The project manager's responsibility is to ensure that the project aligns with the organization's values and objectives. In this case, the project's viability and success are being questioned due to concerns about compromising land erosion. If the project no longer aligns with the company's commitment to environmentally sustainable projects, it is appropriate for the project manager to propose closing the project.
This decision ensures that the organization maintains its reputation for delivering environmentally responsible initiatives1.
References:
1.Nigeria Erosion and Watershed Management Project (NEWMAP) - The World Bank