Photo: Ingmar Runge, CC BY 3.0 via Wikimedia Commons
Within the 10-km zone is a large former secret radar installation that the Soviet government used to detect missiles, the Duga 3 Radar. From Pripyat, it is easy to see in the distance, if looking from a point of elevation.
Duga was an over-the-horizon radar (OTH) system used in the Soviet Union as part of its early-warning radar network for missile defence. It operated from July 1976 to December 1989. Two operational Duga radars were deployed, with one near Chernobyl and Liubech in the Ukrainian SSR, and the other in eastern Siberia.
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Although radiation detectors (Geiger counters, etc.) tick at many places in the Exclusion Zone, most of the measured activity is very close to natural background levels or slightly above. There are however notable hot spots, where radiation levels are many hundreds or even thousands of times higher than background radiation. If you've never heard a Geiger counter tick, then these are perfect locations to test them out! If you're brave, a good location is this waste separation facility, with radiation levels of ca. 1 mSv/h close to the ground. The radiation is concentrated in an area of about 10 x 10 m. It's recommended to stay no longer than 5 minutes in the area, which should be more than sufficient to make a video recording of a ticking Geiger counter!
МТС (машинно-тракторная станция)
A mechanic workshop where agricultural vehicles were maintained, refurbished, and scrapped for parts before the accident. During the cleanup it was used for the maintenance of vehicles used by liquidators, and the site has been abandoned ever since. Fertilizer machines, corn harvesters, and numerous other agricultural vehicles are now rusting away in a birch forest that is overgrowing them. There is a pick up truck with a trefoil logo on its door, a great place for a souvenir photo. For those interested, there are numerous radiation hot spots in and around the workshop, which can be found with a Geiger counter.
A roadside concrete mixing plant with 4 hoppers and supporting facilities that transferred and produced the concrete that was used for the construction of the Sarcophagus. Some rubble with white tiles has been dumped on the site after the completion of the construction work, and is noticeably radioactive (~ 5 µSv/h).
A strip of birch and pine forest that was contaminated with the worst fallout, killing off most of the vegetation because of the intense radiation and turning trees reddish brown — hence the name. Trees were felled and buried in trenches by liquidators, then covered over with soil and occasionally concrete slabs.
The Red Forest is still the most radioactive area in the Exclusion Zone, and marked with radiation warning signs but not fenced off in any way. As of 2019, radiation levels vary between 4 µSv/h (microsievert/hour) and 15 µSv/h, with local hot spots reaching 40 µSv/h. Spots where material is buried have considerably higher dose levels. It is recommended to stay no longer than 90 minutes around these hot spots (equivalent to a daily accumulated those of 60 µSv which is the threshold for radiation workers). As the most radioactive outdoor area in Europe, exploring the Red Forest is an experience on its own, but adequate safety measures must be taken. Wear protective wellies, carry an electronic dosimeter (PED) with warning threshold set no higher than 20 µSv/h, and do not touch anything. When leaving the Red Forest, protective wellies must be decontaminated (washed off).
If possible, take a geiger counter or similar radiation measurement device with you into the Red Forest to compare activity levels at different locations. Birch trees and lichen are particularly prone to absorbing radioactive Cesium (accounting to the majority of radiation after 32 years), and often read much higher radiation levels with peaks up to 3,000 counts per second not exceptional. Make sure the probe of the geiger counter does not touch any of the vegetation to avoid contaminating it!
On the shore of the lake near the cooling water intake canal entrance is a fish hatchery with supporting buildings. Fishery was an economically interesting opportunity in the lake because it never froze over due to the elevated temperature of the water being used to cool the 4 operational reactors. This meant fishing was sustainable year round, and the fish caught were larger than elsewhere. The fish hatchery was abandoned after the accident, and one of the few buildings within a 5 km radius around reactor no. 4 that are not related to the power plant. The hatchery is not fenced off and can be visited, along with the remains of its floating dock. The shore offers a nice viewing point for the lake.
At the time of the accident, 2 more reactors of the same type as no. 4 were under construction to the south east of the existing 4 reactors. Construction was efforts were suspended indefinitely after the accident, and the nearly completed reactors were never fuelled. The structure is being dismantled as of 2019, but its half completed cooling towers remain. The northern tower is about twice as tall as the southern tower and can be seen from a distance. The concrete rebar sticking out from the top rim is a silent witness of the abruptness with which construction was halted.