The U.S. Geological Survey is seeking qualified businesses for laboratory analytical services involving dissolved inorganic nutrient analysis of 407 marine porewater and seawater samples using Flow Injection Analysis. This is a sources sought notice for market research only, not a solicitation, and no contract award will be made at this time. The location for performance is in support of the Pacific Coastal and Marine Science Center, though no specific site is listed. No budget amount is specified. Responses are due by June 19, 2026, at 8:00 AM Pacific Time.