Ever since the ancient Greek demigod Prometheus scaled the peaks to steal fire from an agitated Zeus, gathering energy for the use of mankind has been fraught with unforeseen consequences. Prometheus got himself into a grave situation. Zeus, in his anger, bound him to a stone where an eagle devoured his liver by day; each night the organ grew back, and the cycle was repeated very next day. Fortunately, Prometheus had a rescuer. Heracles freed him from his torment and sent him to make trouble elsewhere.
From the hazards of the woodcutting life in the forests of old to whaling on the high seas and today’s deep-ocean drilling and land-based fracking, energy extraction, almost by definition, has been a risky undertaking. Our problem is that we can’t rely on the aid of benevolent demigods. As demand mounts and technology races to meet the task, even today we often must deal with unforeseen consequences in meeting these needs.
A good portion of the newly discovered petrochemical potential in places far from the conventional crude drilling sites in Texas and Oklahoma can be attributed to technological advances. Among the most stunning, productive, and controversial of these are hydrofracturing processes and horizontal drilling.
Some say taking advantage of the technology, and the resources that fracking can help generate, could save society a lot of grief; others argue the opposite. The controversies surrounding hydraulic fracturing are innumerable, ranging from the debate over whether our continued reliance on hydrocarbon fuels is a prudent strategy for society, to complaints from individuals with damage claims focused on particular fracking installations.
Nonetheless, these high-tech petrochemical extraction operations are on the march in regions ranging from the Dakota Badlands to the Appalachian valleys, the flatlands of the Midwest to the traditional oil-and-gas sites of the Southern plains.
Alex Demas, a public affairs specialist with the US Geological Survey who has been covering energy resources over the past four years, notes that “hydrofracking is just one component” of a suite of new techniques now being used to extract and collect petrochemical resources that, not long ago, would have been considered inaccessible.
He offers a brief explanation of how the technique works. Picture the dark-colored streaks of rock along vertical rock faces through which highways are cut in the hills of Pennsylvania or West Virginia; the stone visible from the roadways is not as “solid” as it appears. These rocks are highly porous shales. “In just about all rock formations, there are little spaces between certain parts of the rock that are called pore spaces,” he says. In shales endemic to these areas, “It’s these pore spaces that typically contain the oil and gas.”
He notes, “In areas where conventional drilling is practiced, the pore spaces are large and interconnected, so all you have to do is sink a well down there, create an opening, and the oil and gas will flow through the large interconnected pores to the well bore,” where it can be pumped to the surface. However, in other types of rock formations the pores are much smaller and are not well connected to one another. The USGS refers to these as “tight formations.” In these formations, pore spaces, in fact, are measured on the scale of nanometers to micrometers, yet they can be rich with gas or petroleum. And because there are a great number of such pores in the masses of rock in a shale formation, the petroleum can be of significant volume. But to get at those resources, Demas says, “you have to artificially create pathways for the oil and gas to flow.”
Hydraulic fracturing operations are a method of creating these pathways, “pumping down water and chemicals under high pressure to pry apart the rock” and usually introducing “some kind of sand” to the solutions to keep the fractures open to extract the petrochemicals, Demas explains.
The deposits of rock containing valuable hydrocarbons can take on a number of different configurations. They can be in folds close to the surface or buried thousands of feet underground. “It all depends on how they’ve been affected by Earth forces” over geologic time, Demas says. After locating these subsurface formations and noting where petrochemical deposits are likely to be encountered, extraction companies target the various strata and bore their wells to probe them.
Demas says that sometimes upon reaching the depth of the targeted hydrocarbon-bearing rock, operators employ directional drilling, angling the bore on a diagonal or horizontal slant, then drilling sideways through the rock to maximize the bore’s passage through the layer containing shales permeated with oil or natural gas. At times, a unit called a perforating rod is sent down the shaft and out into the horizontal leg. Equipped with explosive charges, the perforating rod cracks the surrounding rock to interconnect the pores and begin the release of hydrocarbons. According to Demas, through this finely tuned engineering process specialists can predict “with a fair degree of certainty” what direction and to what degree these cracks will proliferate to establish a pathway for petroleum from innumerable tiny pores within the rock to reach the wellhead.
