Schon bei der konventionellen Gasförderung gibt es viele Risiken. Diese bleiben auch bei der unkonventionellen Gasförderung erhalten, aber verschärfen sich noch einmal durch den komplizierten Prozess des Hydraulic Fracturings.
Die folgende Liste ist nur ein kleiner Überblick von Unfällen der letzten Jahre in den USA. Mit dabei aber Unternehmen, die in Europa bei der Erdgassuche mit dabei sein wollen.
Die Probleme reichen von unkontrollierten Ausbrüchen während des Frackings, undichter Zementierung, überlaufender und auslaufender Frackwasser-Tanks, Explosionen und Bränden und den dabei entstehenden Schäden für Mensch und Umwelt.
Auch wenn das prozentuale Risiko, dass bei einer Bohrung etwas schief gehen kann gleich bleibt oder sinkt, erhöht sich die Wahrscheinlichkeit für schwere Unfälle mit jeder neuen Bohrung.
5. August 2011
NORTH MAHONING TOWNSHIP, INDIANA COUNTY – Route 119 in North Mahoning Township, Indiana County reopened this morning after an overnight crash.
A tractor trailer carrying an acid used in the fracking process of drilling for marcellus shale gas overturned around midnight.
[...] It was hauling ten containers filled with the fracking liquid; nine of those started leaking, along with diesel fuel. Ten houses in the area were evacuated.
15. Juni 2011
“DEP spokeman Daniel Spadoni said methane has been found in five water wells. Test results show methane levels were elevated in two of the wells while results of the other three are pending.
We initially received a complaint about bubbling in a private drinking water well on May 17, Spadoni said. We did find elevated levels of methane in the head space of that well.
XTO Energy, a division of ExxonMobil, has a well pad with three drilled and hydrofractured natural gas wells on it within about 2,300 feet of that well, according to Spadoni.”
7. Juni 2011
“The cause of the accident was a slick, gel-like, foamy substance that was spilled on the south bound lane of Wallis Run Road for 10 miles. Both DEP and PennDoT assumed the unknown chemical was leaked by a gas industry truck, but the truck had not been found nor the substance positively identified[...]”
“We have not pinpointed the source of the spill nor been able to get a positive identification of the chemical along 10 miles of roadway. Until we have a confirmed lab analysis, and are able to check the MSDS data, we cannot make a statement as to the potential harm or lack thereof that this substance may pose to the environment, to nearby waterways, or to human health.”
22. Mai 2011
ARROW Energy is dealing with a “significant” diesel spill on its Moranbah gasfields site, just days after capping a blown gas well at Dalby. [...] Mr Hinchliffe blasted Arrow for its “tardy” handling of the Dalby incident, which sent methane and water spewing up to 90m high for more than a day.
20. April 2011
In Bradford County (Penssylvania), kam es am 20. April 2011 beim Fracken nach Erdgas zu einem sogenannten Blowout.
Zehntausende Liter Frackflüssigkeit, einem Gemisch aus Wasser, Sand und teils hochgiftigen Chemikalien, wurden dabei in der Umgebung verteilt und flossen auch nach Stunden, trotz des Einsatzes mehrer Notfall-Teams, noch in einen nahe gelegen Bach.
Der explosionsartigen Austritt wurde durch einen nicht näher genannten technischen Fehler verursacht. Betreiber der Anlage ist Chesapeake Energy, das zweitgrößte Unternehmen im Bereich der unkonventionellen Gasförderung in den USA
But when the coupling failed at Atgas 2H, the water simply came gushing too fast for Chesapeake’s operators to bring it under control and collect it. Making matters worse, days of steady rain had partially filled the containment pits and they quickly overflowed, according to preliminary reports. Berms, which are required to be constructed around all of Pennsylvania’s 3- to 5-acre drill pads like Atgas 2H, also failed to stem the flow, allowing the fracking fluid to escape into the environment.
ALLENTOWN, Pa. — Federal environmental officials say that testing has revealed contamination in three private water wells following an April blowout at a Pennsylvania natural gas drilling site.
Environmental Protection Agency spokesman Roy Seneca said today that EPA took water samples from seven private water wells near the Chesapeake Energy Corp. drilling site near Canton in in northeastern Pennsylvania’s Bradford County.
EPA briefed residents on the sampling results Thursday. Seneca declined to reveal the nature of the contamination. He says EPA will sample the wells again in July.
15. März 2011
The meeting was held to discuss concerns over gas migration causing ignition points and resident’s homes exploding. At least two homes in the area have exploded and there have been several injuries. Migrating methane gas is the suspected cause of these explosions and the migration caused by unconventional natural gas drilling in the area.
It’s reasoned that older oil and gas wells from the late 1800s and into the early 1980s which were never plugged or sealed properly could be facilitating this migration. New unconventional gas fracking could be forcing a build up of these methane gases.
1. März 2011
It took her five hours on Tuesday to learn that there had been an explosion in a holding tank at a natural gas well site a half-mile away from her home in Mount Pleasant, Washington County. The result was a controlled fire near a compressor station, which pressurizes natural gas from Marcellus Shale wells in the area of Caldwell Road, west of the village of Hickory.
When the blast occurred, no one was at the station, one of two on the hillside of a former dairy farm. The compressor station is owned by MarkWest Liberty Midstream Resources LLC.
