Michael D. Ells, R.S., M.S., DAAS, Professor
Environmental Health and Safety Management
College of Allied Health Sciences
Ferris State University, Big Rapids, MI

A Joint Project between:
The National Outdoor Leadership School (NOLS)
Leave No Trace, Inc. (LNT),
Mount Rainier National Park (MORA)
Ferris State University (FSU),
U.S. Forest Service, Wenatchee National Forest, Naches Ranger District (USFS)

Background:
During the fall 1995, a study was conducted to attempt to determine whether surface water runoff from the Muir Snowfield on Mount Rainier was contaminated with human feces and urine deposited by climbers and day hikers. The original study used fecal coliform (FC), fecal streptococci (FS), enterococci, Escherichia coli (Ec), Pseudomonas aeruginosa (Ps.a.), chloride ion, total dissolved solids (TDS) and conductivity as tracers of feces/urine contamination. The results of the study were unexpected in that no microbiological or chemical evidence of human waste contamination was found. Since the analytical methods used were found to be in control, the absence of evidence of contamination was an unexpected finding.

The results may have been influenced by the climatic conditions between October 1994 and October 1995. The 1994-5 snowfall was higher than average and was followed by cooler than average summer temperatures in 1995. As a consequence, the seeps noted (and found to be contaminated with fecal indicator organisms) in September 1994, did not materialize during the study period in fall 1995. This may have had a direct effect on the unexpected results. If runoff is contaminated at all, it may be only a transient situation and finding them in a collected sample may be serendipitous at best. It is also suggested that the majority of indicators may be flushed from the snowfield during the major snow melt that occurs from late May through July. If either of these is the case, it would be wise to begin sampling for indicators as early as possible in May, and continue the sampling and analysis through peak runoff in July/August. Since it is possible that the snow itself may be acting as a filtering and/or treatment mechanism, a controlled experiment was suggested wherein fresh feces be deposited on/in various snow sloped and the migration of fecal indicator organisms over time be determined.

During the 1995 project period, a computer modeling exercise was also conducted in an attempt to predict the flow paths of wastes resulting from the discharge of the liquid contents of the solar assisted toiled at Camp Muir (10,200'). Results of this exercise suggest that when the liquid is discharged beneath the permafrost at Camp Muir, it flows in a southwesterly direction within the underdrain system of the snowfield and cascades with the contents several waterfalls, over the west side of the snowfield, and into the valley of the Nisqually glacier. This is contrary to the pre-project hypothesis that the snowfield drained parallel to the trail over the snowfield to Camp Muir. The lack of positive analytical results tends to support the computer model.

During the project period, the Natural Resources Division of Mt. Rainier National Park (MORA) considered a suggestion by NOLS regarding the disposal of feces in the alpine environment. The suggestion involved the smearing of a "veneer" of feces over the surface of rocks and allowing a combination of meteorological, physical, chemical, and biological forces to "treat" the waste. While this has been suggested and may be successful in tropical and semi-tropical rain forest areas, its effectiveness in the alpine environment was questioned. Public Health concerns were also raised and, lacking support from a well defined scientific study, the park deferred on this recommendation.

Summer 1999:
During the summers 1999 and 2000 a multi-part project was conducted to address human waste disposal in various environments and, specifically, to address smearing. In 1999 the project addressed: the fate of feces and fecal microorganisms in human waste deposited on snow and smeared on rocks in the alpine environment.

Snow Specimens:
This project involved dropping fecal specimens on the snow surface of the Muir Snowfield on Mount Rainier and also examined the suggestion of smearing as a method of human waste disposal. The Muir Snowfield, at an altitude of approximately 8500', was the site of the experiment where feces was dropped onto the snow surface and samples of snow were removed from beside and beneath specimens for an 8 week period of time as weather permitted. Initial fecal specimens were also taken and the numbers of fecal microorganisms (fecal coliform, fecal streptococcus, E. coli, Pseudomonas aeruginosa) per gram determined. Initial snow and soils samples indicated that each were virtually uncontaminated with any of the fecal indicator organisms. Specimens were also photographed bi-weekly.

Results of the snow specimens indicated that while the snow surrounding each fecal deposit was immediately contaminated with a brown stain that was contaminated with fecal microorganisms, following two weeks of exposure, this stain and the contaminating organisms disappeared. It was also found that as the exposure period lengthened, the number of microorganisms contaminating the exterior of each fecal specimen decreased. Additionally, most of the specimens also appeared to desiccate and fragment into smaller and smaller pieces as the study progressed. Snows contaminated with these fecal flakes were found to be un-contaminated with fecal microorganisms. Samples taken from internal portions of feces at the conclusion of the study period revealed that significant numbers of fecal indicator organisms continued to survive and that their death rate seemed to lag behind that of surface organisms. Where a one log decrease per week was seen in surface bacteria, internal samples indicated a one log decrease over a two week period of time.

Smearing Specimens:
Concurrently, tare weighed rocks in a nearby fell field were smeared with either a thin (2-3 mm) or a thick (4-6 mm) veneer of feces. On a bi-weekly interval, rocks were reweighed to determine fecal specimen desiccation. Additionally, samples of fecal material and of surrounding soils were obtained to determine the rate of fecal microorganism die-off within the feces and to determine the rate and extent of fecal microorganism runoff onto the surrounding soils. The smearing experiment was conducted over a 10 week time period (early July - mid September).