Fish Cry Foul
But it’s not necessarily a smooth process. Along with the oil or gas, the pores contain additional material that may also pumped be to the surface through the hydraulic fracturing process. Water is one prominent waste product, but it’s water that has resided in the pores over eons and carries highly concentrated levels of various salts that occur naturally within porous rock. According to the USGS, “Produced water quality varies significantly based on geographical location, type of hydrocarbon produced, and the geochemistry of the producing formation. In general, the total dissolved solids concentration can range from 100 milligrams per liter [mg/L] to over 400,000 mg/L.” These waters also may carry the organic compounds benzene, toluene, ethylbenzene, the agency reported in Oil and Gas Produced Water Management and Beneficial Use in the Western United States. With salt concentrations sometimes 120 times that of seawater, produced water is a known environmental hazard and must usually be sequestered and carefully managed once it is brought to the surface.
Beyond just the produced water, a certain fraction of the spent fracking solutions themselves return to the surface during petrochemical extraction. They too must be carefully managed; Demas says USGS studies have shown either of these materials can have a detrimental impact on the environment if they are not properly controlled.
For instance, in the aftermath of a fish kill on Kentucky’s Acorn Fork in 2007, USGS scientists determined “hydraulic fracturing solutions that had spilled from nearby natural gas well sites to be the cause of the widespread death or distress of aquatic species.”
Nevertheless, hydraulic fracturing seems likely to remain a growth industry into the foreseeable future. At the recent Bakken Oil and Gas Show, experts revealed that South Dakota has greatly increased its output, much of it through drilling or hydraulic fracturing, and that neighboring North Dakota, using the same technologies, now produces upwards of a million barrels per day, possibly surpassing Texas in production. But in the midst of such a boom, they point out, it is critical well to minimize environmental impacts in the process. Part of that solution he said is effective erosion control.
Fracking operations have already begun to proliferate beyond the traditional oil and gas drilling capitals like Texas and Oklahoma and are projected to spread even more widely through the United States-in rural districts, urban districts, forested landscapes, mountains, stream valleys, and towns, some of which have never experienced industrial development on any scale.
For example, the state of Ohio sits atop two notable reserves that would be accessible through hydrofracturing. Between the Marcellus Shale, which stretches from New York to Kentucky and west into Ohio, and the Utica Shale, which lies thousands of feet below the Marcellus and stretches from the St. Lawrence Lowlands of Quebec to Kentucky, experts believe that three-fourths of the state of Ohio rests atop oil or natural gas resources. Ray Swartzwelder, CEO of Weaver Express, a major player in erosion control services in the oil and gas industry, says there are currently about 800 wells that have begun to tap into this resource, and projections indicate that to fully exploit the resource would require nearly 10,000 additional wells. And with our unremitting quest for fire, there is little reason to think many of them won’t be forthcoming. However, developing these resources, by definition, will require land disturbance on a massive scale. Mitigating the impact of that disturbance is the specialty of erosion control specialists.
Heading Off Erosion at the Pass
“Anytime you do construction, you have to have some form of erosion control,” notes Swartzwelder. His company supplies erosion control services for two types of projects in the field, well pads and pipelines, and is the largest user of Filtrexx products in the oil and gas industry.
In Swartzwelder’s view, there are at least two major challenges facing erosion control activities on an oil-and-gas project. The first is the remote and often undulating character of the terrain “with lots of rivers and streams.” The second relates to public relations. The atmosphere of controversy around energy and energy production in society at large motivates a fair amount of public scrutiny of drilling activities. “Folks who are not necessarily fans of fracking or drilling are observing how oil-and-gas companies behave,” he says. But in response, he notes, some the biggest energy companies in the industry “have evolved over time to have world-class erosion sediment control protection. Their sites are pristine; they do a great job building them. And having an effective erosion control method is a very important part of limiting the environmental impact of oil-and-gas drilling.”
