Thursday, May 2, 2013

A Fragmented Divide? Simulating Gas Development in the Thompson Divide


Top: Aerial photo taken October 2012 of the Yank Creek watershed in the Thompson Divide, a wilderness area located in western Colorado. Credit: Jane Pargiter - EcoFlight

Bottom: SkyTruth simulation of the same area of the Thompson Divide overlain with simulated five-acre well pads and new service roads (in white). To see more views of our simulation, click here.

Recently, the Bureau of Land Management (BLM) announced they would temporarily suspend 25 oil and gas leases in the Thompson Divide, a wild swath of backcountry covering 221,500 acres of public land in western Colorado. Because the lease holders did not diligently develop these leases and are running out of time on their ten-year lease terms, they asked BLM for an extension.  While this decision paused the clock on drilling for natural gas in this rugged portion of the White River National Forest, our friends at the Wilderness Workshop and Thompson Divide Coalition, as well as thousands of people from around the country, were pressing for BLM to allow the leases to expire this year. 

The Lake Ridge unit of the Thompson Divide is a high quality backcountry dominated by roadless areas reaching from the Sunlight Ski Area (south of Glenwood Springs) in the north to McClure Pass (between Carrbondale and Paonia) in the south.  It is heavily forested, spans five watersheds, and provides valuable habitat for lynx, mountain lion, bear, moose, native cutthroat trout, and elk. Recreation, grazing, hunting and fishing in the area brings $30 million a year to Colorado's economy.  However, developing gas in this region would require intensive horizontal drilling and hydraulic fracturing (fracking), and new roads would have to be built in roadless areas. 
Looking southwest over our simulation of drilling in the Lake Ridge Unit of Thompson Divide from north of the Sunlight Ski Area. To see more views of our simulation, click here.



Surface disturbance, habitat fragmentation, persistent noise, air and water pollution, heavy truck traffic, and industrial accidents are some of the issues the U.S. Forest Service and BLM will have to consider in their environmental analysis of the impact that drilling will have on this public landTo help visualize what this unconventional gas development could look like in this unfragmented swath of backcountry, we traced out access roads and 132 five-acre well pads onto Google Earth imagery of the Lake Ridge Unit west of Carbondale.

Looking north over the Thompson Divide with Carbondale to the northeast. To see more views of our simulation, click here.
While gas wells, roads, pipelines, compressor stations and other infrastructure would fragment the Thompson Divide, a wide range of stakeholders and citizen groups have joined together out of concern for this valuable resource. Local citizens have united with the goal of preserving the existing value and uses of the Thompson Divide, and we hope our simulation will help put in perspective what the future could look like if the leases are developed when BLM's suspension ends on April 1, 2014. 

Watch the video below to take an aerial tour of Thompson Divide as it looks today.

3 comments:

  1. This comment was originally posted by David Kane but in managing visibility of comments we inadvertently removed this comment. This is part one of the full text of his comment:

    SkyTruth: "promotes environmental awareness and protection with remote sensing and digital mapping technology. We provide stunning images backed by scientifically robust information about our changing environment to stimulate changes in habitat protection, biodiversity conservation, and sustainable resource management. " This is doubtful based on this very weak and extremely rudimentary analysis.

    And what scientific data did you use in this exercise? Doesn't look to me that you used any real data. First, you made the incredibly ridiculous assumption that there would be 132 five-acre well pads? None of the lease holders have proposed anything remotely close to this. There have been no plans of development proposed, so basically you made the data up to suit your own purposes.

    Did you consider that these wells would NOT be developed simultaneously? Most well Pads would be less than 3 acres not five acres, unless of course they are using the larger flex rigs to drill multiple wells (up to 22 or 33) from a single pad, then you might need a five acre well pad. Flex rigs are expensive and because of their size are not conducive to an area such as this. Secondly, if you do use flex rigs, you wouldn't need 132 well pads.. not even close. In fact, there would never be 132 well pads constructed, and definitely simultaneously. Obviously, you are making the assumption that all of the areas of the leases have gas even distributed across the lease. Pretty geologically unlikely, hence the use of directional drilling to test where the pockets of gas are. You didn't account for interim reclamation of well pads, so in effect you would never have well pad after well pad unreclaimed. More than two-thirds of the well pads would be reclaimed.

