An issue which has been raised so often that it has become synonymous with nuclear power is that of nuclear waste and the storage of it. Through decades of clamoring by anti-nuclear groups and individuals there is no doubt in the mind of the average person that the issue of many tons of highly dangerous, highly radioactive nuclear waste is both real and the primary reason to switch to so-called renewable technologies such as solar and wind power. Due to the strong anti-nuclear lobby and public mood also due to the nuclear threat of the Cold War precious little effort has been made to examine in how far this nuclear waste issue is real or imaginary.
The premise of the suggested nuclear waste issue is that nuclear reactors will always produce large amounts of highly-radioactive materials which will have to be stored for thousands of years, forming a lethal risk to current and future generations. Hereby we have a few items of importance: that nuclear reactors produce large amounts of highly-radioactive material, that this will have to be stored as waste, and that this forms a major risk to humanity.
Starting with the first item, less than a minute of research will show that current commercial reactors use only about 0.65% of the energy contained in the uranium as it is mined, and less than 5% of the enriched uranium fuel. The major alternative reactor design, so-called breeder reactors  which due its neutron economy are capable of generating more fissile material (fuel) than it consumes. This includes the actinides, the transuranic elements which are highly radioactive due to their unstable nature. A breeder reactor in combination with a reprocessing step for removing neutron-absorbing fission products (low-radioactive elements) can use virtually all of the energy contained in the uranium fuel, reducing the fuel requirements by about two orders of magnitude (90+% versus <5% efficiency).
With a breeder reactor design such as the Integral Fast Reactor  (cancelled in 1994 by the US Congress despite working as expected) or its successors Sodium-Cooled Fast Reactor (SFR)  and S-PRISM , so-called Generation IV reactors, the only waste would be long-lived fission products (LLFP) , which have half-lives on the order of 200,000 to millions of years and sometimes have such low radioactivity that these elements can still be found in nature dating back to the formation of the universe. Only seven of these are relevant due to having relatively short half-lives:
None of these seven isotopes form a risk to biological life. Technetium-99  as the most short-lived of these is commonly injected into humans in the form of Tc-99m, an isomeric form of Tc-99, for medical testing where it transitions back into the Tc-99 form inside the human body and is deemed virtually harmless due to the half-life of 211,000 years.
If we start building Generation IV reactors such as the ones listed above now, we can use existing ‘waste’ from Gen-II and III reactors in them, while adding small amounts of fresh uranium fuel from time to time. In combination with uranium mining from seawater we would have virtually infinite amounts of energy, with no dangerous waste to store. This takes care of the second point, and the third point.
When talking about radiation hazards, one would be wise to consider natural sources of radiation, such as granite . Many types of granite contain significant amounts of uranium and thorium, which decay into radioactive radon gas, which is the number two cause of lung cancer in the USA after smoking. A building with for example a basement on granite bedrock is likely to collect this gas, resulting in significant cancer risk for its inhabitants. While deemed harmless by most, granite and other types of rock apparently are a far great radiation risk than that imagined for the waste output of nuclear reactors.