ASSESSMENT OF ENVIRONMENTAL POLICY AND PRACTICES IN SELECTED QUARRIES IN EDO STATE, NIGERIA

Abstract

In this study, eleven soil samples were collected from a depth of 0 – 50 cm in accordance with standard methods of American Standard for Test and Material (ASTM) D6907 and grab sampling method were used to collect fourteen water samples in accordance with American Public Health Association (APHA) standards. The concentration of heavy metal in soil and water sample were determined in accordance with ASTM2010 standards while that of water sample was determined in accordance with ASTM D1976 standard using Atomic Absorption Spectrophotometer (AAS). Accelerometer was used to monitor ground vibrations from blasting. The data obtained were imported into the Slam Stick X Mede software to determine the Peak Particle Velocity (PPV) for sixteen blasts. The level of correlation between, distance of shot from accelerometer, peak particle velocity (PPV) and mass of explosive per shot was performed, the result of the three correlation are -0.748described as high negative correlation, 0.778 described as high positive correlation and 0.293, described as little positive correlation respectively. Five quarries were selected and questionnaire composed of eight sections made up of a total of seventy-five questions that pertains to the health, safety and environment was administered. Mathematical model of Quarry Audit Rating (QAR) was developed, questionnaire was used to investigate and assess the level of environmental compliance of quarry operations. Health, safety and environmental (HSE) Strength Weakness Opportunity and Threat (SWOT) analysis was generated to determine quarry SWOT. The results of heavy metals in the fourteen water samples all have As, Pb, Cd and Cr in levels that exceeds the minimum requirement for potable water as recommended by World Health Organization (WHO) and Standard Organization of Nigeria (SON). Sample AW3, CW2 and DW3 are the most contaminated samples, having eight parameters greater than WHO and SON potable water standard. The most contaminated soil, samples are AS2, BS2, DS2 and ES3, with five parameters greater than world mean heavy metal concentration, while the least contaminated were soil samples CS2 and ES2 contaminated with Hg and Ni, respectively. The result of the AAS for test for the presence of heavy metal in water indicated that from the fourteen samples of water analyzed, 62.857% parameters for heavy metals was higher that both WHO and SON, recommendation for potable water. The results from blast revealed that 43.70 % of the PPV initiated by the blast exceeded the maximum acceptable threshold of 50 mm/s recommended by the International Organization for Standard (ISO). The results established that an average QAR of 74.211% was obtained for the five quarries studied, which is an indication of very strong compliance to extant operational standards. The eight operational tasks investigated via the administered questionnaires showed that the highest compliance was observed in the Quarry Explosives Storage (QES) with a rating of 96.296%, the Quarry Emergency Plans (QEP) with a rating of 57.083% was the lowest, described as partial compliance. The SWOT analysis showed that site A (RCC) and site B (Georgio Rock) have better strength and opportunity of investment and profit margin prospect.