Sustainable Cement Utilization
[Enugu, Enugu State Nigeria]

2.7.6 Cost Analysis

Cost is the basic and starting point of mass housing provision based on bricks; in carrying out cost comparison, it should not be based on the production cost per brick. Utilization cost for comparative purposes should include handling charges, cost of transport. It has been shown that the use of laterite bricks for walling will result in savings of 30 to 47% and a price index range of 0.53-0.69 per square meter of wall depending on the location of laterite when compared with the use of 450 x 230 x 230 sandcrete blocks. This range is slightly less than the value of 55% reported by [16] that can be attributed to increase in the price of cement from N55 in 1989 to N1,500 in 2007 per 50kg bag. The use of fired clay bricks, which is the most popular alternative walling material in Makurdi metropolis, gave a savings in cost of 19% and a price index of 0.81 when compared with 450×230×230 sandcrete blocks. Based on this analysis, bricks made from laterite and cement is being recommended for building construction in Makurdi and other locations where laterite is readily available (Agbede 2002).

The findings revealed following;

1. Particle size distribution curve of the laterite used in this study was poorly graded and addition of 45% sand corrected this deficiency. Since NBRRI did not specify any particle distribution curve for soil to be used in brick production, addition of 45% sand could serve as a guide for the production of bricks in Makurdi metropolis.

2. Ikpayongo laterite cannot be stabilized effectively for brick production within the economic cement content of 5% as the 28-day UCS of 1.1 N/mm2 did not meet the value recommended by NBRRI (Madedor, 1992).

3. Addition of 45% sand content by dry weight of Ikpayongo laterite enhanced its suitability for use in the production of bricks within the optimum cement content of 5% as the 28 day UCS of 1.8 N/mm2 for bricks made with a soil-sand-cement mixture of 45% sand + 5% cement met the value specified by NBRRI (Madedor, 1992).

4. Cost analysis of available walling materials in Makurdi metropolis has shown that the use of fired clay bricks for building is not as economical as it is generally believed. The use of laterite bricks offers more savings.

5. In order to provide housing for the greater majority of Nigerians the use of laterite bricks should be encouraged as it is cheaper, more readily available and the production process is environmental friendly.

2.8 EFFECT OF CEMENT PRODUCTION ON THE ENVIRONMENT

Cement Produciton Externalities (environmental pollution) and Profitability of Crop This is taken from the activities of the West African Portland Cement Company (WAPCO) PLC in its two plants at Sagamu and Ewekoro on the profitability of Agricultural production in its areas of operation. To this end, study area is divided into two areas- those affected by the operation of the factories, and those not affected (control) (Tijani 2005). Farmers were selected from each area for interview by means of a probabilistic sampling technique. Information was collected by means of a pre-tested structured lxxvi questionnaire from both sets of respondents. Costs and returns were estimated for farmers located in each area; then the probability of farm enterprises as well as the efficiency of resource utilization in the affected area was compared with those in the control area.

The study shows that

(i) the main environmental pollutants generated by the company are dust and noise; thus the inhabitants suffer from air-laden air, cracking of walls of structures as well as soil and water polluted by dust;
(ii) farming was more profitable in the control than in the affected area in both zones: For example, the estimated net returns accruing to an average farmer in the affected area was #190,524.25 per hectare while that in the control area was #272,282.20 per hectare;
(iii) resource productivity was higher in the control area than in the affected area. For example, farmers in the control area earned N4.72 for every N1.00 expended on labour while their counterparts in the affected area earned N2.18; and
(iv) farmers in the affected area incurred additional costs in purifying their water for drinking, attending to their health problems resulting from the activities of the company and effecting repairs on their cracked buildings. The estimated average cost incurred was N24, 000 per annum. These findings imply that the operations of the company have negative effects on the profitability of farm production as well as the productivity of agricultural resources in the lxxvii areas affected by its production activities. Hence, the study suggests that the relevant government agency, Federal Environmental Protection Agency (FEPA), should

(i) Ensure that the company compensates the affected farmers for the damages suffered and
(ii) review the maximum permissible dust and noise emission levels in order to reduce the adverse effects of cement production in the study area.

