Joseph F. Malina

An evaluation of geotextiles for temporary sediment control

The performance of geotextiles for sediment control was evaluated in the field and laboratory. Runoff samples collected in the field indicated that essentially no sediment removal was attributable to filtration by the fabric. Silt fences also had little influence on the turbidity of the discharged runoff. Total suspended solids removals of 68 to 90% were found in flume tests in which silt fences were installed. The removal efficiency was correlated with the average detention time of the impounded runoff behind the fence. Flow rates through the fences under field conditions were two orders of magnitude less than would be calculated using standard ASTM index characteristics of the fabrics. This discrepancy resulted from clogging of the fabric with sediment and from the turbulent flow through the fabric openings at the hydraulic heads on the fabrics when used as silt fences. The Center for Research in Water Resources, The Center for Research in Water Resources, The University of Texas at Austin.

Process framework for identifying and prioritizing water quality improvement for meetings TMDLs in Texas

The objectives of this research are to help the Texas Department of Transportation (TxDOT) anticipate the requirements of the Total Maximum Daily Load (TMDL) process and to have the data at hand to respond if TxDOT is identified as contributing to the impairment. An interactive geographic information system (GIS) map of the impaired streams was created in ArcGIS to aid TxDOT in identifying where the impaired segments are in relation to major highways and roads. Runoff quality data from TxDOT facilities in the state were compiled and compared to water quality standards to determine constituents of concern. Existing Best Management Practices (BMPs) were assessed for their effectiveness in treating highway runoff. A toolbox of appropriate BMPs for specific pollutants was developed from this assessment. The results from this study indicate that the major causes of impairment of water bodies in Texas are bacteria and low dissolved oxygen concentrations. Unfortunately, there are currently no BMPs that effectively address pathogens and nutrients. It is recommended that TxDOT pursue a pollutant trading program as an alternative to implementing BMPs if required to reduce loadings of pollutants to impaired segments.

Application of Bioactive Substances in the Biogas Technology

A new scientific-technological concept of the utilization of wine and distillery wastes is proposed. The results of complex research are given, related to the effect of biologically active substances (BAS) on biomethane and biohydrogen emission from the distillery wastes. It was shown that the test substances can provide a 3−4 times increase in fermentation efficiency, enhance the methane contents in biogas up to 90−95 % and activate the dehydrogenase thus stimulating the biochemical process. The kinetic indicators of processes and mechanism of BAS effect on anaerobic fermentation are discussed.