21 F. Supp. 3d 784
W.D. Tex.2014Background
- USIBWC discovered high levels of arsenic and lead (soil and groundwater) at the American Canal/Dam site in El Paso during 2002 investigations; EPA/USIBWC alleged Asarco historic smelting was a major source.
- Asarco (former smelter owner/operator) settled with the United States in bankruptcy for ~ $19–22 million to resolve CERCLA liability related to the USIBWC Site; remediation had not yet been performed.
- CEMEX, Inc. is successor to Southwestern Portland Cement Co. (SWPCC), operator of a cement plant (the Plant) near the USIBWC Site; CEMEX Construction is successor to a quarry operator (Toro Quarry) and operated a ready‑mix plant at the Quarry.
- Evidence showed cement kiln dust (CKD) and other dust throughout the Plant; CKD can contain arsenic and leach arsenic rapidly when contacted by water; parties disputed whether CKD actually left the Plant or Quarry and whether it migrated to the USIBWC Site.
- Experts agreed surface runoff from the Plant would flow to the Rio Grande upstream of the American Dam; plaintiff’s experts testified CKD or fugitive emissions plausibly migrated (via runoff and air) to the USIBWC Site and contributed to soil and groundwater arsenic; defendant’s experts disputed significant migration or contribution.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Proper causation standard in a two‑site CERCLA contribution claim (must plaintiff show defendant’s waste actually migrated?) | Asarco: use burden‑shifting test (Westfarm) — plaintiff shows same/similar contaminant at both sites + plausible migration pathway; then burden shifts to defendant to disprove causation. | CEMEX: plaintiff must prove actual contribution (KRSG/Thomas approach), including fingerprinting when contamination is off‑site. | Court adopts Westfarm approach: plaintiff need only show same/similar contaminant and plausible migration pathway; defendant bears burden to disprove contribution. |
| Liability of CEMEX for Quarry (Toro Quarry) | Asarco: Quarry contains arsenic in limestone and fugitive emissions/runoff could have transported arsenic to USIBWC Site. | CEMEX: Quarry emissions and groundwater show background arsenic and no demonstrated migration pathway to USIBWC Site. | Court: Asarco failed to show a plausible migration pathway from the Quarry to USIBWC Site; CEMEX not liable for Quarry. |
| Liability of CEMEX for Cement Plant (Plant) | Asarco: Plant produced CKD containing arsenic; surface runoff/culverts lead to Rio Grande upstream of Dam; CKD can leach arsenic into river/groundwater and fugitive emissions could deposit on USIBWC Site. | CEMEX: Much dust may not have been CKD or was contained/crusted; contributions are negligible versus Asarco; fingerprinting shows only Asarco fingerprints. | Court: SWPCC/CEMEX is a responsible person for the Plant; plaintiff proved presence of CKD and a plausible migration pathway (runoff and fugitive dust); CEMEX, Inc. is potentially liable under §107(a). |
| Allocation of response costs between Asarco and CEMEX | Asarco: seeks contribution (~$11M) — CEMEX should bear significant share given Plant contributions. | CEMEX: any contribution is minimal or zero; Asarco is dominant source. | Court: Equitable allocation using Gore factors — Asarco bears majority; CEMEX liable for a small but nontrivial share: ~5% (~$1,100,000) to reimburse Asarco (plus interest). CEMEX Construction not liable. |
Key Cases Cited
- Amoco Oil Co. v. Borden, Inc., 889 F.2d 664 (5th Cir. 1989) (discusses CERCLA causation and remedial purpose)
- Dedham Water Co. v. Cumberland Farms Dairy, Inc., 889 F.2d 1146 (1st Cir. 1989) (two‑site causation; plaintiff need not show actual migration from defendant)
- Westfarm Assocs. Ltd. v. Wash. Suburban Sanitary Comm’n, 66 F.3d 669 (4th Cir. 1995) (adopts burden‑shifting test for two‑site cases: contaminant + plausible pathway establishes prima facie case)
- Kalamazoo River Study Grp. v. Rockwell Int’l Corp., 171 F.3d 1065 (6th Cir. 1999) (advances a stricter requirement that plaintiff show actual contribution; court discusses limits of mere possibility)
- Monsanto Co. v. United States, 858 F.2d 160 (4th Cir. 1988) (allocation and burden considerations in CERCLA actions)