The problem with UV light as a disinfectant is the ability to shine it with enough illumination on all the waste matter is a sewer stream.
In a wastewater treatment plant, UV isn’t a nontypical disinfection process, but since solid particles in the wastewater stream provide shadows in the fluid flow, the UV process isn’t applied until the solids are removed from the fluid and turbidity is nearly absent.
In other words, from the time it leaves the infected body, till after it’s treated to about tertiary quality levels, the UV treatment isn’t practical. Even at tertiary levels, some algae and failed treatment systems don’t have checks and recircuiting to treat it until the water has been cleared absolutely for a rigorous UV treatment.
Since the portions infected are cells, they tend to flow with the fluids downhill in the sewer collection systems, but lift stations, pumps, manholes, and the pipes themselves would technically become infected.
These collection systems are not designed for full immersion, except for force mains, so they would all pass hazardous waste until replaced or fully cleansed. (It would be cheaper to seal them all and replace the entire system with new, until a cure is found, for certainty.
All the studies I’ve seen so far, (not many) provide some evidence that dried wastewater of previously infected fluids, can still contain infectious material in dark areas at ambient temperatures. Some cases where this has been discovered have been as long as 51 days after exposure in ambient, dark, partially washed conditions.
The evidence I’ve seen indicates past outbreaks might have burned out in rural areas, and perhaps the right circumstance occurred even years later for the same virons to then enter another host by chance,..beginning another infection process. No proof of this, but then again nothing proving this isn’t the case.
Incineration, as in the same process to cremate a body, or chemical disinfection, by longtime exposure and fully mixing the solution to disinfect ALL cells infected in the wastewater, or UV, by first filtering the wastewater in a multistage process until clear, without shadows by particulate matter, then intense UV disinfection, are all possible.
One problem with chemical treatments are the hazardous byproducts, which also cause environmental health problems.
I'm not talking about UV as a general means of sterilizing Ebola virus. I'm talking about it as a specific means of sterilizing Ebola in FOMITES, i.e., of reducing the danger of transmitting Ebola virus from inert surfaces to humans. Here that means disinfecting buildings.
And I agree that UV can't penetrate the surface of clots of relatively recent Ebola-laden secretions such as patches of blood, clots of mucus, with significant viral loads.
But UV can nail the lesser viral loads of smaller drying particles of secretions by Eobla victims, particularly those fixed in place on fomites and so subject to UV radiation from portable UV sources.