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  • A stray dog stands outside the new, giant enclosure that covers devastated reactor number four at the Chernobyl nuclear power plant, Aug. 18, 2017 near Chernobyl, Ukraine. An estimated 900 stray dogs live in the exclusion zone, many of them likely the descendants of dogs left behind following the mass evacuation of residents in the aftermath of the 1986 nuclear disaster at Chernobyl.
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  • Anna Vlasinko greets two stray dogs she has named Alfa and Zuzka at the security post where she works opposite the new, giant enclosure built over the remains of devastated reactor number four at the Chernobyl nuclear power plant, Aug.19, 2017.
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  • Pavel "Pasho" Burkatsky, a professional dog catcher from Kiev, takes aim with a blow gun to shoot a tranquilizer dart at a stray dog in the exclusion zone around the Chernobyl nuclear power plant, Aug. 19, 2017. Burkatsky participating in The Dogs of Chernobyl project launched by the Clean Futures Fund, a U.S.-based charity that pursues humanitarian projects at Chernobyl.
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  • An aerial view shows the Soviet-era hammer and sickle on an apartment building in the abandoned city of Pripyat near the Chernobyl nuclear power plant, Aug. 19, 2017 in Pripyat, Ukraine, where stray dogs roam. Following the 1986 disaster approximately 116,000 people were evacuated from the immediate area.
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  • Jake Hecla, a graduate student in nuclear engineering at the University of California, Berkeley, and a volunteer with The Dogs of Chernobyl initiative, uses a spectroscopy device to measure gamma rays emitted from isotopes, including americium, which is derived from plutonium, and cesium lodged inside the body of an anesthetized stray dog recovering from surgery at a makeshift veterinary clinic inside the Chernobyl exclusion zone, Aug. 17, 2017.
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  • Anna Sovtus, a Ukrainian veterinarian working with The Dogs of Chernobyl initiative, tends to a stray puppy she had just washed at a makeshift veterinary clinic inside the Chernobyl exclusion zone, Aug. 17, 2017. Participants capture the dogs, study their radiation exposure, vaccinate, neuter and spay them, tag the dogs and release them back to the exclusion zone.
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  • A "frisker" Geiger counter, used to measure radiation, shows a reading of 1240 counts, approximately 20 times higher than normal, on the paws of an anesthetized stray dog at a makeshift veterinary clinic operated by The Dogs of Chernobyl initiative inside the Chernobyl exclusion zone, Aug. 17, 2017. Some dogs are also being outfitted with special collars equipped with radiation sensors and GPS receivers in order to map radiation levels across the zone.
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  • Terry Paik, a veterinarian from San Diego, Calif., volunteering with The Dogs of Chernobyl initiative, prepares to neuter an anesthetized stray dog at a makeshift veterinary clinic inside the Chernobyl exclusion zone, Aug. 17, 2017.
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  • A tagged, stray dog sniffs for food in a trash can outside the workers cafeteria inside the exclusion zone at the Chernobyl nuclear power plant, Aug. 18, 2017.
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  • A stray puppy walks along abandoned train tracks near the Chernobyl nuclear power plant, Aug. 19, 2017.
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