Complex sentence: He contacted David Pargament, chief of the Yarkon River Authority, who explained that 36 hours before the collapse, mosquito larvicide oil, a mixture of jet fuel and oil, had been sprayed on the surface of the Yarkon to suppress mosquitoes.
Split into simpler sentences: He contacted David Pargament, chief of the Yarkon River Authority. Pargament explained that 36 hours before the collapse, mosquito larvicide oil, a mixture of jet fuel and oil, had been sprayed on the surface of the Yarkon to suppress mosquitoes.