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Offshore Drilling, Onshore Spilling

In case anyone doubts there is any connection between offshore oil and gas drilling, and risks of spills from onshore oil facilities, the helpful officials at BOEMRE have just made that connection crystal clear. Yesterday, BOEMRE awarded the 9th deepwater drilling permit since the BP / Deepwater Horizon spill to Murphy Oil Corporation to resume work on a well in the Green Canyon area of the Gulf of Mexico.

Over one million gallons of oil spilled from a Murphy Oil storage tank damaged by Hurricane Katrina. Photo source: U.S. Environmental Protection Agency

If the name sounds familiar, it should: in 2005 a Murphy oil storage tank damaged by hurricane Katrina spilled one million gallons of crude oil into a residential neighborhood in Chalmette, Louisiana; the biggest single spill of the 9 million gallons estimated by the US Coast Guard that spilled from storm-damaged facilities onshore and offshore. Some of this oil came from Gulf production; some may have been imported. But it’s clear that offshore producers need to have onshore facilities, and these facilities continue to be just as vulnerable to storm damage now as they were six years ago. And hurricanes are just a fact of life along the Gulf and Atlantic coasts.

Crude oil from failed Murphy Oil storage tank impacted 1,700 homes on Chalmette and Meraux, Louisiana. Photo source: Wikimedia
Folks in Virginia might want to think about that as their politicians lead the charge to expand offshore drilling in US waters.

Hurricane Earl and Virginia Offshore Drilling (Lease Area 220)

What if Virginia had active offshore oil and gas development?

We got the latest wind-history data from NOAA, showing the extent of hurricane-force and tropical-storm-force winds as Hurricane Earl moved along the East Coast today. We overlaid these “wind envelopes” on the proposed drilling area designated Lease Area 220. Here is the result, using a satellite image of the storm taken at 3pm EDT as backdrop:

Most of the drilling area would have experienced hurricane conditions today. The western part, along with the coastal support facilities onshore – pipelines, storage tanks, refineries, etc. – would have faced tropical storm conditions.

Here is the source for the wind history data, current through 11am EDT today. We’ll update this map as more complete wind-history data become available:

Mountaintop Removal Mining, Part 2: Mountains at Risk

SkyTruth, in partnership with Appalachian Voices, documented the impact of mountaintop removal coal mining (MTR) over a 59-county area in Kentucky, West Virginia, Tennessee and Virginia by mapping the extent of mountaintop removal mining over a 30 year period using satellite imagery. The historical record shows a 250% increase in MTR occurring over the last two decades, from 77,000 acres in 1985 to over 272,000 acres in 2005. The size of the individual mines also ballooned, with some now covering 15 square miles. Over 2,700 mountain ridges were destroyed by mining. 

While this impacts an enormous area, how many more ridges and mountaintops are vulnerable to this destructive practice?

Map showing predicted risk of mountaintop removal coal mining for Wise County, Virginia

In order to create a risk map, the variables that correlate with MTR must be identified. Our Chief Scientist, Dr. David Campagna, performed a preliminary investigation to determine the drivers of mining occurrence in Wise County, Virginia. Variables such as coal thickness, overburden, land use type, roads, and hydrography were investigated along with our previous analysis of historical to recent mining activity.

Results indicate that two geologic criteria – coal thickness and overburden – best correlate with mining. Using these two variables, we generated a mining risk map for the county based on analysis of the main coal deposit in the area, the Pond Creek seam (see above). Knowing which ridges are at risk of being mined is the key to developing proactive strategies to limit further destruction, and predicting downstream impacts should mining occur.

Mountaintop Removal Mining, Part 1: Measuring the Extent of Mountaintop Removal in Appalachia

Aerial shot of mountaintop removal mining, Kayford Mountain, WV – Photo courtesy of Ohio Valley Environmental Council and Southwings

SkyTruth, in partnership with Appalachian Voices, documented the impact of mountaintop removal mining for coal over a 59-county area in Kentucky, West Virginia, Tennessee and Virginia. The goal of the project was to map the direct landscape impact — the “footprint” — of mountaintop removal mining (MTR) over a 30-year period, from 1976 to 2005.  The analysis was designed and conducted by our Chief Scientist, geologist and remote-sensing expert Dr. David Campagna.

Map showing total extent of surface mining from 1976 – 2005, color-coded by decade

With this analysis, and some great database and Google Earth work by Appalachian Voices, we can tell you exactly which mountains in Appalachia have been – or are are being -destroyed to power your home or business (thought you might like to know…). The methodology involved several steps. The first step included a land cover classification for each decade that identified all the mining occurrences at that point in time. This digital spectral classification process was accomplished using a Landsat satellite image database totaling eight gigabytes of data. Classification required a two-step process where the spectral signatures of land cover types were identified (vegetation, soil, barren or rock, water, etc) and then, through a decision tree analysis, mined areas are classed.

The next step was to classify these mine areas as “MTR” and “Other Surface Mining.” The definition of MTR, as put forth by the U.S. Office of Surface Mining, Reclamation and Enforcement, guided the development of a reproducible, rules-based method to classify the mines. Using digital elevation data from the U.S. Geological Survey 1:100,000 series, the terrain parameters of ridge top, slope, and valleys were calculated.  MTR mines were identified by calculating the amount of ridge top that comprised the mine’s total area.  Any continuous mined landscape that spanned over 320 acres and removed at least 40 acres of ridge top, or spanned between 40 – 320 acres and contained at least 10 – 40 acres of ridge top, was classified as MTR.  Mined areas that were smaller than 40 acres, or did not meet these conditions, were classified as “Other Surface Mines.” 

This analysis shows a 250% increase in the MTR footprint occurring in the last two decades, from 77,000 acres in 1985 to over 272,000 acres in 2005. The size of mining operations also increased, with some contiguous mined areas reaching over 15 square miles. Over 2,700 ridges were impacted by mining. Summary statistics are shown below:

Mountaintop Removal Mines
Total MTR Area Since 1976 = 445,792 Acres
Largest Contiguous Mined Area = 10,410 Acres
Median Mined Area = 128 Acres
Average Mined Area = 406 Acres
Number of Mines > 1 mile2 = 73 
Number of Ridges Mined = 2,789
Total Acres of Impacted Ridges = 130,655 Acres
Average Ridge Length Mined = 1/2 Mile
Largest Ridge Removed = 504 Acres

 

Historical Analysis (Acres Directly Impacted by Mining)

Offshore Drilling: Spillustrations

SkyTruth is getting barraged by requests from people around the country who want to know what could happen if an incident comparable to the Montara / West Atlas oil spill happened off their coast. In response, we’ve generated a series of illustrations that superimpose the area of oil slicks, as shown on satellite images of the Timor Sea disaster, on various parts of the US including:

These illustrations are not predictive spill models – they don’t take into account local winds, currents, shoreline configuration or bathymetry – but they do accurately portray what a Montara-sized oil slick would look like, as shown on some of the satellite images we’ve been collecting and analyzing for that ongoing event.

Illustration showing hypothetical Montara-sized oil spill off the Virginia coast.

The Montara spill is now in its 45th day, as efforts to drill a relief well continue. Using the oil company’s estimate of 400 barrels per day, over 750 thousand gallons of oil have spilled since the blowout on August 21. Using an alternative estimate of 3,000 barrels per day that is based on the actual published flow rates of nearby oil wells, over 5 and a half million gallons may have been spilled so far.