LNAPL Impacted Groundwater
We remediate chemically affected soil and groundwater using a wide range of in-situ and ex-situ technologies. Our focus is to design, build, operate and support systems that are environmentally friendly, reliable, unobtrusive, and effective in restoring sites impacted by regulated and emerging contaminants. These chemicals often include, but are not limited to: volatile organic compounds (VOCs) such as tetrachloroethene (PCE), trichloroethene (TCE) which are known carcinogens and used as industrial cleaners and degreasers. Other toxic chemicals in the environment originate from gasoline, which contains benzene, toluene, ethylbenzene, and xylenes (BTEX). Some gasolines released into the environment contain oxygenates, most commonly methyl-ter-butyl ether (MtBE) which is regulated, along with its degradation byproduct tertiary butyl alcohol (TBA). We have remediated sites with light non-aqueous phase liquid (LNAPL), and dense-non-aqueous phase liquid (DNAPL).
Our work remediating manufacturing and chemical sites includes remediation of soil and groundwater affected with hexavalent chromium; we often encounter arsenic and naturally occurring selenium. Several industrial sites are affected with 1,4-dioxane which was commonly used to stabilize PCE and TCE.
We have worked on sites affected with inorganic compounds such as nitrates which commonly originate from wastewater treatment plants, and perchlorate (a propelant) which is a known endocrine disruptor.
During remediation, we implement monitoring plans to monitor effectiveness, we asess risks to human-health and the environment around the site, and support the process through regulatory closure.
The site remediation is often simple when it involves limited work such as tank removals; however, the process becomes increasingly complicated when potent carcinogens are detected, and when their distribution extends beyond the boundaries of the site, or if there are potential sensitive receptors. In all cases the responsible party works with a regulator and a consultant. All three sides negotiate and agree on the remedial approach that must be defensible to third parties and the public. We support site remediation through the following:
- Regulatory support.
- Environmental investigations of soil, soil gas, and groundwater.
- Feasibility studies and selection of a remedial approach.
- Bench-scale testing and pilot testing when required or applicable.
- Interim Remedial Action Plans.
- Remedial action plans and permitting with lead regulatory agencies, cities, and counties.
- Remediation system design and permitting.
- Support obtaining California Environmental Quality Act (CEQA) negative declarations.
- Remediation system construction and startup.
- Operator training.
- Construction documents such as operation plans, operation manuals, and as-built plans.
- Cost estimates to support project budgeting and financial assurance.
- Remediation system operation and maintenance.
- Support with health-risk assessments.
- Implementation of monitored natural attenuation.
- Remediation progress reports and discharge reports.
- Regulatory site closure.
- Permitting demobilization, demolition of equipment, and decommissioning wells.
- Support in processing land use restrictions.