1. USDA–ARSUS Salinity Lab.RiversideCA92507
2. Dep. of Civil Engineering and Construction Engineering ManagementCalifornia State Univ.Long BeachCA90840‐5101
3. Quantitative Microbial Water Safety, Environmental Hydrogeology Group, Faculty of GeosciencesUtrecht Univ.3508 TCUtrechtthe Netherlands
4. CSIRO Land and WaterGlen OsmondSA 5064Australia