1. SOURCES OF PATHOGENS COMMON PATHOGENS OF CONCERN Characteristics Escherichia coli(various strains) Salmonella Shigella Campylobacter jejuni Yersinia enterocolitica Vibrio cholerae Helicobacter Enterococci Cryptosporidium Oocysts 4-6 um PROTOZOA Giardia cysts 8-14 um long 7-10 um wide Trophozoite (feeding stage) 9-21 um long 5-15 um wide and 2-4 um thick (Maier et al, 2000) Coliform genera Escherichia, Klebsiella, Citrobacter and Entrobacter http://people.ku.edu/~jbrown/ecoli.html 1 to 3 um Escherichia coli Fecal Streptococci Enterococcus 1 to 3 um VIRUSES Over 140 types of Viruses: Hepatitis A virus Rotavirus One of the most common causes of infantile diarrhea Injection 10 viruses Enterovirus Group over 70 members Coxsackievirus Echovirus Poliovirus Norwalk virus Norwalk-like agents Other Virus Adenovirus Hepatitis E virus Calicivirus Astrovirus Adenovirus 70-100 nm Norwalk 27-34 nm Polio 28 nm 100 nm=1 um FACTORS CONTROLLING PATHOGENIC SURVIVAL, TRANSPORT AND FATE Fluid Properties 1. pH 2. Ionic strength 3. Organic mater 4. Temperature Porous Media Properties 1. Size 2. Composition 3. Isoelectric point 4. MeOx Coatings 5. Organic Material 6. Distribution of K, n, v, dispersivities PHYSICAL SYSTEM Pathogen Properties 1. Size 2. Surface Composition 3. Isoelectric point 4. Motility 5. Reproduction 6. Inactivation SIZE EXCLUSION AND BIOLOGICAL FACTORS IMPACTING CONCENTRAITONS (0.02 to 14 um) PHYSICAL PROCESSES IMPACTING CONCENTRATIONS Advection Dispersion Slug Source of Pathogens t3t3 t2t2 t1t1 Map View t1t1 t2t2 t3t3 C Distance from the source Peak concentration Dilution ! SCIENCE TO SUPPORT POLICY: Additional Research Needs 1. Pathogen survival studies. Protozoa, bacteria and viruses 2. Additional field transport and fate studies in varying hydrogeological settings applying pathogenic and non pathogenic tracers. 3. Development of predictive models for pathogenic transport in multiple groundwater settings. 4. More reliable analytical methods that allow separation of pathogenic and non pathogenic micro-organisms.. New analytical techniques, antibody assays,PCR, etc. (speciation) Increase sensitivity Cost considerations Controls on the Transport of Pathogens in Groundwater Systems William W. Woessner Department of Geology, University of Montana, Missoula, MT william.woessner@umontana.edu May 12-15, 2004 NAGT Geology and Human Health TEMPERATURE AND SURVIVAL OF PATHOGENS IN GROUNDWATER (Die-off or inactivation) BACTERIA HYDROGEOLOGIC PROPERTIES AND RESIDENCE TIME TRANSPORT RATES OF SOLUTES, PATHOGENS?? IN GROUNDWATER Dominate Material Expected velocity Time of Travel 30 m Clay and silt<0.01 to 0.05 m/d 3,000 to 600 d Sand0.05 to 1.0 m/d* 600 to 30 d Sand and Gravel1.0 to 10 m/d* 30 to 3 d Gravel10 to >100 m/d* 3 to < 0.3 d Rock (fract)0.3 to 8,000m/d * 100 to 0.004 d Rock (Karst)up to 26,000 m/d* up to 0.001 d * ( after Pekdeger and Matthess, 1983) EXAMPLE: VIRUS FIELD EXPERIMENTS, TRAVEL DISTANCES (Bales et al. 1995) (DeBorde et al., 1998) (DeBorde et al., 1999) (Rossi et al., 1994) Sand and Gravel Sand (Bales et al. 1997) Cape Cod, MA Emme Valley, Switzerland Cape Cod, MA Frenchtown, MT Erskine, MT Borden, ON +900m (Noonan and McNabb, 1979) Canterbury Plains, New Zealand (Peters et al., 1997) (Ryan et al., 1999;Piper et al, 1997) Castricum AR System, Netherlands 3 d 5 d 0.5 d 26 d 6 d 3 d 24 d Fractured Rock, Karst (Ls) 0 1020 304050 60 Transport Distance in meters 0.5 d (McKay et al, 2000)) TN, USA Sources of Groundwater outbreaks over 25 y, USEPA GW Rule Draft, 2000 HEALTH ISSUES AGENTSurvival Data Cryptosporidium oocysts* 540 d 4C* 50 25 50100days C Giardia cysts* 8C 77 d Fecal coliform E. coli *Canter and Knox, 1985 **Yates & Yates, 1987. Die-Off in log 10 /day = 0.018(T) - 0.144 where a 4 log drop was used. Virus** 90 to 135 d* 50 25 50100days C 8C ~no inactivation # 10C GW 180+ days observed Woessner 2002, unpublished data