Plum, Pa explosion

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shortbus

Joined Sep 30, 2009
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No one seems to know about it here I guess, it hasn't made the national news. I can't believe that this was caused by a faulty water heater like some of the Pittsburgh TV channels are saying. What do you guys think?

A drone picture of the scene. There were 3 houses before hand. It also blew windows and siding out on houses in the vicinity. I wasn't able to copy and paste the photo here.
https://www.wpxi.com/news/photos-house-leveled/HESZ7XIJLBCLFI5YHRVDSFCD4M/

A door bell video of the explosion -

 

BobTPH

Joined Jun 5, 2013
11,466
It’s a gas explosion. Certainly a defective gas water heater that leaked gas and ignited it could be the culprit.
 

nsaspook

Joined Aug 27, 2009
16,257
No one seems to know about it here I guess, it hasn't made the national news. I can't believe that this was caused by a faulty water heater like some of the Pittsburgh TV channels are saying. What do you guys think?

A drone picture of the scene. There were 3 houses before hand. It also blew windows and siding out on houses in the vicinity. I wasn't able to copy and paste the photo here.
https://www.wpxi.com/news/photos-house-leveled/HESZ7XIJLBCLFI5YHRVDSFCD4M/

A door bell video of the explosion -

I saw it but it's a sad story so I let it slide off my radar.
 

SamR

Joined Mar 19, 2019
5,472
The flames indicate a gas explosion. Steam explosions are also pretty bad which is why all water heaters have a pressure relief valve. People/idiots have been known to wire them down so they won't open but the explosion is a huge white cloud without flames.
 

WBahn

Joined Mar 31, 2012
32,710
I saw it a day or two ago on national news, so it DID make the national news.

The first thing that caught my attention, based on the drone footage in the coverage I saw (which was completely different than in the linked video) was the way that the basement was completely cleaned out with almost no debris in it. That would seem to indicate that that's where the explosion occurred. If it had happened upstairs, I would expect a lot of debris to have been blown downward into the basement.
 

dl324

Joined Mar 30, 2015
18,222
No one seems to know about it here I guess, it hasn't made the national news. I can't believe that this was caused by a faulty water heater like some of the Pittsburgh TV channels are saying. What do you guys think?
Leading theory is uncapped oil and gas wells. PA has over 300,000 of them dating to the 1800's and the governor has a program to begin capping them. They've done 70 and expect to do another 30 by Labor Day. A drop in the bucket, but at least they recognize the problem and are doing something about it.
 

dl324

Joined Mar 30, 2015
18,222
Another datapoint is that 5 million people in that region (more than just PA) live within half a mile of an abandoned well.

NBC reporter had an expert who measured contamination in a stream. It was okay upstream from a methane leak and had 2x the EPA allowance for arsenic downstream.
 

Thread Starter

shortbus

Joined Sep 30, 2009
10,050
I just can't believe that the amount of gas needed to make that big of a fireball and do that much destruction would not have the people involved calling the gas company. That amount of gas surely couldn't support life, could it? This morning one of the news media said all of the first 5 that were killed were in that basement. A sixth person has now died from his injuries.
 

cmartinez

Joined Jan 17, 2007
8,727
I just can't believe that the amount of gas needed to make that big of a fireball and do that much destruction would not have the people involved calling the gas company. That amount of gas surely couldn't support life, could it? This morning one of the news media said all of the first 5 that were killed were in that basement. A sixth person has now died from his injuries.
If the gas had been seeping through the ground (from the mentioned abandoned well, and not from the gas line) then the explosion would've left a crater where the basement was, which doesn't seem to be the case.
 

Thread Starter

shortbus

Joined Sep 30, 2009
10,050
If the gas had been seeping through the ground (from the mentioned abandoned well, and not from the gas line) then the explosion would've left a crater where the basement was, which doesn't seem to be the case.
While there are abandoned wells in that county, one report said there aren't any even close ( miles away if I remember correctly) to that housing development.
 

dl324

Joined Mar 30, 2015
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While there are abandoned wells in that county, one report said there aren't any even close ( miles away if I remember correctly) to that housing development.
NBC reported 5M people in that area living within half a mile of an abandoned well. Depending on geography and winds, gas can collect in areas and explode if an ignition source is present. Maybe the people involved live in stinky areas and they just accepted the smell without recognizing the threat.
 

cmartinez

Joined Jan 17, 2007
8,727
The stinky smell of natural gas is added by the utility for safety. Gas leaking from an abandoned well would not have it.
You're right. The odor added to natural gas comes from a substance called mercaptane, and its similar to the way asparagus smell when they go bad.
 

