Kinetic and adsorption study of acid dye removal using activated carbon

The adsorption of three acid dyes, Acid Red 97, Acid Orange 61 and Acid Brown 425 onto activated carbon was studied for the removal of acid dyes from aqueous solutions at room temperature (25 degrees C). The adsorption of each dye with respect to contact time was then measured to provide information about the adsorption characteristics of activated carbon. The rates of adsorption were found to conform to the pseudo-second-order kinetics with a good correlation. The experimental isotherms obtained, except for Acid Orange 61 studied in mixture, were of the S-type in terms of the classification of Giles and co-workers. The best fit of the adsorption isotherm data was obtained using the Freundlich model. When a comparative study was made of the results obtained with single and mixed dyes, it can be seen that some of them affect others and modify their behavior in the adsorption process. The results indicate that activated carbon could be employed for the removal of dyes from wastewater.     

The hardrock minerals industry and the landscape architect

The landscape architecture profession is a source of creative thinking and planning which is relatively untapped within the mining industry in the United States of America. The landscape architect has been active in European operations for years as indicated by the four examples presented. The landscape architect can provide an important interface with mine design and engineering and environmental affairs. To initiate this interface within the United States, and increase its effectiveness, six objectives are presented and discussed.     

Chorionic villus sampling utilization following reports of a possible association with fetal limb defects

Prenatal diagnosis choices were reviewed in 473 women who presented for genetic counselling prior to 11 weeks' gestation for the indication of advanced maternal age. Group A consisted of 336 patients who were unaware of a possible association between chorionic villus sampling (CVS) and limb defects. Group B consisted of 137 patients who were provided this information. Fifty-one per cent of patients in group A and 45 per cent of patients in group B chose CVS. This difference was not significant by χ² analysis (P = 0·7). Patterns of prenatal diagnosis procedure utilization from 1987 to 1992 revealed a significant reduction in CVS utilization accompanied by a corresponding increase in amniocentesis after the association between CVS and limb defects was publicized. Referrals for CVS counselling also significantly declined. However, acceptance rates did not change for those patients who received genetic counselling. First-trimester genetic counselling, including a discussion regarding a possible association between CVS and limb defects, helps patients make informed decisions concerning prenatal diagnosis options, and, in our population, resulted in no change in CVS acceptance rates.     

Socio-economic impact management: programme design and implementation considerations

While larger mineral resource development projects offer new jobs and provide a stimulus to the economy of the area where they are sited, they may also pose problems in rural areas associated with rapid population growth. The purpose of an impact management programme is to anticipate and alleviate project effects that are generally perceived as undesirable and to enhance effects that are beneficial to site area communities. While the effective management of project effects is the end towards which all impact assessment efforts are directed, an integrated approach to impact management has been notably lacking. This paper suggests a systems framework for meeting this need by: (1) reviewing the need for impact management efforts; (2) discussing the objectives of, and considerations in, designing impact management programmes; (3) presenting a conceptual framework for, and key components of, such a programme; and (4) suggesting an approach for implementing such a system as an integral part of the project development process.     

White-tailed deer movement and distribution about surface coal mines in West Virginia,USA

Deer movements around surface coal mines were investigated in Preston Country, West Virginia, USA. Seventy-two deer crossings were counted on 29 surface mines with only 8% found on highwalls with more than 20% rock or stone. Thus, although slope was important, the percentage of dirt on the highwall determined use as a crossing location for deer. The average distance between all deer crossing was 209.7 m but the distance between the end of the highwall and the nearest highwall crossing was 248.7 m indicating reluctance of deer to cross mines when they could walk around them. Winter snow track counts showed fewer deer within 90 m of the top edge of the highwall. Four land bridges traversed the highwall and were heavily utilized by deer, especially in March, April, May, October and November. The surface mine bench was used as a fawn bedding area, but little feeding occurred on this portion of the mine.     

A field test of processed oil shale reclamation strategies designed for minimal use of limited resources

Reclamation of processed oil shale disposal areas in the arid and semi-arid regions of Utah, Colorado and Wyoming faces several challenging problems. Shallow topsoil, harsh climate and limited water supply and low suitability of processed oil shale as a plant growth medium must be addressed if any reclamation plan is to be successful.A prototype reclamation plan that addressed the harsh environmental conditions was proposed early in the development of oil shale in eastern Utah. Studies to validate the reclamation plan were initiated in 1978 on a simulated oil shale disposal area at Anvil Points, Colorado.Four native shrubs, one forb and a grass, were successfully established by planting container-grown transplants into a topsoil-filled V-shaped trench. Supplemental water was provided from an adjacent water harvesting slope. The roots of the transplanted species grew into the adjacent shale from the soil trench, thus indicating their adaptability to the adverse oil shale conditions.Support for this research was provided by the White River Shale Corporation, Salt Lake City, Utah.