared in the 1950s, and were leased per Diem, resulting in the development of two of the Gulf's biggest oil fields. (7A) Off shore wells were proving to have higher returns than their on shore partners. By the late 1950s, advancement into deep waters was delayed when the reality of these rigs not handling conditions in deeper waters became a reality. In the early sixties a "floating drilling platform" was introduced by Shell. The" semi-submersible" was expected to allow exploration up to six hundred feet deep. Shell opened up the industry by sharing their technology. This resulted in vast tracts of land being leased by many companies in search of a fortune in oil. The Gulf's total harvests rose from approximately 350,000 barrels/day in 1962, to 915,000 barrels/day in 1968. (7B) But as the end of the 60s approached, leases were not as productive and it become more and more difficult to make a decent profit with oil bringing in such a low price per barrel.
As the race to bring in product intensified, the focus on safety blurred. Mobile units meant more potential for accidents. Inspections were not routine due to lack of money and inspectors. Lack of equipment inspections meant more frequent accidents. The blowout of a California well in 69 resulted in the Interior Department implementing the first "rules" controlling the leasing of land in areas that the department deemed environmentally risky. (7C) As more accidents occurred, more revisions were made to these rules. More inspectors ere hired and an inspection program was put into place with new guidelines and standards for mobile drilling. Through the 70s and 80s the number of blowouts remained constant, but the severity of the blowouts lessened. The reduction in the number of explosions meant fewer injuries and deaths. (7D)
In 1973 the OPEC oil embargo inspired domestic companies to further develop offshore sites. In 1975 Shell developed a new technique allowing them to drill in 1000 feet of water. But in 1980 the average drilling depth was still only 200 feet. Many of the new leases did not produce expected results. (7E) Then geologists discovered "turbidites" or "mini-basins" of oil at the edge of the continental shelf and predicted offshore basins to be larger in volume. These findings prompted the Department of Interior to launch a system of "area-wide offshore leasings". (7F) But by 1986 oil prices hit rock bottom at $10/barrel due to several years of citizens slowly reducing their dependency on oil as a response to peak prices in the early eighties. (7G) With a lack of funds for further exploration, Shell brings on British petroleum (BP) as a partner in a major project. (7H) As technology advanced in techniques and materials, drilling capabilities increased by thousands of feet and oil flowed from individual deepwater wells at rates of tens of thousands of barrels/day. By the late 90s, one third of the Gulf wells were more than 1500feet deep. (7I) In the late 1990s BP became the largest producer in the Gulf. (7J) As wells moved deeper and deeper into Gulf waters, older platforms on the shelf were dropped to the ocean floor with the intention of providing natural reefs for marine organisms. It appeared as though nothing could stop BP's success, but environmental and safety challenges plagued them as they pushed deeper and deeper, the Macondo blowout being the worst accident in the history of Gulf oil.