Its my understanding that it's just a portal to the junction box (accessing the big power lines underground) instead of digging a hole every time they have to work on something and need the power off. The big power lines are still underground, and shouldn't be emitting any more current than overhead power lines in any suburban street with power poles.
My sister recently moved down the south coast She really loved a home in the area of Wollongong and from the bedroom window in the distance you could see major overhead power lines. The bank said "Not interested in financing you there, if we need to sell it, they are a major deterrent and we may not get our money back" She then found a house in an area close to there... no power lines...but the green box on the property line... The bank said "NO ! KEEP LOOKING" for exactly the same reasons.
My concern would be......aside from the obvious..."is it safe" How has this affected the resale value of my home, if it was put in near you in your current home... AND How would it affect my resale value if I buy near one...
Just my thought...................................is it safe???? That I cannot answer. Im sure the power company would tell you it is.