The Low Compaction Grading Technique on Steep Reclaimed Slopes: Soil Characterization and Static Slope Stability

Abstract

Since the Surface Mining and Control Reclamation Act of 1977, US coal mining companies have been required by law to restore the approximate ground contours that existed prior to mining. To ensure mass stability and limit erosion, the reclaimed materials have traditionally been placed with significant compaction energy. The Forest Reclamation Approach (FRA) is a relatively new approach that has been successfully used to facilitate the fast establishment of native healthy forests. The FRA method specifies the use of low compaction energy in the top 1.2-1.5 m of the contour, which may be in conflict with general considerations for mechanical slope stability. Although successful for reforestation, the stability of FRA slopes has not been fully investigated and a rational stability method has not been identified. Further, a mechanics-based analysis is limited due to the significant amount of oversize particles which makes the sampling and measurement of soil strength properties difficult. To investigate the stability of steep FRA slopes (steeper than 20°), three reclaimed coal mining sites in the Appalachian region of East Tennessee were investigated. The stability was evaluated by several methods to identify the predominant failure modes. The infinite slope method, coupled with the estimation of the shear strength from field observations, was shown to provide a rational means to evaluate the stability of FRA slopes. The analysis results suggest that the low compaction of the surface materials may not compromise the long-term stability for the sites and material properties investigated.

Revegetation in abandoned quarries with landfill stabilized waste and gravels: water dynamics and plant growth – a case study

“…Plants growing in uncompacted LGM in a real environment, i.e., abandoned quarries, should not have this good performance because the only water source was LGM, which contained only 5 % water under natural precipitation. R. pseudoacacia growing in CL3 should have the best performance in the real environment although the germination, survival and growth were not significantly different from CL1 in our experiment, which was consistent with Jeldes et al (2013).…”

Erodibility of low‐compaction steep‐sloped reclaimed surface mine lands in the southern Appalachian region, USA

“…The study sites were devoid of native soils and forest cover, covered by surface mining spoils 1.5–2.0 m deep composed of silty‐clay soils mixed with gray shale and brown sandstone rocks. Classified by the Unified Soil Classification System (USCS), spoil materials were gravel with significant clay fines (GC) (Jeldes et al ., ). Average % rock by weight, defined as coarser than 25.4 mm (gravel size), were estimated at each study site as: Premium: 24.8%, National: 24.6%, Mountainside: 11%.…”

The Use of Passives and Impersonal Style in Civil Engineering Writing

“…In the journal articles, the use of active voice and human subjects was rare. Within literature reviews, author names were occasionally used as agents in sentences—for example, “Sweigard et al (2007a) have suggested correlations between…” (Jeldes, Drumm, & Schwartz, 2013, p. 1262)—but even those occurrences were relatively uncommon. Observations and recommendations were usually stated in passive voice, as in Sample 4: 4.…”

“…. " (Jeldes, Drumm, & Schwartz, 2013, p. 1262)-but even those occurrences were relatively uncommon. Observations and recommendations were usually stated in passive voice, as in Sample 4:…”