摘要 |
A storm water and septic system using plastic galleries that have multiple layers provided having differing hardness characteristics, the exterior layer having a lower hardness rating than an inner layer; and a multi-layer gallery where the inner layer is treated to be resistance to degradation to a selected chemical that would otherwise degrade polyethylene. The gallery may further be provided with an interior layer having defined dielectric properties such that a fluid level measurement can be made of fluid in the galleries.
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