Comparing Soil and Pond Ash Feedlot Pen Surfaces for Environmental Management

Removing manure and replacing soil to maintain pen surfaces is expensive. Pond ash (PA), a coal-fired electrical generation by-product, has good support qualities. A study was conducted comparing the performance of pond ash (PA) surfaced pens with soil surface (SS) pens. Four pens of an eight pen series with dimensions of 7.3 m by 20.7 m were excavated to a depth of 0.5 m and resurfaced with PA. Eight heifers were housed in each pen (19 m2/head) for four feeding cycles that ranged from 73 days to 172 days. Following the feeding cycles, animals were removed, pens were cleaned and filled soil was brought in to restore pens to grade. A 1 kg sub-sample was removed from each pen to analyze for total mass (TM), total solids (TS), volatile solids (VS), percent volatile solids (VS%), moisture and ash content. Higher heating value (HHV) was estimated using the VS% and moisture. Surfacing pens with PA reduced the TM by 35%, TS by 34%, and ash content by 46%. The PA increased VS% by 70% and HHV by 75%. Also, the PA pens needed only ¼ the amount of fill material as the soil surface pens (SS). However, there were no differences measured in the total amount of VS removed. Harvested feedlot surface material (FSM) from the PA pens was much more nutrient and energy dense. This increased density, improved the economics of transport and handling, and allowed for energy recovery. Also, the PA pens were less erodible and required much less fill-material to maintain pen surfaces.