Thursday, February 26, 2015

Deep Well Injection Visual

If you're like me, it's hard to visualize the relative depths and distances involved with deep well injection. These wells, of course, have Stevenson Ranch in an uproar: based on the current proposal, millions of gallons of brine will be injected beneath their community as part of efforts to remove chloride from wastewater. Visualizing might not be absolutely necessary, but it's interesting. So here are two simple figures constructed carefully to scale (sources/calculations below if you want to check my work).

The main takeaway? The new site is only 800 feet north of the former proposed site. If you're worried now, then you probably should have been worried before. Other takeaways? Our feelings about these matters are all a matter of scale.

 
 
 
SOURCES/CALCULATIONS:
Heights & Depths
*Six Flags Sky Tower height = 385 feet
www.thecoasterguy.com/2011/01/07/six-flags-magic-mountain-sky-tower-factoid/

*Hyatt Regency height = 73 feet
www.emporis.com/buildings/338142/hyatt-regency-valencia-santa-clarita-ca-usa

*Two-story house height = 25 feet
approximation

*Minimum deep water well injection depth = 9000 feet
http://www.signalscv.com/section/36/article/133397/
"...injecting it some 9,000 to 13,000 feet under the ground."


Distances
*Six Flags to Hyatt Regency = 10,800 feet
Measured with Google Earth Pro

*Old deep well site to new deep well site at Tournament Players Club = 800 feet
www.lacsd.org/civica/filebank/blobdload.asp?BlobID=9556
"Consequently, the SCVSD proposes to develop an alternate site located approximately 800 feet north of the original location"


Volumes
*Maximum daily disposal = 500,000 gallons of brine, which fills a 40.6' cube
From p. 392 of pdf http://www.lacsd.org/civica/filebank/blobdload.asp?BlobID=9854
"...construct a deep well injection (DWI) facility to dispose of up to 0.5 million gallons per day (mgd) of brine..."
cuberoot(500,000gal * 1ft^3/7.48gal) = 40.6 feet, so a cube of 40.6 feet/side holds 500,000 gal brine

*Maximum yearly disposal = 182,500,000 gallons of brine, which fills a 290.0' cube
From p. 392 of pdf www.lacsd.org/civica/filebank/blobdload.asp?BlobID=9854
"...construct a deep well injection (DWI) facility to dispose of up to 0.5 million gallons per day (mgd) of brine..."
cuberoot(500,000gal/day * 1ft^3/7.48gal * 365 days) = 290.0 feet, so a cube of 290.0 feet/side holds 182,500,000 gal brine

1 comment:

theorivas said...

This is a great chart. Thanks for putting in the effort.