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This paper examines how Jordanian volcanic tuff aggregates affect the characteristics of cement mortar. Five mortar mixes were prepared by replacing normal aggregate (standard sand) with volcanic tuff aggregate in ratios of 0, 25, 50, 75, and 100% (M1 to M5, respectively). Compressive strength, flexural strength, and unit weight were tested at mortar ages of 3, 7, 28, and 56 days. The results revealed improved compressive and flexural strength, which were maximal for the M3 sample. Unit weight decreased as the ratio of volcanic tuff increased. Based on these results, adding Jordanian volcanic tuff in the appropriate ratio will improve these mortar characteristics.

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Reuse of grey water is an attractive option when available water supplies are limited, and can reduce demand on water supplies and provide additional water resource. This comparative research was conducted to assess the suitability and effects of reusing grey water, treated and untreated, as irrigation water for vegetables, compared with tap water. Tomato (Lycopersicon esculentum) and green bean (Phaseolus vulgaris) plants were selected as examples. The collected grey water samples were treated through simple filtration processes using natural volcanic tuff, sand, and zeolite as filtration media. Initial characteristics and the efficiency of treatment in terms of physical, chemical, and biological parameters were determined and high removal efficiency was obtained for COD (82%-87.4%), PO4 -(85%-100%), NO3 -(75%-64%), and Turbidity (58%-89%). Raw grey water, treated grey water, and tap water were used as irrigation water for tomato and green bean plants under a controlled temperature and humidity environment. Growth patterns and rates, and soil properties for each plant were monitored at assigned time intervals. The results indicated better fruit yields, biological yields, and circumference of green beans plants irrigated with tap and treated grey water than untreated grey water. Except number of leaves no significant difference was found in any measurement for tomato plants. In conclusion, the effects of reusing grey water for irrigation depend on the type of plant irrigated and the quality of treatment. The results also suggest that long-term application of grey water can lead to increased soil alkalinity and salinity.

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since the method is usually most effective for sandy subsurface conditions. Although some application sites have The successful application of bioventing systems for in situ remediaincluded clay lenses, only in exceptional cases has biotion of petroleum hydrocarbon-contaminated sites depends on many factors including: moisture content, temperature, number and location venting been applied to sites with extensive overburden of injection and extraction wells, as well as corresponding airflow rates. clay or fractured bedrock (Grasso, 1993). The importance of well locations and air flow rates has been exploredGas permeability is probably the most important site in this study and their optimal values were obtained via the fixed well characteristic. Soils must be sufficiently permeable to method. The design problem was formulated to maximize total conmovement of enough gas to provide adequate oxygen for taminant mass removal within a given time frame subject to physical biodegradation (Barr, 1993). When permeability falls beand budgetary constraints. The technique developed herein was aplow 0.1 Darcy, bioventing applicability is not expected plied to a field case study. Results indicate that optimal well locations to be very effective (Grasso, 1993;Barr, 1993; are found along the mass centerline(s) of the contaminant plume. Rathfelder et al., 1995). Furthermore, well location optimization was proven to be more impor-Factors affecting bioventing can be classified into two tant than pumping rate optimization.

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