A time series study was conducted to ascertain the effect of barometric pressure on the variability of CH4 and CO2 concentrations in a closed landfill site. An in situ data of methane/carbon dioxide concentrations and environmental parameters were collected by means of an in-borehole gas monitor, the GasClam (Ion Science, UK). Linear regression analysis was used to determine the strength of the correlation between ground-gas concentrations and barometric pressure. The result shows CH4 and CO2 concentrations to be variable with weak negative correlations of 0.2691 and 0.2773, respectively, with barometric pressure over the entire monitoring period. Although the R(2) was slightly improved by considering their concentration over single periods of rising and falling pressure, single periods of rising pressure and single periods of falling pressure, their correlations remained insignificant at 95% confidence level. The result revealed that atmospheric pressure--the acclaimed major control on the variability of ground-gas concentration--is not always so. A case was made for the determination of other possible controls such as changes in temperature, soil permeability, landfill water depth, season, and geology of the borehole and also how much of control each factor would have on the variability/migration of CH4 and CO2 concentrations from the studied landfill.

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This study focused on the use of Expanded Polystyrene as an artificial media for the removal of iron from raw water. The experimental set-up consisted of continuous flow process and the mechanism for iron removal was by adsorption. Water sample of initial concentration 5.5mg/l was stored in a 50l container situated at an elevation of 4.4m above the floor and was connected to a plastic transparent container which contained the filter media" Polystyrene". The effects of adsorbent dosage, contact time, pH and temperature were studied. Results showed that adsorption capacity increased with time for the time range of 0.68-47.6mins investigated and slightly with an increase in temperature until 40 o C when it began to decrease, suggesting favorable adsorption at medium temperatures. The results showed that the procedure was efficient in reducing iron concentration from 5.5mg/l to 3.5mg/l within contact time of 5minutes. Better efficiencies could be achieved at higher contact times. The use of EPS material would also offer an avenue for recycling polystyrene widely used in packaging of equipment.

In this study, the background radiation of ten selected mobile phone base stations was monitored to ascertain their radiological risk. The requirement to monitor them is because they are established contributors to background radiation. There is, therefore, often a requirement to monitor them to ascertain if their radiation levels have passed the safety standards. The study was carried out using the Radalert 100 radiation monitor and a Geographical Positioning System (Garmin GPSMAP 765). The mean background radiation exposure rate ranges from 0.0133mRhr-1to 0.0200mRhr-1. The obtained values are higher than the world standard limit of 0.013mRhr-1 recommended by ICRP. The calculated absorbed dose rates for the various base stations ranged from 115.71 nGh-1 to 174.00 nGyh-1. These values of absorbed dose rates were observed to be far higher than the world permissible value of 89 nGyh-1. The annual effective dose equivalent (AEDE) for the exposure values ranged from 0.142 mSvy-1 to 0.213 mSvy-1 which are far lower than the ICRP permissible limits of 1.00 mSvlyr for the public and implies that the base stations do not pose any immediate radiological risks. The excess lifetime cancer risk for the stations' users was all above the 0.29 × 10-3 world recommended value and therefore, suggests a possibility of the base station workers developing radiation-related illnesses over a longer time. Regular radiological monitoring of all the base stations in Ebonyi State is recommended.