Merck & Co Inc is constructing a 70,000 sq. ft. expansion to its site in Treyburn Corporate Park. The series of expansions which will culminate in an office built to LEED silver standards, two fill and finish facility buildings, a laboratory, a material and maintenance support facility, warehouse and energy center. The total cost of all expansions will be $900 million and will result in a total building footprint of 650,000 sq ft.