    Thirdly, you made absolutely no accounting for where you put the well pads on Google Earth. Anybody can put a bunch of dots on a map, and you did just that. One just has to look where you have some of the "pads." Some are literally hanging over steep slopes, others are in drainages. Your roads placement is based on what exactly? Again you're making up data for plans that don't remotely exist.

    Your "simulation" also fails to account for steep slopes (you can't put well pads by regulation on slopes over 25%, for example...you should try using some ArcGIS and DEMs before you willy nilly put a dot on the places you do. You also fail to account for such things as sensitive wildlife habitats, hydrologics, appropriate well-spacing, and the list goes.

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  2. Part II of David Kane's comment:

    Fifth, not a single well pad or access road would be approved without conducting an extensive onsite with BLM and FS staff and the operators. Anybody with an ounce of knowledge knows that some well pads would be lost. Not to fail to mention that the only plan that has been proposed is 7-9 single exploratory wells.

    Sixth, you say that drilling and road access would occur in roadless areas? Designated roadless? If so, not so. The current proposals deliberately avoid the roadless area.

    Seventh, you say this is "unfragmented" landscape. You apparently were unable to see the numerous existing well pads, compressor stations, and access roads already in use by SourceGas, including natural gas storage facilities. A convenient oversight? And you also didn't highlight the existing network of logging roads and existing pipeline corridors.

    Lastly, you make the seeming assumption that though the economic analysis hypothesized that recreation and grazing are worth $30M, that if drilling occurs that this $30M would magically disappear as they are automatically mutually exclusive activities. There's no evidence of that, especially given the current proposal, which again IS NOT a 132 5-acre well pad build out.

    This is not a well-though out analysis by any means. It smacks of an unrealistic dramatization that is not based in an iota of fact or knowledge. It's amateurish at best. There is no "truth" in your analysis.

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  3. SkyTruth's response to David Kane:

    David, our simulation here is based on assumptions which we believe are reasonable. For the drilling density we relied on the guidance of our colleagues at Wilderness Workshop who are more familiar with existing and speculated development of near-by tracts of public lands by the same operators. In the short-term you are correct, only a few permits have been applied for. In the long-term, however, shale gas and coal-bed methane development is by nature very dense, because all developable gas must be reached by the fractures emanating only a few hundred feet from the wellbore; unlike conventional oil and gas which can be extracted by a few strategically placed wells that tap into pockets.

    Compare this to other areas developed in the same way (Such as the Upper Green River Valley of Wyoming - http://www.flickr.com/photos/skytruth/sets/72157625949361693/, and the Marcellus Shale in W. Pennsylvania - http://www.flickr.com/photos/skytruth/sets/72157630822199036/with/7677229894/), and you should see the pattern is consistent with our model. Furthermore, one well pad per 245 acres is quite conservative, given that plays such as the Barnett Shale are being developed as densely as one pad per 40 acres (http://www.marcellus.psu.edu/resources/PDFs/Focusonthemarcellus.pdf) and even closer in places such as the Jonah Field in Wyoming.

    Simultaneous development is not the only scenario where this simulation could become a reality, because interim reclamation remains an unlikely and a so-far unrealized proposition for unconventional drilling. Unconventional wells can be re-fracked, and given the significant drop in production from wells stimulated by modern high-volume slick-water fracking that is starting to be documented, it is likely re-stimulation will be necessary. Frequently revisiting these wells to frack precludes any significant reclamation more than replanting grass. The assumption that the wellpads will be evenly spaced is supported by the local geology since there are no significant pockets to be probed for, only layers of rock to be laterally drilled and fracked. It is true, though, that some areas by have thicker coal beds or shale deposits than others and this is an unknown that we can’t account for now.

    Habitat fragmentation occurs exponentially, so while the economic value of the Thompson Divide is not completely exclusive to its current state, there is tremendous opportunity cost when islands of remote backcountry are diced up smaller and smaller.The general point of this simulation is to provide a rough idea what the land could look like, not a concrete example of where each and every pad and road will go. We hope that this will provide some context for the discussion of the ultimate outcome.

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