The energy panel organized by undergraduate students at Columbia University here in New York City asked a lot of good questions. The first question was, "What are the potential environmental consequences of fracking? Out of the impacts which are short term and which long term?"
I told them that there are all kinds of worries, but most are not very substantial. Yet, while the potential for environmental impact is small, it is not infinitesimal.
Here is what can happen and what is being done about it:
1. Short term Impact: Well drilling is a construction project: first the surface location is prepared, then the equipment is placed, finally supplies are delivered and the drilling takes place. It takes anywhere from a few weeks to a year or more depending on how many wells are drilled, how deep and long they are. Truck traffic is significant and roads take a beating. To counter this, states like Pennsylvania collect an impact fee. In 2011 that totaled $205 million in 2011. The money is divided between the state, state agencies, counties and municipalities. It is used to repair roads, bridges, provide affordable housing, preserve open space and buy equipment for first responders. Communities that allow drilling must be fairly compensated.
2. Short term Impact: All wells are drilled through aquifers. Nearby water wells may run cloudy for a few days while drilling occurs. That’s from the pressure wave that is created by drilling the surface hole. Typically the disturbance clears up in a few days. If it doesn’t, it’s usually because there is a problem with the water well. In the United States there are millions of rural, unmonitored, unregulated water wells. Many of the wells are old and have never been maintained. Natural gas drilling can expose pre-existing problems with methane and bacteria that the homeowner may not have been aware of. Pre-drilling water samples, and monitoring water while drilling, can be used to improve rural water supplies.
3. Short term Impact: Chemicals and brine handled on the surface may spill. This is not new and companies have procedures to reduce the risk, mitigate the impact, and clean up the spill. All Spills have to be reported to the state authorities. Companies are increasingly using food grade chemicals in their wells. They are self-reported on http://fracfocus.org. By the way, more than 200 energy-producing companies have registered over 15,000 well sites in the past year, not because they had to, but because it was the right thing to do.
4. Long term Impact: Improperly constructed and poorly maintained wells cause problems. They are conduits for gas migration. Surface casing has to be set across the aquifer and cemented into place. This has to be verified with a pressure test and a cement bond log. Intermediate casing must be set across shallow gas zones and cemented into place. This has to be verified with a pressure test and cement bond log. Casing head pressure has to be monitored. If a well develops a casing leak or a tubing leak it has to be repaired.
5. Long term Impact: Poorly sited equipment causes problems. Compressor stations and condensate tanks located near homes cause complaints about noise and smells. Compressors need enclosures and noise abatement. Tanks need vapor recovery.
6. Long term Impact: Improperly plugged and abandoned wells cause problems. The proper procedure is once the well is past its life, it is pumped full of cement. The valves at the surface are disconnected and hauled off. Producers have to set money aside for P&A (plug and abandon) costs. Abandoned and orphaned wells are a problem in some states because this wasn't done. Texas serves as a model for how to cope with the problem. Despite having drilled over a million wells, the state only has 8,000 orphaned and abandoned wells and aggressively locates and plugs 1,400 wells per year.
Every one of these impacts can be addressed by effective regulation and oversight.
Most of them are already being addressed by good will and self interest.
Till Next Time,
Energy Mom
New York City
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