Figure 2. Mild steel coupon: a – new, unexposed coupon, b – coupon retrieved from the water-logged soil site, c – coupon after cleaning

From

Effect of Tetrakis (Hydroxymethyl) Phosphonium Sulphate Biocide on Metal Loss in Mild Steel Coupons Buried in a Water-logged Soil

Kingsley O. Oparaodu, Gideon C. Okpokwasili

Journal of Applied & Environmental Microbiology. 2014, 2(5), 253-256 doi:10.12691/jaem-2-5-9