API Publ 4658:1997 pdf download

API Publ 4658:1997 pdf download.METHODS FOR MEASURING INDICATORS OF INTRINSIC BIOREMEDIATION: GUIDANCE MANUAL.
Site data on geochemical indicators of intrinsic bioremediation can be used in a variety of ways, ranging from very qualitative uses (e.g., comparison to background data) to very quantitative uses (e.g., input parameters to numerical fate and transport models). The ultimate data use dictates the data quality objectives. The data quality that can be expected from the various sampling and analytical methods and impacts on data use, are discussed in this report. This report should not be interpreted as providing endorsement of any particular data use.
This guidance document focuses on collection of representative intrinsic bioremediation data at petroleum hydrocarbon sites, However, the observations and findings presented here will generally be applicable to any site where biodegradable organic constituents occur.
REPORT ORGANIZATION
This report is organized in four sections.
1. Introduction to report purpose and organization..
2. Overview of sampling and method selection. Information is presented on how sampling and analytical methodology can affect intrinsic bioremediation data. The general factors that should be considered in selecting sampling and analytical methods are reviewed.
3. Discussion of sampling methodology. Four different groundwater sampling methods are described. The manner in which the sampling method may affect data quality is discussed, advantages and disadvantages of the methods are presented, and
This section presents an overview of the key considerations in sampling and analytical methodology. Information is presented on how sampling and analytical methodology can alter data on geochemical indicators of intrinsic remediation. The general factors that should be considered in selecting sampling and analytical methods are reviewed.
WHY BE CONCERNED WiTH SAMPLING AND ANALYTiCAL METHODOLOGY?
The characterization of key geochemical parameters of groundwater is a tool that has emerged in recent years for evaluating intrinsic bioremediation. Microbial metabolism of petroleum hydrocarbons has predictable geochemical consequences (Wilson et iii., 1994). For example. respiration of hydrocarbons may result in the loss of oxygen. nitrate, and sulfate, and the conversion of irOn from the femc to ferrous oxidation state. Petroleum hydrocarbons may also be biodegraded by an anaerobic process that results in the production of methane (i.e., methanogenesis). Measuring the trends in the distribution and concentration of these and other parameters can help to qualitatively establish hydrocarbon biodegradation activity. Data on the spatial distribution of these parameters, together with hydrogeologic and stoichiometric data, are also sometimes used to support the quantitative estimation of contaminant biodegradation rates and the prediction of plume migration.