Hawai'i Ground Conductivity

[Lopaka]

There was a discussion on another page about AM ground conductivity in the Chicago area, I was wondering if anybody might know how ground conductivity is in Hawai'i.  I would venture that its not real good, but with sea water conductivity that might not be a problem.  Information appreciated, thanks.

[Nostalgia]

Lopaka,
Since nobody weighed in on this here is what I know:  in terms of numbers used by the FCC, the M3 map does not include Hawaii but a supplimental data file m3hw.seq shows ground conductivity at either 2.0 or 5000 millimhos (or millisiemens) per meter, with 5000 obviously being salt water paths and the lower figure is NOT!  Interestingly, there was no in-between, just 2.0 and 5000.  Range across the continental US is .5 to 30.

Remember ground radials are buried just a few inches below the surface so they are not interacting with the water table, let alone the salt water table unless they are right at the oceans edge like the old KKUA 690 tower by Kewalo Basin.  I know I am dating myself but that is what it was when I worked there.  Ground radials and railroad tracks driven into the seabed there was the closest anyone could get to the magic 5000.  The old KUMU tower at the end of Hart St was always having radials pop up through the pavement but they also had a fair number terminating in the canal that ran by the tower but that was brackish water.