Results of the smearing show that the smears rapidly lost weight, that the numbers of microorganisms in the fecal smear fell rapidly during the study period, and that each smear had a tendency to flake off and blow away. In fact, at the conclusion of the study period, the rocks originally supporting the fecal smears appeared to be washed clean and no remnants of the original fecal smears could be found. Additionally, with the exception of one sample, soils beneath or beside the feces smeared rock were found to be uncontaminated. It is hypothesized from both experiments that with the exception of initial contamination, the extreme alpine conditions (cold, wind, desiccation, UV radiation) combined to kill fecal microorganisms on the exterior of the fecal snow specimens and feces smeared rocks prior to the feces desiccating, flaking off and being blown downwind. The depth of the fecal veneers did not seem to make a significant difference in the death rate of fecal indicator microorganisms. Snows and soils contaminated with fecal remnants were found to be uncontaminated with fecal microorganisms. Research questions resulting from this study were: Would the same results be found if the experiment was conducted in a temperate forest environment? In an arid environment? Was the disappearance of the fecal smears the result of the environmental conditions or were other factors, such as coprophagous (feces eating) animals involved.

Summer 2000:
Two experiments were begun in early June 2000. Both involved smearing two tare weighed rocks with a thin fecal veneer, and two with a thick fecal veneer, however, contrary to the exposure method in 1999, all four smears at each site were placed in large metal dog crates that had been covered with _" hardware cloth and staked to the ground with bungee cords. The purpose of the covered dog crates was to discourage coprophagous animals.

The first experiment site was in the temperate rain-forest environment of MORA near Longmire. This densely forested site has summertime temperatures of 60-70oF, high humidity, and dense shade. The second site was near Naches, Washington. This site was characterized by sparse growth of Ponderosa Pine, and sagebrush, having summertime temperatures averaging over 90oF with low humidity and no shade. Samples of soils and initial fecal samples were taken and analyzed for FC, FS, Ec and Ps.a. Initial microbiological examination of samples of soil from each site indicated that the soils were uncontaminated with fecal indicator microorganisms. The sites were visited biweekly when samples of feces were obtained for analysis, the rocks + feces were reweighed, and photographs of the samples were taken. Sample retrieval and analysis continued for 14 weeks through early September. Final weights and photographs were taken following 18 weeks of exposure in early October.

Results:
Smears at both sites were found to desiccate at approximately the same rate however the arid site thick smear lost a greater percentage of its weight than did the temperate site thick smear. This was undoubtedly due to the more arid conditions at Naches. Microorganisms survived for a much longer period of time, and at much higher levels per gram of feces in the temperate forest (Longmire) site than at the arid (Naches) site. Again, it is suspected that the reason for this is the decidedly less hospitable conditions at the arid site than at the temperate forest site. Additionally, as would be expected, the higher rainfall at the temperate site enabled fecal microorganism runoff to the soils at a higher extent than the arid site where it did not rain during the experiment. Soil was determined to be contaminated on 3 of the 7 sample dates at the temperate forest site, rather than contaminated on only one occasion at the arid site. Weight measurements indicated that smears did become re-hydrated during rain events and then re-desiccated during dry periods. Rain during the first three days of exposure kept the temperate site feces moist and some smears became infested with insect larvae during this time. Insect larvae were never found to have infested the smears at the arid site. The appearance of the smears was also different and distinctive. Temperate forest smears appeared to shrink and become flat and appeared dense (although they were light in weight). They were also found to be periodically supporting fungi. Arid smears, on the other hand, were very fibrous and "sponge-like" in appearance. The light and airy nature of the arid smears may be the reason why the fecal indicator microorganisms died off at a faster rate that that of the temperate site. It did not appear that the depth of the fecal veneer played any significant role in the death rate of microorganisms. Finally, although this experiment was conducted over a exposure period nearly twice as long as the 1999 alpine study, at the conclusion of the 125 day exposure, some feces remnants remained on every one of the four rocks at each site. This indicates that coprophagous animals were indeed at least partially responsible for the disappearance of the fecal smears in the 1999 alpine experiment.

Public Health Impacts:
CAUTION: Extreme care must be taken in the interpretation of the experimental results when using them to assess Public Health Impacts. The reader is reminded that these studies used only Fecal Coliform, Fecal Streptococci, Enterococcus, Escherichia coli, and Pseudomonas aeruginosa as fecal indicator organisms. What it more important is what organisms were NOT assessed including viruses and protozoa (Giardia, Cryptosporidium). These latter organisms have been found to survive for much longer periods of time that the bacteria assessed. Therefore, although no or few fecal bacteria were found to contaminate alpine snows or soils or arid soils, this does not mean that they were totally uncontaminated with potential disease causing viruses, protozoa or other bacteria.

The 1999 experiment assessed the impacts of a volume of approximately seven (7) daily bowel movements in a relatively limited area. The 2000 experiments assessed the impacts of a volume of less than one (1) daily bowel movement, also in a relatively limited area. The effects of several, tens, scores, or hundreds of bowel movements in a relatively limited area/s along a popular hiking trail was not assessed and can only be surmised. Experimental results indicate that smearing might be an acceptable method of human waste disposal in alpine or arid areas. Further studies that need to be conducted relate to the size of areas needed for varying numbers of users; potential for transmission of disease organisms (pathogens) by various animals; user surveys to determine the acceptance/acceptability of smearing by the hiking/climbing community. Additionally, it is understood that a scree area on the Grand Teton in Grant Teton National Park has been used as an unofficial smearing area for an estimated 30 years. It would be interesting to study the microorganism content of runoff and soil in and around this area.