• "Environmental" is usually thought of as meaning an issue such as hazardous materials being discovered on a job site, but it can apply to others, and those should be covered ahead of time in contracts.
• Some of the less-though-of environmental risks include water or stormwater pollution from construction, wetlands protection and proper handling and employee training for hazardous materials that are part of the construction methods.
• There also can be related, indirect issues such as a neighbor complaining of damage from waterflows that are not handled properly or the right to stop work without a penalty time if hazardous materials are turned up on the site.

From the article:

There are many dangerous intersections on a construction project. Whether you are talking about commercial contracts, regulatory compliance, accidents and fatalities, insurance coverage or employment issues, you need to plan for the risks that may arise. One of the more important crossroads where you can expect potential risk is where environmental and construction law meet. ...