The EPA is a government bureaucracy with about 15,000 employees and over 70,000 pages of rules and regulations. This needs to be simplified so there is a better balance between economic growth and environmental protection.
If you ever worked in a government bureaucracy, they do things in a backwards way compared to the free market. For example, there is a white collar career ladder, where you advance upwards, based on performance, politics, and years of company service. Since they do hire good people, what tends to happen is you get top heavy, with too many good senior level managers for the job.
Often this results in the need to define new parallel positions, expanding the bureaucracy, laterally at all levels. Instead of one manager of water quality, it become manager of cold water quality, manager of warm water quality and manager of hot water quality. This lateral expansion is needed to promote all the good people who play by the rules of company politics. At this point, if these senior staffers are scientists, they are no longer doing science. Their main job is paper work, meetings and budgets. Some scientists, in the science jobs, prefer to stay there. Others, prefer the politics and want to leave the lab for the front office. Now they only talk science.
As far as budgets, you are never rewarded for saving money and being efficient. You will get punished for being efficient, with less funding next year. Power and prestige, in management, is based on how much money, resources and manpower you control. Nobody up top wants to give anything back since this reflects on their prestige status; bigger is better. The system is designed for prestige and not service. It has to support a lot of chiefs with the braves often frustrated by the waste and lack of efficiency.
At the end of the fiscal year, if you have extra money, you are asked to spend it during June jubilee. June jubilee can be fun, since you can get that back up microscope, you may not need, but would like to have just to be safe. This helps to balance the budget in antiquation of the future increase requested. It also makes management look smarter since they hit the budget on the dot.
Trump wants the EPA to act more like the private sector, with the tax payer in mind. The upper level scientists who will get the ax don't do science anymore but will need to get back to their roots.