Anchor Guard: Understanding and Preventing

3. Conditions That Require Corrosion Control Measures

3.1 The following conditions indicate risk of anchor corrosion and therefore require corrosion control measures beyond hot-dip galvanizing (see Section 5).

3.1.1 Corrosion is visible below grade on the anchors in question or other adjacent structures, or underground corrosion has previously been identified as a problem in the area.

3.1.2 A soil sample measured in a saturated state, or a "Wenner four-pin" soil resistivity test at the tower site indicate soil resistivity to be equal to or less than 10,000 ohm/cm.

3.1.3 Tower grounding incorporates more than one copper-clad ground rod at each anchor and more than three at the tower base, or tower is electrically connected to other buried structures, i.e., fencing, buildings, buried tanks, underground power cables, etc.

3.1.4 Tower anchors are subject to "stray current" generated from sources such as adjacent buried pipelines or other cathodically protected structures, welding or plating facilities, electrified railways, HVAC systems or other sources of artificially induced DC ground current.

3.1.5 Tower is located near electrical substation or other highly grounded facility.

3.1.6 Guy anchors are located in water, saturated soil or soil rich in salts.

3.1.7 Tower is located where fertilization of plant life is common.

3.1.8 Soil at the tower site is determined to be corrosive (see Section 2.2).

3.2 Corrosion control measures may be necessary under conditions not listed herein. Consult a corrosion specialist for guidance.