EPA’s Recommendations for Cathodic Protection

The Environmental Protection Agency recognizes the need for marine vessels to be protected from corrosion by using cathodic protection systems. Sacrificial anodes and Impressed Current Cathodic Protection (ICCP) systems are both recognized forms of providing protection from corrosion. The Vessel General Permit for Discharges Incidental to the Normal Operation of Vessels (VGP) effective in December 2013 states that:

“EPA recommends, particularly for new vessels, the use of Impressed Current Cathodic Protection (ICCP) in place of or to reduce the use of sacrificial electrodes when technologically feasible (e.g., adequate power sources, appropriate for vessel hull size and design), safe, and adequate to protect against corrosion”. U.S. Environmental Protection Agency [EPA], VGP

Furthermore, the VGP Fact Sheet states that the “EPA believes that ICCP systems are the environmentally preferable method because these systems eliminate or reduce the need for sacrificial anodes”. (EPA, VGP Factsheet) ICCP systems use the vessels own DC electrical current and permanent anodes. Because ICCP systems do not use sacrificial anodes they do not deposit any sacrificial metals into the aquatic environment.

In conjunction with an ICCP system the EPA states that: “If vessel operators use ICCP, they must maintain dielectric shields to prevent flaking” (EPA, VGP). The use of a dielectric shield prevents the anode current shorting to the hull and also allows the current coming from the anode to spread over a larger surface of the hull.

This VGP went into effect on December 19, 2013 and will remain in effect for five years.

Electro-Guard’s ICCP systems will keep your vessel protected while maintaining compliance with EPA recommendations. Our systems are designed to provide safe and adequate protection based on the vessel’s size, hull material and design. Also, our ICCP systems use permanent anodes which reduce the cost to maintain the system and lower the effect on the environment.

Sources

U.S. Environmental Protection Agency (EPA). (2013). U.S. Environmental Protection Agency 2013 Final Issuance of National Pollutant Discharge Elimination System (NPDES) Vessel General Permit (VGP) for Discharges Incidental to the Normal Operation of Vessels Fact Sheet., 4.4.7, p. 122.
http://water.epa.gov/polwaste/npdes/vessels/upload/vgp_fact_sheet2013.pdf

U.S. Environmental Protection Agency (EPA). (2013). Vessel General Permit for Discharges Incidental to the Normal Operation of Vessels (VGP)., 2.2.7, p. 46.
http://water.epa.gov/polwaste/npdes/vessels/upload/vgp_permit2013.pdf