CBM: What About Water?

Of course different attitudes existed towards water, said Steve Szmyd, HSE&C Manager at Wood Group PSN, who offered a coal bed methane (CBM) case study at the Unconventional Gas Forum 2012 in Barcelona, Spain.

He recalled: “”Pindar the Greek poet said water was essential for life; WC Fields countered that he never drank water as it was ‘the stuff that rusts pipe.’”

But for unconventional natural gas plays, water is, of course, a crucial issue.

Presenting “CBM Water Management Strategies and Challenges” as experienced in the Powder River Basin in Wyoming, Mr. Szmyd explained that, “CBM was a water play that produces gas.”

He said that the Basin was 190km by 320km, the largest single source of sub bituminous coal in the US and the basin produced about 400 million tons of coal every year.

“If this basin were in California,” he explained of CBM operations, “it probably never would’ve happened. The people in Wyoming are very energy friendly, they pay low taxes and the income of the state comes in through mining excises, so they’re friendly to the industry.”

Harkening back to the early environmentalist sentiments of American President Theodore Roosevelt, Szmyd spoke of the need to protect the environment, but said it was also necessary to develop mankind – that they didn’t necessarily have to be mutually exclusive. He showed an image of an antelope in Wyoming.

He gave a quick explanation of CBM technology: “The water’s pumped off the coal bed seam, so as soon as you relieve that water pressure, out comes the solution. It produces gas as long as water’s flowing to the well bore.”

According to Szmyd, if one looked at the total produced water distribution from 2009, about 86% of the water – 806 million barrels of water – was handled through impoundments, direct discharge (untreated) and direct discharge (treated); the remaining 15-16% were divided up between surface irrigation, subsurface drip irrigation and underground disposal wells. “So that gives you a feeling for the volume of water that’s dealt with on a yearly basis,” he commented.

He said that the good news was that CBM water had been put to beneficial use.

“Anytime an industry can take its waste product and put it to some other means of use versus just disposal, it’s a good thing. I’ve seen a lot of success stories over the years, avenues like irrigation: farmers, ranchers grow a lot of hay, alfalfa and these are crops that are very salient resistant anyhow. Where these farmers get one cutting of alfalfa for the year under the normal precipitation for the year, with CBM water irrigation they get 3-4 cuttings per year. So with the price of hay and alfalfa high right now, it’s very favorable to them.”

Road application to control dust, and watering livestock were other uses he listed.

“A thirsty cow in the summer can drink 40 liters of water a day. So it may not seem like a lot but over thousands of cattle in the area, it’s significant. More importantly, it establishes those good relations with various property owners and makes for an industry-landowner connection, which is very important,” he explained.

Mr. Szmyd discussed the theory of constraints in connection with coal seam water: “No system is robust: if there’s one leak, then it’s not. So in this overall system of water management, you’ve got regulatory constraints, the water chemistry itself, soil chemistry, your disposal technologies that you have at hand, your capacity constraints, people, financial and wildlife – these must all be met for the system to work properly.”

In terms of regulatory expectations, he said were that one did not harm the air, water, or land. “In Wyoming, there’s a big emphasis on groundwater and also the surface water. There are other agencies that get involved in wildlife considerations and other things, but the main focus is clearly on the water.”

He noted that there was a massive amount of regulation that had to be dealt with and said Wood Group had been very successful in implementing management systems to look at the various critical avenues like permit inventory and compliance plans.

He explained: “There are hundreds of requirements that you need to keep on top of, or the regulators are going to ultimately take exception with your project and could possibly shut you down. It’s a constantly changing environment – we’ve got to stay on top of whatever the latest legislation is that’s coming up.”

Assessments and audits were also crucial, according to Szmyd, who described it as “Being proactive, looking at your operations and staying on top of the situation, so it’s a matter of regulators not finding out you have a problem – you’re always on top of your own systems.”

Documentation and record keeping were also a must, he said, adding that Geographic Information Systems (GIS) were often used to overlay relief and aerial imagery over topographic imagery. “And then once you’ve got a good snapshot of the terrain, you can set up all your wells that are going to be drilled, your water and gas infrastructure that are going to be laid out. Any amount of data that you want to put on there, it’s a great database system. It can tell you whatever you want to track in the given area. It could be reclamation success, wildlife constraints – whatever is important to your business at that locale.”

In terms of the water chemistry constraints, he said there were three main focus areas with CBM water, with total dissolved solids (TDS) being the first.

“For total dissolved solids it’s a question of how suitable is the water to drink? In the Powder River Basin, for years and years it was not uncommon for people to drill a well into a coal seam and generations lived on drinking coal bed water. Under today’s legislation, it wouldn’t be classified as potable, but TDS is a factor. Electrical conductivity – how sensitive plants react – is also a factor; and the sodium absorption ratio: the water’s suitability for irrigation.”

He showed pictures of livestock watering depots, where coal seam water was available for livestock. They even had little stairs to prevent small animals from not being able to get out of the water pools.

Szmyd also spoke of the importance of protecting the natural surroundings near a CBM operation.

“Wildlife is a part of doing business,” he said. “In 2005 they found a spotted leopard frog and they knew it was a threatened species. Government regulators asked us to study what was happening with the frog.”

Five years later, he said, the frog species was thriving and showing up in the CBM water basins.

CBM water management, according to Szmyd, was also about relationships with landowners, regulators, and the broader community in a CBM area.