House in Northern Virginia on right-of-way (ROW) with single-circuit
525 kV and 230 kV transmission lines and adjacent single-circuit 34.5
kV distribution line. The house is only 75 feet from the 34.5 kV line,
100 feet from the 525 kV center conductor and 180 feet from the 230 kV
lines.
The Profile Plot (see below) shows magnetic field data
collected on a warm 89.8 degree (F) day. Levels in the house were 10-15
mG with the peaks of 33.9 mG, 30 mG and 20 mG recorded under the 525
kV, 34.5 kV and 230 kV lines, respectively. It should be noted that during
seasonal peak loads the magnetic field levels could easily double or
triple since the 525 kV is a high current (double-bundle) transmission
line. Therefore, the levels within the house could range under worst-case
conditions from 20-30 mG to 30-45 mG.
Magnetic Field Management Solution:
Install an Active Magnetic Field Cancellation System around
the house to (mitigate) reduce the magnetic field levels inside the house
to less than 2 mG.