Swartzwelder says one of the reasons his firm has been successful dealing with the logistical issues on the varied terrain of oil-and-gas sites is its specialized equipment. The company developed the first track pneumatic blower truck in the industry in 2008 by reconfiguring by an IHI tractor, adding a mulch blower and computerized control system. He says that unlike a typical blower truck, which is helpless on steep slopes without the aid of a bulldozer to provide towing, Weaver Express blower trucks are capable of getting in an out of the most remote and hilly sites without the need for towing or winching.
The second challenge the company tackles by using the best products and erosion control techniques available to return sites to as pristine a condition as possible. He says Filtrexx FilterSoxx are an immense help to meet this second challenge.
The company recently took on an interesting project in Doddridge County, WV. Drilling pads there can be quite extensive, each covering 10 to 20 acres of undulating terrain, as opposed to the smaller 4-acre pads that are typical in Ohio.
His crews arrive at the beginning of the project. As soon as timbers have been removed and surveyors have staked out the location for erosion control measures, Weaver crews set about installing the compost-filled FilterSoxx, which are biodegradable and come in a variety of sizes ranging from an 8 to 32 inches in diameter.
According to Swartzwelder, The FilterSoxx offer an alternative and more reliable method of erosion and sediment control on oil pad and pipeline projects than silt fences. A fence, he notes, “tries to be a barrier, but if you get a deluge of rain it just gets toppled.” In addition, he says the FilterSoxx are easier to install than silt fence “because you don’t have to trench it.”
For folks without a blower truck, he describes how easily they can be set up on a pipeline installation. “You load prefilled pallets of FilterSoxx on the back of a skid-steer and remove the shrink wrap. Then you drive the skid-steer along the line and pull the sock off as it folds away, until the entire length of the sock is off the skid-steer, then you pound the stakes in and that’s pretty much it.”
He says the biggest adjustment crews who are not familiar with using the product might have to make is dealing with the weight. “Depending on how moist the compost is, the sock weighs between 1,500 pounds and 2,200 pounds.” He recommends first-time installers “practice somewhere else rather than on the job site. You need to know what you’re doing just because of the weight.”
The FilterSoxx have the flexibility to follow the terrain and can be stacked in pyramid formation to provide a strong bulwark against erosion at any point on the slope. “Placed on the low side of the slope, it allows water to pass through the sock, but the sediment and pollutants are trapped in the compost. There’s a chemical composition in the compost that breaks down pollutants, and pore space traps the sediments and prevents that from running offsite.” The diameter of the sock used, he says, depends on the steepness of the slope. “In a flat area or where you don’t have much of a slope, you can use an 8-inch sock. When you get into the hills of West Virginia or Pennsylvania, typically you would use the 32-inch sock, which is pretty hard to visualize unless you’ve seen it, but it’s a pretty large, very heavy sock. The steeper the slope, the more diameter you’re going to need-based on the flow-through chart in the design manuals-to trap the sediment before it runs offsite.”
But it’s not the permanent solution for erosion, he notes. “We’re the very first guys that are in there once they start moving dirt.” But once seeding has successfully achieved 70% growth, protecting the areas downslope of the pipelines or pads with vegetation, he says the FilterSoxx perimeter control can be taken away. “One of the nice things about it is all you have to do is cut the mesh off and spread the compost, and additional vegetation will grow right where the sock was,” he says. “Vegetation is ultimately the best form of erosion control.”
Seeding for Success
Jim Pratt, project coordinator for Pennline Service, with clients in the wind farm and mine reclamation sectors, also provides seeding and revegetation services to clients in the oil-and-gas industry. In his view of the industry, environmental stewardship is essential and the right thing to do. “You’re going in to extract oil from the ground-obviously there are chemicals being used-and restoration is the most important thing, in my eyes, because we’re the last ones to leave and we want to leave it better than we found it. The goal is to be as low impact as possible in everything you do.”
