ABSTRACT
The addition of sewage sludge to land has the benefit of containing essential plant nutrients and organic matter, which improves soil physical properties (Pagliai & Sequi 1981, Smith et al. 1992a). It resulted in a 19-and 57-fold increase in extractable P in the 0-5 and 5-10 cm soil horizon respectively. Sludge application significantly increased plant biomass (both above ground and below ground), and plant density and foliar cover, although beneficial effects often decreased with time (Brofas et al. 2000, Thorne et al. 1998). Vegetation growth
1 INTRODUCTION
Mining of coal deposits has left a legacy of large numbers of abandoned mines with their associated spoil heaps which represent an ‘eye sore’ from the surrounding environment. The enactment of stringent laws requiring that the land be returned to an acceptable condition meant that land reclamation has now become normal part of the planning, approval and operation of most surface mines. The spoil heaps in the past were often slow to revegetate naturally, the surfaces tending to dry out in the summer leading to dust problems. Many heaps caught fire due to the residual coal causing a local hazard. These problems led increasingly to costly rehabilitation of tips and associated derelict land.
