The problematic aspect of this situation is the NGO is http://en.wikipedia.org/wiki/Polish_Humanitarian_Organisation run by Janina Ochojska. These people are coming directly from the Solidarity movement of 1980s and are natural friends of Israel. The same applies to Mr. Pacewicz pictured above, who was running for 15 years (1995-2010) the biggest Polish daily, Gazeta Wyborcza. These people are not enemies of Israel and it would be wise not to antagonize them without a very good reason. Their intention are most likely neutral. As far as I can asses, because of their roots in the Solidarity movement, in any conflict they will always support the weak and oppressed, but I do not think they are strongly biased towards Palestinians or particularly interested in this conflict. They are just neutral people trying to help villagers in the West Bank who have no access to water. They were doing similar actions in Africa, former Yugoslavia and other places.
In three days, Greek coastguard rescues 2,500 migrants (Reuters)
from the article: Polish minister refuses to meet Israeli envoy over West Bank controversy