New Castle County contains 238 EPA-regulated facilities, 10 of which are currently flagged for significant noncompliance. The county also hosts 12 Superfund sites and 28 TRI chemical reporters. EPA has assessed $12.7M in lifetime penalties and TRI reporters disclosed roughly 4.4M lb of on-site releases. That facility count is well above the Delaware state average of 63 per county.
| Site | City | Status |
|---|---|---|
| E I Du Pont De Nemours Co Inc Newport Pigment Plant Landfill | Newport | Construction complete |
| Halby Chemical Co | New Castle | Ready for anticipated reuse |
| Army Creek Landfill | New Castle | Ready for anticipated reuse |
| Koppers Co Inc Newport Plant | Newport | Remedy selected |
| Harvey Knott Drum Inc | Kirkwood | Ready for anticipated reuse |
| Delaware Sand Gravel Landfill | New Castle | Construction complete |
| Newark South Ground Water Plume | Newark | Listed on NPL |
| Standard Chlorine Of Delaware Inc | New Castle | Cleanup underway |
| Tybouts Corner Landfill | New Castle | Ready for anticipated reuse |
| Delaware City Pvc Plant | New Castle | Construction complete |
| Hockessin Groundwater | Hockessin | Listed on NPL |
| East Basin Road Groundwater | New Castle | Listed on NPL |
| Facility | City | On-site (lb) | Status |
|---|---|---|---|
| Delaware City Refining Company Llc | Delaware City | 4.3M | Sig. violation |
| Sun Chemical | Newport | 29.7k | Compliant |
| Air Products & Chemicals, Inc. H2 Smr Plant At Delaware City Refining Company | Delaware City | 25.8k | Compliant |
| Hay Road Energy Center | Wilmington | 18.2k | Compliant |
| Veolia - Red Lion Plant | New Castle | 8.2k | Compliant |
| Croda, Inc. Atlas Point Plant Site | New Castle | 6.2k | Sig. violation |
| Medal L.p., Air Liquide | Newport | 3.7k | Compliant |
| Prince Minerals Llc | New Castle | 3.4k | Penalties |
| Agilent Techs Inc Newport Site | Newport | 2.1k | Compliant |
| Rogers Corporation - Bear | Bear | 1.6k | Sig. violation |
| V & S Delaware Galvanizing Llc | New Castle | 729 | Compliant |
| Us Army National Guard River Road Training Site Range, De | New Castle | 600 | Compliant |
| Noramco | Wilmington | 293 | Compliant |
| Dupont Electronic Materials Cmp, Llc | Newark | 243 | Compliant |
| Rohm And Haas Electronic Materials Cmp Inc | Newark | 219 | Compliant |
| Owen Steel Company | Wilmington | 20 | Compliant |
| Kuehne Chemical Company Inc | New Castle | 9 | Compliant |
| Aearo Technologies Llc | Newark | 5 | Compliant |
| Facility | City | Penalties | Last Inspected |
|---|---|---|---|
| Delaware City Refining Company Llc | Delaware City | $820.0k | 2025-07-24 |
| Rogers Corporation - Bear | Bear | $11.2k | 2024-05-15 |
| Delaware Auto Salvage | New Castle | $10.0k | 2022-12-15 |
| Divi Enterprise | New Castle | $10.0k | 2023-11-03 |
| Croda, Inc. Atlas Point Plant Site | New Castle | $7.5k | 2025-12-09 |
| Greenville Country Club | Wilmington | $0 | 2025-09-23 |
| Iko Production Wilmington Inc. | Wilmington | $0 | 2025-07-08 |
| Industraplate Corp | Wilmington | $0 | 2024-04-23 |
| Clean Loop Group Llc | New Castle | $0 | 2024-07-30 |
| Diamond State Port Corporation - R/R Flood Controls | Wilmington | $0 | 2024-09-27 |