A system can include a valve assembly including a first valve and a second valve in fluid communication with the first valve. The valve assembly can be configured to deliver one or more of a sample, a chemical (e.g., an acid, a base, an organic chemical, etc.), and a standard via flow of a working fluid facilitated by one or more syringe pumps. Further, the one or more of the sample, the chemical, and the standard can maintain a physical separation from the one or more syringe pumps during delivery of the one or more of the sample, the chemical, and the standard.