This from the 80s may give an estimate of what that pipeline might be like today. Think corrosion...
After the invasion and occupation of 1982, the Israel army established a series of hill-top fortresses in South Lebanon. By side of the Nabatieh road near Deir el Zahrani they dug a gravel pit for building up such a fortress. The pit enroached on the pipeline undermining it along the upper edge of the pit. Beside and just above the line is Tapline’s maintenance road which the local residents have recently been allowed to asfalt as access road to their houses. Some of those houses - including multi-story apartment blocks - use the line as a septic tank.
http://almashriq.hiof.no/lebanon/300/380/388/tapline/line/lebanon/deir-el-zahrani.html
wow..... thanks for that very informative effort