Thread Starter

shortbus

Joined Sep 30, 2009
10,050
The stinky smell of natural gas is added by the utility for safety. Gas leaking from an abandoned well would not have it.
I have two gas wells on my property, while that gas doesn't have the mercaptan smell it isn't odorless right from the well head. It has oily greasy smell, similar to 90wt rear end oil and you know its gas.
 

WBahn

Joined Mar 31, 2012
32,710
I just can't believe that the amount of gas needed to make that big of a fireball and do that much destruction would not have the people involved calling the gas company. That amount of gas surely couldn't support life, could it? This morning one of the news media said all of the first 5 that were killed were in that basement. A sixth person has now died from his injuries.
The explosive limit of methane (which is what natural gas is mostly composed of) extends from about 4% to about 16%, so at the lower end of that limit it would likely not cause any noticeable issues unless it is carrying something that has a noticeable odor -- and that then requires that the odor be recognizable as something that needs to be dealt with AND that it isn't something that the human sense of smell will simply adapt to and ignore as it builds up slowly.

I haven't seen anywhere that they were all in the basement. That's news to me and causes me to raise my eyebrows. There may be a perfectly innocent explanation for it, but it seems odd for everyone in a household to be down in the basement at 10am on a weekday (was school in session and, if so, why wasn't the 12 year old in school)? Again, I can come up with several completely innocent explanations, but I imagine they are looking into establishing that.
 
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WBahn

Joined Mar 31, 2012
32,710
If the gas had been seeping through the ground (from the mentioned abandoned well, and not from the gas line) then the explosion would've left a crater where the basement was, which doesn't seem to be the case.
Probably not. To explode under the basement, it would have to have had sufficient oxygen handy, plus be present in sufficient quantity. But as it seeps into the basement through all manner of entry avenues, it can accumulate (despite being lighter than air) and has ready access to oxygen. But it IS lighter than air, so the tendency is going to be for it to vent as quickly as it enters -- few basements are going to be sealed tight enough to let it accumulate to explosive levels from ground infiltration. This is why there was never much danger from old-fashioned pilot lights that went out and kept venting gas continuously. I don't know how many of those are still around, since I think it is now required (or at least standard practice) to use a thermocouple in the flame that will shut off the gas supply shortly after the flame goes out). This is often indicated on the appliance by having a "pilot" position on the valve that has to be turned to manually (and is spring loaded to return to the normal ON position when released) that must be held in order to force the valve open and let you light the pilot and then you hold it long enough for the thermocouple to get hot enough to hold the valve open.
 

WBahn

Joined Mar 31, 2012
32,710
NBC reported 5M people in that area living within half a mile of an abandoned well. Depending on geography and winds, gas can collect in areas and explode if an ignition source is present. Maybe the people involved live in stinky areas and they just accepted the smell without recognizing the threat.
I'm skeptical because it seems odd that with enough natural gas moving around to get it to collect in a basement to the point of exploding like that, that this was the ONLY house that had a problem. Surely there are numerous other houses with basements and ignition sources in the area along the intrusion route.

My initial bet is either on a cracked gas line or a malfunctioning appliance, probably the furnace or hot water heater.
 

dl324

Joined Mar 30, 2015
18,222
My initial bet is either on a cracked gas line or a malfunctioning appliance, probably the furnace or hot water heater.
That would affect multiple houses? The last explosion might have been a single house, but I heard on the news about an instance where 5 houses were involved.

What I know is based on reporters contacting experts in the area who have more insight into the problem. The info on the number of capped wells came directly from the governor of the state.
 

strantor

Joined Oct 3, 2010
6,875
I thought when a house explodes, it was a meth lab until proven otherwise in a court of public opinion. But maybe that's regional.
 
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