impact environmental

Phase III Environmental Site Assessments (ESAs) and Remedial Investigation/Feasibility Studies

PHASE III ENVIRONMENTAL SITE ASSESSMENTS
A Phase II Environmental Site Assessment (ESA) that detects the presence of contaminants is followed by a Phase III Environmental Site Assessment. A Phase III ESA is performed to determine the nature and extent of the contamination, and to classify the impacted media detected materials in accordance with Local, State, and Federal codes, rules and regulations for disposal.

Contaminated materials are divided into two categories for subsequent treatment and disposal: hazardous and non-hazardous. Hazardous materials are defined as all those materials listed as "hazardous" pursuant to Local, State, or Federal codes, or those materials displaying the characteristics of a hazardous material. These characteristics are based on laboratory analysis for ignitability, corrosivity, reactivity, and toxicity. All contaminated materials not defined as hazardous are generally regarded as non-hazardous solid waste.

The classification of a particular waste stream is essential for determining proper waste disposal options which may include landfilling, incineration, and recycling.

All projects handled by Impact Environmental involving the extraction, transportation, and/or disposal of contaminated materials are supervised by qualified individuals. These individuals include certified geologists, engineers, and biologists.

Impact Environmental provides clients with a detailed report documenting compliance with all applicable codes. Accordingly, liability is reduced and/or eliminated.

REMEDIAL INVESTIGATION/FEASIBILITY STUDIES
Remedial Investigation/Feasibility Studies (RI/FS) are integral toward defining the nature and extent of contaminants at State or Federal Hazardous Waste Disposal Sites. Designed and executed properly, and RI/FS can be used to justify a risk-based "no further action" decision or a limited corrective action alternative to regulators. Impact Environmental has performed RI/FS activities at over 15 Inactive Hazardous Waste Disposal Sites in the Tri-State Area. Working within the parameters of the New York State Department of Environmental Conservation (NYSDEC) Division of Hazardous Waste Remediation's Voluntary Cleanup Program, Impact Environmental has routinely found responsible and cost effective ways to attain site closure.

The following are the regulatory limits for a hazardous material under the Toxicity Characteristic Leaching Procedure (TCLP). TCLP analysis is commonly performed on media for Phase III Assessments.

VOLATILE COMPOUNDS
Parameter	Hazardous Limit*
Benzene	0.5
Carbon Tetrachloride	0.5
Chlorobenzene	100
Chloroform	6
1,2 Dichloroethane	0.5
1,1 Dichloroethylene	0.7
Methyl ethyl ketone	200
Tetrachloroethylene	0.7
Trichloroethylene	0.5
Vinyl Chloride	0.2

SEMI-VOLATILE COMPOUNDS
Parameter	Hazardous Limit*
o-Cresol	200
m-Cresol	200
p-Cresol	200
1,4 Dichlorobenzene	7.5
2,4 Dinitrotoluene	0.13
Hexachlorobenzene	0.13
Hexachlorobutadiene	0.5
Hexachloroethane	3
Nitrobenzene	2
Pentachlorophenol	100
Pyridine	5
2,4,5-Trichlorophenol	400
2,4,6-Trichlorophenol	2

PESTICIDES/HERBICIDES
Parameter	Hazardous Limit*
Chlordane	0.03
Endrin	0.02
Methoxychlor	10
Toxaphene	0.5
Heptachlor (and its hydroxide)	0.008
2,4-D	10
2,4,5-TP (Silvex)	1

METALS
Parameter	Hazardous Limit*
Arsenic	5
Barium	100
Cadmium	1
Chromium	5
Lead	5
Mercury	0.2
Selenium	1
Silver	5

* mg/L = parts per million (PPM)