GEOTECHNICAL ASSESSMENT OF SUBSOIL CORROSIVITY ALONG PIPIELINE ROIUTE IN OYIGBO LOCAL GOVERNMENT AREA, RIVERS STATE, NIGERIA

Abstract

Geotechnical assessment of subsoil corrosivity along pipeline route in Oyigbo Local Government Area
in Rivers State of Nigeria was carried out using SRMPCS model an acronym for Soil type, Resistivity,
Moisture content, Hydrogen concentration (pH), Chloride and Sulphate. The study area is located in
Oyibo area of Rivers state, Niger Delta, Nigeria which lies between longitude 7777 and 6666 m
(Eastings), and latitude 5555 and 44444 m (Northings) based on Universal Traverse Mercator System
(WGS84) and the length extent is about 15km long. The surface geology/deposits in this area
comprises fine to medium silty sandy clay, brownish in color. A total of ten (10) vertical electrical
sounding (VES) was acquired from the study area based on Wenner four pin electrode configuration
with maximum electrode spacing of 60 m. The TERCA 3 Earth Resistivity Tester (CHAUVIN ARNOUX
–CA6470N) was used to acquirer data along the pipeline routes. Physiochemical properties of samples
of ten (10) location from the study area was acquired based on the SRMPCS model. The presented
SRMPCS model and model map revealed that the corrosion zones are divided into two categories that
is “Very mildly corrosive and mildly corrosive. The results obtained from this study indicated that most
of the soil environment is mildly corrosive in nature.