Pratt often uses Profile Products’ 70/30 mulch and Pennington Seed products and services to reseed areas disturbed by oil drilling operations. He recently used Profile’s ProMatrix on a job in northeastern Pennsylvania. “It’s a good product to work with because of its loading capacities,” he notes. A Maruka fitted with a Finn HydroSeeder can be loaded with upward of 1,500 pounds of ProMatrix per tank load. In rough terrain, he says, “What makes it nice is you can get so much material in the tank and use fewer loads per acre.”
The most common challenges he encounters in the field are not peculiar to the nature of the oil-and-gas industry but arise from dealing with logistics and the vagaries of weather: “It’s hard when you have two days of good weather and five days of rain.” However, he notes, “The most challenging thing I see is education.”
One of the things he sees frequently is contractors dealing with the complex landscapes of oil-and-gas country and struggling to use equipment as they might on other types of jobs. That can be a mistake. For instance, he says, before seeding, “the soil has to be prepped by the contractor, and frequently it is difficult to get the contractors to track in the slopes vertically.” Instead they sometimes try to smooth out the slopes with the bulldozer blade as if they were working on a residential landscaping project. He suggests that rather than employing the bulldozer blade as it appears to be intended-to smooth out slopes-contractors should instead make advantageous use of the tracks built into the bulldozer to get up and down those very slopes. “Instead of using your blade, just leave the tracks in there. Each one of those track marks makes a really nice seedbed on the slope and also slows down the erosion process. What I have been seeing is contractors wanting to take the blade and smooth up the slope, and water actually speeds off it faster.
“It all comes back to education,” he continues, “getting everybody on the same page.” He says it’s important to give everybody the “knowledge of the products and how to apply them. A lot of the seed types people use are the wrong seed types for the areas they are being used in.” However, he notes that Brian Free and others at Pennington Seed are helpful in meeting these needs. “Pennington takes soil samples, researching what does well in the area with the types of soils given.” Pratt also appreciates Pennington Seed’s lunch-and-learn forums designed to share important product and technical knowledge with contractors.
When he is done with a project, he says, he wants to see “complete vegetation.” Although he acknowledges that because of the infrastructure it’s not likely that reseeded areas will completely return to forest, he considers reclamation projects successful “as long as they are 100% vegetated and keeping erosion from happening.”
The Cleaning Power of the Internet
Rod Kirch, manager of upstream oil-and-gas sales for GSE, a company that produces impermeable geotextile liners with built-in leak detection that are frequently used to underlay and isolate drilling pads from the surrounding environment, says a higher level of environmental stewardship is gradually working its way onto the scene. He believes it’s not entirely due to regulation. “I think there is good corporate conscience out there that has developed over time. I think land owners and mineral rights owners are becoming more savvy to the fact that at some point somebody is going to get these lands back, so they want them be left in the best possible condition. So when they’re actually negotiating with an energy company or their agents, they want to see protections brought in; they want to see the area cleaned back up and restored to the way it was, as far as possible.
“I think the whole world is becoming more conscience of these things,” he adds. “At one time most of these projects happened in a select few desolate and faraway places miles and miles outside of Midland, TX, where there just aren’t a lot of people. But now, in places like the Marcellus Shale, drilling operations are happening on small family farms, with the tenants or the mineral rights holders living right on the property, so they see what’s going on and they hold these people to a higher standard.”
Kirch believes energy companies also see improved stewardship as a way to promote their brand when vying for valuable production rights from landowners of all types. “They want to be able to say, “˜We came in and we paid a fair price and we did what we said we were going to do, and when we left it was as clean as it was before we started. We’d just like you to tell your neighbors.'”
He notes that the Internet is also a huge factor motivating better stewardship. “Information gets around very quickly. The bad apples get identified; the good apples get identified. People talk about their experiences-there are mineral rights groups and their attorneys, they all talk, and the power of the marketplace works.”Humans will almost certainly want to rely on fire far into the future to get things done, but there is no reason we should not try-unlike Prometheus-to minimize the torment we bring upon ourselves and the rest of the biosphere in the process.