## Facts

- Aerojet-General Corporation and a subsidiary leased a ranch property in Sacramento County, California, from 1960 to 1970 under a lease requiring return of the premises in as good condition as received, reasonable wear and tear excepted.
- Plaintiffs later purchased the property from the lessors’ estate in 1975.
- Plaintiffs alleged that during the lease Aerojet disposed of hazardous wastes on the property and left toxic substances in the soil after vacating.
- Plaintiffs alleged the contamination posed an ongoing threat to health and safety and interfered with use and enjoyment of the land.
- Regulatory authorities required testing and threatened to require abatement, exposing plaintiffs to potential cleanup costs.
- Plaintiffs sued on multiple theories, including nuisance, trespass, negligence, negligence per se, strict liability, equitable indemnity, declaratory relief, and a claim under Business & Professions Code § 17200.
- The trial court sustained a general demurrer to all causes of action without leave to amend and entered a judgment of dismissal.

## Issues

1. Whether current owners may sue a prior lessee for public and private nuisance based on hazardous conditions existing on the owners’ own land.
2. Whether hazardous substances remaining in soil after the lease ended can constitute a continuing trespass against later owners.
3. Whether the nuisance, trespass, negligence, and strict liability claims are time-barred or may proceed under continuing nuisance/continuing trespass theories.
4. Whether the lease terms or lessor consent bars nuisance or trespass liability as a matter of law at the pleading stage.
5. Whether a Business & Professions Code § 17200 claim may rest solely on past disposal conduct that has ceased.

## Decision

- The Court of Appeal reversed the judgment of dismissal in part and remanded.
- The court held the nuisance statutes are not limited to neighbor-versus-neighbor disputes and can reach hazardous conditions on the plaintiff’s own property allegedly created by a prior lessee.
- The court held plaintiffs adequately pleaded continuing nuisance and continuing trespass based on the alleged ongoing presence of hazardous waste, so dismissal on statute of limitations grounds was not required at the demurrer stage.
- The court rejected, at the pleading stage, the argument that the lease or lessor consent provided blanket authorization to create or leave a toxic condition, given the lease’s restoration clause.
- The court treated the § 17200 theory more narrowly, concluding it generally requires ongoing business conduct and is not supported by solely historical acts long since ended.

## Legal Principles

- California Civil Code nuisance provisions are broadly framed and are not confined to interferences originating from neighboring land; hazardous conditions on the plaintiff’s own land can support nuisance claims when statutory elements are pleaded.
- A lease or lessor consent does not, as a matter of law, immunize a tenant from nuisance liability where the alleged condition exceeds permitted use or conflicts with an obligation to return the premises in good condition.
- A condition may constitute a continuing nuisance when the alleged interference and harm persist over time; in such cases, limitations analysis may treat the wrong as recurring rather than completed.
- A continuing trespass may be pleaded where a physical invasion or substance remains on the land and continues to interfere with the owner’s possessory interest.
- On demurrer, pleaded material facts are taken as true; dismissal without leave to amend is improper if viable causes of action are stated or there is a reasonable possibility of curing defects by amendment.
- A Business & Professions Code § 17200 claim generally requires an ongoing or current unlawful, unfair, or fraudulent practice, not merely past conduct that has ceased.

## Conclusion

The court held that alleged hazardous waste contamination left on land by a prior lessee can support nuisance and trespass claims as continuing wrongs and may avoid dismissal on statute of limitations grounds at the pleading stage, while limiting unfair-competition relief where only past conduct is alleged.


Mangini v. Aerojet-General Corp., 230 Cal. App. 3d 1125 (Cal. Ct. App. 1991)