The fire occurred at a complex of three storage tanks about 25 feet high and 8 feet wide at the base roughly 100 yards from the MarkWest compressor station, where natural gas is pressurized and moved along a pipeline to a processing plant.
A mixture of liquid hydrocarbon waste called condensate flows into one of the tanks and then migrates into two other tanks, leaving behind mostly a briny fluid, according to information from Mr. Yates and Dan Campbell, a MarkWest spokesman in Denver.
The tank designed to hold the liquid apparently was empty or nearly empty but still contained vapors. The tank operates like a hot-water heater, Chief Smith said, with a thermostat controlling a heating element designed to prevent the liquid mixture from freezing.
On Tuesday, the liquid mixture that was in the first tank was not high enough to cover the thermostat, at which point it would normally shut off the heating element. But for some reason, the heating element continued to operate, eventually heating the vapors to combustible temperatures, resulting in the explosion.
23. Februar 2011
AVELLA, Pa. — An explosion and fire at a gas well injured three workers Wednesday night in Avella, authorities said.
The blast, at the Chesapeake Appalachia LLC Powers site was reported at about 6:20 p.m., Washington County emergency officials said.
Workers were transferring water used in a gas-extraction process called hydraulic fracturing, and several of the natural gas liquid storage tanks caught fire, said Katy Gresh, a spokeswoman for the Department of Environmental Protection’s southwest region.
11. Februar 2011
A leak in a Benzie County natural gas well this week is likely to refocus attention on Michigan’s natural gas drilling rules, which don’t require companies to disclose the chemicals they use.
30. Januar 2011
The “well control incident,” as the DEP termed it, occurred shortly after noon on Jan. 17 at a Talisman Energy well in Tioga State Forest. The well pad is located in Ward Township, about five miles east of Blossburg.
During the hydraulic fracturing process, fracking fluids and sand were discharged from the well into the air, according to the DEP.
CUDD Well Control, which specializes in handling such emergencies, also responded.No significant amount of natural gas was released and there was no fire or explosion. The fracking fluids were contained within the lined well pad, the DEP said.
The spilled fracking fluids were cleaned up by a contractor and samples were taken to determine if contaminated soil will need to be removed. Samples were also taken from beneath the well pad liner.
22. November 2010
WILLIAMSPORT — The Department of Environmental Protection is continuing to investigate a large hydraulic fracturing fluid spill at an XTO Energy natural gas well pad in Penn Township, Lycoming County, which was first discovered last week.
“This spill was initially estimated at more than 13,000 gallons by the company and has polluted an unnamed tributary to Sugar Run and a spring,” said DEP Northcentral Regional Director Nels Taber. “There are also two private drinking water wells in the vicinity that will be sampled for possible impacts.”
15. November 2010
“A natural gas well blew out Sunday night in Frio County, sending a plumes of water gushing into the air. A hazardous materials crew was monitoring the smelly situation Monday.
Officials are asking residents of a Pearsall mobile home park to voluntarily evacutate the area that sits about a quarter mile from the site.”
Der Blowout geschah durch eine alte – vergessene Bohrung – die durch den Fracking Prozess unabsichtlich geöffnet wurde. Erst nach einer Woche konnte der Ausbruch von Frack-Flüssigkeit und Lagerstättenwasser gestoppt werden.
26. August 2010
Federal environment officials investigating drinking water contamination near the ranching town of Pavillion, Wyo., have found that at least three water wells contain a chemical used in the natural gas drilling process of hydraulic fracturing. Scientists also found traces of other contaminants, including oil, gas or metals, in 11 of 39 wells tested there since March.
23. Juli 2010
“On Friday a two-year-old shallow gas well exploded in Indiana Township (Allegheny County), PA killing two workers. According to sources, multiple parties are involved in the investigation, including the PA Department of Environmental Protection (DEP), Occupational Safety and Health Administration (OSHA), Allegheny County fire marshal and Huntley & Huntley Inc., the Monroeville company that employed the workers.”
7. Juni 2010
MOUNDSVILLE, W.Va. — A state inspector said a crew drilling a gas well through an abandoned coal mine ignited methane, triggering an explosion that burned seven workers in Marshall County early Monday.
The blast created a column of fire that was initially at least 70 feet high, but the flames were down to about 40 feet within hours. Gas continued to burn late in the afternoon.
11. Juni 2010
LAWRENCE TOWNSHIP, Pa. — Pennsylvania regulators said they’re halting all gas drilling activities by the company whose natural gas well spewed out explosive gas and polluted water for 16 hours on Thursday night and Friday morning in Clearfield County.
The operators lost control while they were preparing to extract gas from fractured shale, according to the state Department of Environmental Protection, which said it plans to “aggressively” investigate what may be the Pennsylvania’s worst Marcellus Shale drilling accident ever.
22. September 2009
Last week, three spills of potentially carcinogenic hazardous chemicals at a natural gas drilling site in Pennsylvania prompted the state’s environmental protection agency to suspend Cabot Oil & Gas’s operations in the county.
The spills were just a small part of a larger phenomenon — accidents at natural gas drilling sites that have imperiled the drinking water of nearby communities in states from Pennsylvania to Wyoming and that have no governmental