Final answer:
A professional engineer can ethically take on a sustainability project even if it's not 100% sustainable, as long as it aligns with the client's needs and legal/professional standards. A sustainable ethic involves compromises between environmental, economic, and societal goals. Practical constraints often lead to solutions that balance these factors.
Step-by-step explanation:
It is ethical for the professional engineer (PE) to take on a project that is no longer 100% sustainable if that aligns with the client's preferences and constraints while still adhering to legal and professional standards. Being 100% sustainable is an ideal that carries significant challenges such as higher costs and technological constraints, which might not align with every client's needs or values. Sustainability is about managing environmental impact while balancing economic outputs and societal preferences.
The concept of the Production Possibility Frontier (PPF) in economics can represent the trade-offs between environmental protection and economic output. As the earth's resources are not unlimited, conserving resources for their continual use in the future forms the crux of a sustainable ethic. However, practical application often requires compromise to meet stakeholder expectations, available resources, and cost-benefit considerations, leading to solutions that may be less than 100% sustainable but still aim for reduced environmental impact.