Isaak Brodsky was a Ukrainian Jew who claims to have been taken by German units in June 1943 to Babi Yar, a place where tens of thousands of Jews are said to have been shot and buried by the Germans in mass graves in late September 1941 (see the entry on Babi Yar). In an undated interview with the NKGB sometime in November or December 1943, he claimed that he was forced to exhume corpses from mass graves at Babi Yar and burn them on pyres. After that, the ashes were presumably sifted in search of valuables. He asserted that 70,000 bodies were burned at Babi Yar.
Brodsky’s statement is very brief and devoid of any specifics, making it difficult to assess his claims. His dating is noticeably off, though, because other witnesses claim that exhumations and cremation started only in mid-August 1943, not in June.
His claim that the ashes were sifted for valuables is naïve and betrays a lie, that all the remains of a pyre had to be sifted for unburned remains. Wood-fired pyres burn unevenly and leave behind lots of unburned wood pieces, charcoal and incompletely burned body parts, not just ashes (80% of leftovers would have been from wood, not corpses). Any sieve would have clogged with the first load. Moreover, any occasional rainfall would have rendered any burned-out pyre into a moist heap of highly alkaline, corrosive slush that could not have been processed at all. If 70,000 bodies were burned, then several thousand metric tons of cremation leftovers had to be processed. Just this job would have required hundreds of men to complete in time.
Cremating an average human body during open-air incinerations requires some 250 kg of freshly cut wood. Cremating 70,000 bodies thus requires some 17,500 metric tons of wood. This would have required the felling of all trees growing in a 50-year-old spruce forest covering almost 39 hectares of land, or some 87 American football fields. An average prisoner is rated at being able to cut some 0.63 metric tons of fresh wood per workday. To cut this amount of wood within five weeks (35 days) that this operation supposedly lasted would have required a work force of some 800 dedicated lumberjacks just to cut the wood. Brodsky claims his unit consisted only of 320 inmates, all busy digging out mass graves, extracting bodies, building pyres, and according to other testimonies also sifting through ashes, scattering the ashes and refilling the graves with soil. Brodsky says nothing about where the firewood came from.