More evidence from the scence of the crime.
source: ICSD911 April 27, 2011
This is far more heat energy than a standard office fire can create.
The law of conservation of energy is an empirical law of physics. It states that the total amount of energy in an isolated system remains constant over time (is said to be conserved over time). A consequence of this law is that energy can neither be created nor destroyed: it can only be transformed from one state to another. The only thing that can happen to energy in a closed system is that it can change form …. You cannot get more heat than the process created initially, they cannot heat up more without added energy source.
When two isolated systems in separate but nearby regions of space, each in thermodynamic equilibrium in itself, but not in equilibrium with each other at first, are at some time allowed to interact, breaking the isolation that separates the two systems, and they exchange matter or energy, they will eventually reach a mutual thermodynamic equilibrium. The sum of the entropies of the initial, isolated systems is less than or equal to the entropy of the final exchanging systems. In the process of reaching a new thermodynamic equilibrium, entropy has increased, or at least has not decreased. Two objects such as air and steel will seek a thermodynamic equilibrium, (the same ambient temp, always cooling)
It follows that the entropy of an isolated macroscopic system never decreases. The second law states that spontaneous natural processes increase entropy overall, or in another formulation that heat can spontaneously flow only from a higher-temperature region to a lower-temperature region, but not the other way around. Heat always transfers to a colder object seeking temperature equilibrium.
The second law defines entropy, which may be described as a measure of deficiency of information, or uncertainty, about the microscopic details of the motion and configuration of the system, given only predictable reproducibility of bulk or macroscopic behavior as specified by macroscopic variables. For example, one has less knowledge about the separate fragments of a broken cup than about an intact cup, because when the fragments are separated, one does not know exactly whether they will fit together again, or whether perhaps there is a missing shard. Crystals, the most regularly structured form of matter, with considerable predictability of microscopic configuration, as well as predictability of bulk behavior, have small values of entropy; and gases, which behave predictably in bulk even when their microscopic motions are unknown, have high entropy.
Essentially heat always transfers from a hotter object to a colder object, and never the opposite and you cannot get more energy than is available, thus the pile would be in a constant state of cooling. 8 weeks later it is hot enough to ignite material (fuel) exposed to oxygen. Impossible in a conventional office fire, defys the laws of thermodynamics and conservation of energy. 8 weeks of cooling with water would make all the carbon based fuels wet and cold. These fires are from a heat source much hotter than an office fire.