Electrical – Can two ground rods be bonded via a PVC conduit above ground

I've cleaned up after lightning hits an antenna, and designed spark gaps to protect electronics. The last thing I'd do is install a lightning rod through my basement. That stuff should stay outside, irrespective of NEC 810.21(J). Ground loops are not a serious concern in this particular application.

I'd also consider changing the 8' rod into two 4' rods, which are far easier and safer to drive into the ground.

There is no minimum or maximum distance from a foundation, footing, panel or otherwise.

It is best to keep it as close as possible, but nothing dictates this by code. The main thing you want to avoid is getting it a few feed down then hitting the footing. This is a PIA.

Here are the relevant code sections with regard to spacing. Taken form the 2001 NEC.

III. Grounding Electrode System and Grounding Electrode Conductor

250.50 Grounding Electrode System

All grounding electrodes as described in 250.52(A)(1) through (A)(7) that are present at each building or structure served shall be bonded together to form the grounding electrode system. Where none of these grounding electrodes exist, one or more of the grounding electrodes specified in 250.52(A)(4) through (A)(8) shall be installed and used.

250.53 Grounding Electrode System Installation

(B) Electrode Spacing.

Where more than one of the electrodes of the type specified in 250.52(A)(5) or (A)(7) are used, each electrode of one grounding system (including that used for strike termination devices) shall not be less than 1.83 m (6 ft) from any other electrode of another grounding system. Two or more grounding electrodes that are bonded together shall be considered a single grounding electrode system.

(G) Rod and Pipe Electrodes.

The electrode shall be installed such that at least 2.44 m (8 ft) of length is in contact with the soil. It shall be driven to a depth of not less than 2.44 m (8 ft) except that, where rock bottom is encountered, the electrode shall be driven at an oblique angle not to exceed 45 degrees from the vertical or, where rock bottom is encountered at an angle up to 45 degrees, the electrode shall be permitted to be buried in a trench that is at least 750 mm (30 in.) deep. The upper end of the electrode shall be flush with or below ground level unless the aboveground end and the grounding electrode conductor attachment are protected against physical damage as specified in 250.10.