<P> The smoke and airborne particulates from the fires posed a threat to local communities on several occasions . Smoke and particulates were especially high in Gardiner, Montana . There, monitoring stations maintained by the Montana Department of Health and Environmental Sciences and the park recorded 19 days where recommended allowable particulate concentrations were exceeded . This was also the case near fires, and on 7 occasions at Mammoth, Montana, the location of the park headquarters . In no other surrounding communities were particulates found to be above acceptable levels . Smoke and haze made driving difficult and sometimes even dangerous . A number of fire fighters were treated at clinics for smoke and dust inhalation and a few for inadvertently inhaling fumes from a sulfur ignition near one of the geothermal areas . </P> <P> In the aftermath of the fires, erosion was a particular concern, especially as the rains were heavy the following year . Helicopters dropped millions of gallons of water on the fires, and water retrieval from a few small creeks actually dropped the water level temporarily . Stream flow was also affected by water - pumping operations . The more than a million gallons of diammonium phosphate - based fire - retardant material polluted some streams, but this too was transient and had no long term ill effects on water quality . Fire fighting foams used on wildfires differ from those used for other situations such as fuel fires . They are very low in toxicity and were believed to have completely dispersed by the spring of 1989 . </P> <P> The park service gave priority to life and property in their efforts to suppress the fires . Of the more than 1,000 structures located in the park, only 67 were destroyed . There were 400 structures in the Old Faithful complex and only 19 of these were destroyed, 12 of which were concessionaire housing units and relatively inexpensive to replace . Major tourist locations in the park such as the one at Old Faithful were heavily staffed by fire fighting crews and equipment, especially at times of immediate danger . Fire fighters used a variety of methods to establish safe zones in and near these complexes, yet every single visitor complex was evacuated by non-critical personnel at least once during the fires . </P> <P> Of the 38 backcountry patrol cabins used by park rangers and park staff, the only one lost to the fires was at Sportsman Lake, and it was rebuilt the following summer . However, fires did a lot of damage to numerous campgrounds, backcountry bridges, and 10 miles (16 km) of power lines and 300 utility poles . Some of the boardwalks used to keep tourists elevated above geothermal areas were also destroyed, but were quickly replaced . </P>

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