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Permalink Reply by dbob on October 25, 2012 at 17:36

Kent/Mrs.  

The are a number of events reported for Oneok (parent company).  I can't tell from the national response center data which are associated with the Sterling line and which are not.  Most do not seem problematic to me - i.e. they are reporting a flaring event in one of their facilities.  

The sterling line should be carrying various NGLs, including the E/P mixture previously noted.  In the event of a leak, once the line is shut in, any residual material will evaporate.  it may temporarily cool and sterilize the soil in the immediate vicinity of the leak, but there should not be any residue.  you could probably replant within days, or the next suitable season. 

"safe" is somewhat subjective - I live near train tracks - 1 mile away from an east/west main line.  In the highly unlikely event of a derailment, and the worst case fire /explosion, me and my neighborhood could be affected.  There is a DOT guidebook that is used in emergency response - look up DOTguidebook or get it here: http://phmsa.dot.gov/staticfiles/PHMSA/DownloadableFiles/Files/Hazm...

you can look up the type of material in the guidebook and see the recommended evacuation radius.  For this type of pipeline, that radius will be based on the fire/explosion hazard.  Outside of that is "safe".  That said, the worst case almost never happens. http://www.texas-fire.com/2009/02/gas-pipeline-explosion-near-carth... This was a really big natural gas line that went up adjacent to a major federal highway and near a gas processing plant.  The damage was limited to a few vehicles, a mobile home, and a few pieces of equipment on the site.  It also melted the highway. 

I wouldn't want it within 50 yards of my home, but would feel fairly safe with it at 200 yards.  I would have concerns if my house was down in a bowl or basin and the pipeline uphill from the house.  

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Permalink Reply by dbob on October 26, 2012 at 16:17

I forgot to ask - do you know if the line will be transporting odorized NGLs or non-odorized NGL? By way of explanation, most propane and natural gas delivered to residential and commercial customers has mercaptan or another odorant added so that you can smell the gas. The gases themselves are generally not directly toxic, but are rather an asphyxant, that can result in insufficient oxygen. In terms of NGLs, if they are odorized, you'll smell them long before they are asphyxiation hazard. The fire/explosion hazard occurs at a much lower concentration - basically if its odorized and you can smell it, its probably a fire/explosion hazard, and you would want to get away. If it isn't odorized and you are concerned, there are fairly simple explosive gas detectors that one could purchase.

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