There are seven cement producing companies in Nigeria operating eight works. The West African Portland Cement Company is currently the leader in the industry; its two operating factories with combined installed capacity of 1.6 million tonnes of cement per annum. The two factories are at Ewekoro (located at kilometer 64 on Lagos – Abeokuta road) and at Shagamu on the outskirts of Shagamu town on the old Ibadan- Lagos road These two cement factories which are surrounded by both residential areas and farm holdings are selected for this study because of the complaints from the residents and farmers of the deleterious effect of cement dust on their health, buildings and their means of livelihood. Hence, there is the need to investigate how beneficial or otherwise is the existence of these factories to the majority of the inhabitants in the immediate localities. This is an issue in environmental economics. Environmental economics is in its infancy in Nigeria probably because our economy is still regarded as principally agricultural in nature. Even in the petroleum industry where environmental pollution is so glaring, emphasis has been on non-economic issues, hence the political agitation for huge compensations and rehabilitation/ amelioration of oil producing environments. Serious in-depth economic studies need to be undertaken in respect of environment degrading activities in oil prospecting, manufacturing and even agricultural ventures so that the nation will be well informed about what policy measures to take to achieve reasonable balance between economic growth and development on the one hand and permissible environmental degradation on the other.

2.8.2 CEMENT PRODUCITON EXTERNALITIES AND PROFITABILITY OF CROP ENTERPRISES

These are the real costs of

(i) poorer quality of soil,
(ii) deposition of cement dust on plant leaves (which lowers their level of photosynthetic activities),
(iii) pollution of water and air by dust
(iv) mandays lost due to health problems and
(v) weakening of foundations, cracking of walls and eventual collapse of buildings arising from continuous blasting of limestone (Tijani 2005).

The earnings per N 1 expenditure on labour in the target area is 2.23 as opposed to 4.72 recorded in the control area. For every N 1 expended on crop production N 1.73 and N 2.18 are realized in the target and control areas respectively. Also, the net income per N 1 expenditure on crop production is N 0.73 and N 1.18 in the two respective area (Table 2). The estimated net return to management, capital and labour in the target area was N166, 479.55 per hectare which is considerably lower than N272,282.20 obtained in the control area.

This is not unexpected as the externalities generated by the production activities of WAPCO is expected to

(i) Impose additional costs on the affected farmers to avert these externalities. This is estimated to be N24, 044.70 (per farmer) per annum in the polluted area.

(ii) Engender loss of labour, which may be total or a partial through sickness of a farmer or that member of his family nursing him (iii) Reduce time allocated to farm operations (by affected farmers) because of travel time to collect and prepare herbs ( for traditional medication) or visit clinics to cure cement dust-related illnesses

(iv) Increase farm production risk- when dust pollution affects the health of household members it increases perturbations in available labour resource which in turn introduces some degree of uncertainty into farm production efforts.

It was found out that the external economies or diseconomies (if any) on agriculture in Shagamu and Ewekoro resulting from the activities of WAPCO’s two cement works in the two towns. The immediate environs of Shagamu and Ewekoro were chosen as the target area while some towns and villages a little distance away were taken as control area for this study. Simple random sampling procedure used to select respondents in both areas for interview. Descriptive statistics and budgetary methods were used to analyze the data collected. The major findings are as follows: (i) The majority of farmers in the polluted area are within 51-60 age bracket while the modal age bracket of those in the control area is 41-50 years. This implies that the most productive age group was not involved in farm production in the affected area due probably to alternative wage employment provided by WAPCO and other companies situated in Shagamu and Ewekoro.

(ii) Farm production risk seems higher in the affected than in the control area as soils in the affected area could only support cassava production in most cases.

(iii) The cost of crop production per hectare (N 252,450.00) was higher in the affected area than that (N235, 705.00) in the control area.

(iv) The estimated cost incurred in eliminating the externalities associated with cement pollution by an average farmer in the affected area was N24, 044.70 per annum.

(v) Farmers in the affected area recorded comparatively lower crop outputs per hectare and hence lower earnings than their counterparts in the control area.

(vi) Farm production was more profitable in the control than in affected area. The net farm income per hectare in the control area was N 272,282.20. as opposed to N190,524.24 in the affected area.

(vii) Earnings of labour per hectare per N1 expenditure was 4.72 in the control area while it was only 2.23 in the affected area. In other words, labour contributes more to the value of output in the control than in the affected area.

The results of this study suggest that the production activities of West African Portland Cement Company have demonstrably negative effects on agricultural production in the area of study. The study therefore suggests that

(i) the permissible dust emission level should be reviewed by Nigeria’s policy makers so that, in the long run, the adverse effects of cement dust pollution on agricultural production will be reduced in the study area