b"Estimating Corrosion PotentialThere are a number of variables that influence the 1989; along with data published in the proceedingscorrosionpotentialforundergroundmetallic ofthe EighthInternationalAshUtilizationstructures.MelvinRomanoffhasconducted Symposium,Vol.2,AmericanCoalAshextensive field testing of buried metal structures to Association,Washington,DC,October,1987.evaluate thecorrosionlevelsrelatedtothemore These data were used to develop Graph 3, whichsignificant variables.These results, published by allows during the design process for an empiricalRomanoff in Underground Corrosion, National calculation to estimate losses due to corrosion.BureauofStandardscircular579,HoustonTX, CORROSION POTENTIAL ESTIMATING GRAPHUNDERGROUND BARE STEEL STRUCTURESCORROSION POTENTIAL100,00070,000 UNLIKELY50,000 ALL pH's20,000 3 pH 6 SLIGHT10,0007000 MILD5000) -cm RESISTIVITY (ohmMODERATE20001000 Earth Contact Products700500SEVERE200 pH 4.5pH 12 pH 10.51007050pH = 5 pH = 6 pH = 7 pH = 8 pH = 9 pH = 100 0.25 0.5 0.75 1.0 1.25 1.5 1.75 2.0 2.25 2.5LOSS IN WEIGHT BY CORROSION PER YEAR (oz./sq. ft.)Graph 3.Prediction of steel loss due to corrosion relative to soil resistivity and pH.ECP Technical Design Manual Corrosion Life2021 Earth Contact Products, L.L.C.2021-09 Chapter 8 - Page 150 All rights reserved"