With my extensive background in chemical engineering and software development, I am ideally suited to take on your project. Having worked as a chemical engineer, I understand the intricacies of modeling chemical systems and solving design problems. My proficiency in Python - which is a prerequisite for your project - strongly aligns with the EPA code you shared.
The interface you described, aimed at streamlining input and improving efficiency, is something I have successfully delivered in previous projects. Drawing from my experience in machine learning, data science, and automation, I will not only create a user-friendly dropdown interface but also set up a database system that will incorporate all the chemicals' properties. This will make data entry more seamless, reducing errors and saving time for you and your team.
All in all, choosing me for this project means benefiting from my diverse skillset in chemical engineering, software development, machine learning, statistics,and programming expertise to create an intuitive interface that meets your exact needs. I am excited about the prospect of contributing to better water treatment models - let's get to work!