Structural failure is one of the concerns of earth scientists in the in the recent time. Most of the
building engineers neglect investigation into the subsurface structure prior to construction
without taking into cognizance the soil type and its variation which is one of the contributing
factors to frequent building collapse in this era. Integrated geophysical methods involving
ground magnetic, Very Low Frequency-Electromagnetic (VLF-EM) and Vertical Electrical
Sounding (VES) were adopted with a view to investigating into the integrity of a reclaimed open
dumpsite in Oyo for civil engineering worthiness. Three (3) traverses were occupied for ground
magnetic and VLF-EM survey. A total length of 100 m was occupied in each traverse along E-W
orientation with inter-station spacing of 10 m. Six (6) VES stations were occupied along two
geoelectric profiles in the study area. The ground magnetic study showed magnetic highs and
lows both on the profiles and the generated 2-D map. The magnetic highs are competent zones
for civil engineering construction while magnetic lows are incompetent zones. The VLF result
revealed conductive and non-conductive zones. More than half of the area of study is
characterized with conductive signatures. Conductive zones are regarded as the incompetent
zones while the non-conductive zones are regarded as competent zones. The VES result showed
that the five out of six VES points occupied are underlain with fractured bedrock while only VES
3 showed fresh bedrock. It is concluded that the study area unsuitable for the construction of
giant structure
