Building Capacity Dilemma

My school is in year 3 of our School Improvement Grant and our focus this year is building the capacity of our teachers and teacher leaders so that the work will continue post SIG. My dilemma as the SIG coordinator is that some of my teacher leaders are not on board with the initiatives so much so that they do not read emails or respond to requests from me to complete tasks. My issue is how do I build leadership capacity or sustainability if my teacher leaders are not on board with the plan. I meet with them once every two weeks and any initiatives are discussed with them during a leadership meeting where they have a voice. I encourage them to voice objections or concerns and I address those concerns. The coaches provide support for them as well. I worry that as soon as the  SIG ends, they are going to go back to doing what they were doing before SIG and that would be a great detriment to the students we serve.