Database Statistics

Reliability. There has been a significant rise in interest among pump users in the 1990s to improve equipment reflabiUty and increase mean time between failures. Quantifiable solutions to such problems are being sought (61). Statistical databases (qv) have grown, improved by continuous contributions of both pump manufacturers and users. Users have also learned to compile and interpret these data. Moreover, sophisticated instmmentation has become available. Examples are vibration analysis and pump diagnostics. 

Subject Categories. The deterrninant for user selection of a database is usually subject matter. That is, when chemical information is desired, a chemical database is selected. The form or media of the database is of secondary importance. The type of search may dictate the need for a full-text or statistical database. If none exists, however, a bibhographic database in the topic area may be used to locate full-text or numeric compilations in hard-copy form. 

CLPSD. 1989. Contract Laboratory Program Statistical Database. U.S. Environmental Protection Agency. July 12, 1989. 

Another source of acrylonitrile in water is leachate from chemical waste sites. Preliminary data from the Contact Laboratory Program (CLP) Statistical Database indicates that acrylonitrile has been detected in surface water samples collected at two of 862 hazardous-waste sites (including NPL and other sites) being investigated under Superfund. The median concentration of the positive samples was 100 pg/L (CLPSD 1988). Acrylonitrile was detected in 12 groundwater samples collected at 5 sites, also at a median concentration of 100 pg/L. 

FAO (1982) Village forestry inventory in Bangladesh Project findings and recommendations. United nation development programme. Food and Agriculture Organization of the United Nations, p 25 FAO (2005) FAO statistics database, October 2005... 

UNSD (United Nations Statistics Division) (2007). Statistical Databases (Common Databases). Online database, http //unstats.un.org/unsd/databases.htm. 

Dibromoethane has been detected in an estimated 0.23% of the groundwater samples analyzed for the 2,783 hazardous waste sites participating in the Contract Laboratory Program (CLP) a positive geometric mean concentration value was not reported. 1,2-Dibromoethane has not been detected in surface water samples taken at hazardous waste sites (CLPSD 1988). Note that the CLP Statistical Database (CLPSD) includes data from both NPL and non-NPL sites. 

Heptachlor has been detected in an estimated 1.4% of the groundwater samples taken at NPL hazardous waste sites included in EPA s Contract Laboratory Program (CLP) at an estimated geometric mean concentration of 0.78 ppb for the positive samples (CLPSD 1989). The compound was not listed in the CLP Statistical Database (CLPSD) of chemicals detected in surface water samples collected at NPL sites. Heptachlor epoxide was not listed in the CLPSD of chemicals detected in groundwater or surface water samples collected at NPL sites. Note that the information from the CLPSD includes data from NPL sites only. 

Hall et al. (1985) reported that no 1,2-diphenylhydrazine (less than pg/L) was detected in the Nanticoke River near the Chesapeake Bay. The analytical method involved liquid-liquid extraction, concentration, and. analysis by GC/MS. The Contract Laboratory Program statistical database (queried April 13, 1987) reported that 1 2-diphenylhydrazine has been detected n water at i of 357 hazardous waste sites at a concentration of (96 ppb (CLPSDB 1987), and has been reported at 7 of 117, sites. n the national Priority List database (ATSDR 1990) The U.S. EPA Contract laboratory Program uses GC methods to analyze the contaminants of interest. Since 1,2-diphenylhydrazine oxidize, to azobenzene in the GC injector port and both 1,2-diphenylhydrazine and azobenzene, have the same GC retention time and mass spectra, reports of 1,2-diphenylhydrazine from the Contract Laboratory Program may actually represent detections of 1,2-diphenylhydrazine, azobenzene, or both (see Chapter 6 for more details). 

Diphenylhydrazine has been identified in soil only at hazardous waste sites. The Contract Laboratory Program statistical database (queried April 13, 1987) reported that 1,2-diphenylhydrazine has been detected in the soil at 2 of 357 hazardous waste sites in both cases at 18,200 ppm (CLPSDB 1987). The Contract Laboratory Program uses GC methods to analyze the contaminants of interest. As discussed in Section 5.4.2, this may actually represent detections of either... 

CLPSD. 1988. Contract laboratory program statistical database. Viar and Company. Alexanderia,... 

Hexanone has been detected in both surface water and groundwater at hazardous waste sites. Data from the Contract Laboratory Program (CLP) Statistical Database indicate that 2-hexanone was found at 2% of the sites at a geometric mean concentration of 7.5 pg/L (ppb) in positive surface water samples and 12 pg/L (ppb) in positive groundwater samples (CLPSD 1989). This database provides data from both NPL and non-NPL waste sites. 

WHO. 2002. Health for All Statistical Database. European Public Health Information Network for Eastern Europe. World Health Organization. http //www.euphin.dk/hfa/Phfa.asp. 

FAOSTAT, FAO Statistical Databases, Fisheries Data (2001). Food and Agriculture Organization of the United Nations, Rome, Italy, http //www.fao.org. Available from Internet, URL. 

Dichloromethane has been detected in both surface water and groundwater samples taken at hazardous waste sites. Data from the Contract Laboratory Program Statistical Database of the United States Environmental Protection Agency indicate that dichloromethane was present at geometric mean concentrations of 68 and 98 pg/L in surface water and groundwater samples, respectively, at about 30% of the sites sampled (Agency for Toxic Substances and Disease Registry, 1993). 

According to the VIEW Database (1989), silver has been found at 27 sites on the National Priority List of 1,177 sites. The frequency of these sites within the United States can be seen in Figure 5-1. EPA s Contract Laboratory Program (CLP) statistical database indicates that silver has been detected at 100% of the 2,783 Superfund hazardous waste sites that have had samples of all media analyzed by the CLP (CLP 1988). 

Silver has been detected with a geometric mean concentration of 6.0 pg/L in groundwater samples from 613 of the 2,783 (22%) hazardous waste sites included in EPA s Contract Laboratory Program (CLP) statistical database (CLP 1988). It has also been detected in surface water samples from 552 of the 2,783 (20%) sites in the CLP statistical database with a geometric mean concentration of 9.0 pg/L (CLP 1988). 

The deviation scenarios found in the previous step of the risk analysis must be assessed in terms of risk, which consists of assigning a level of severity and probability of occurrence to each scenario. This assessment is qualitative or semi-quantitative, but rarely quantitative, since a quantitative assessment requires a statistical database on failure frequency, which is difficult to obtain for the fine chemicals industry with such a huge diversity of processes. The severity is clearly linked to the consequences of the scenario or to the extent of possible damage. It may be assessed using different points of view, such as the impact on humans, the environment, property, the business continuity, or the company s reputation. Table 1.4 gives an example of such a set of criteria. In order to allow for a correct assessment, it is essential to describe the scenarios with all their consequences. This is often a demanding task for the team, which must interpret the available data in order to work out the consequences of a scenario, together with its chain of events. 

Barium has been detected with a positive geometric mean concentration of 101.6 mg/L in groundwater samples from approximately 58% of the 2,783 hazardous waste sites that have had samples analyzed by the Contract Laboratory Program (CLP) (CLPSD 1989). Barium has also been detected with a positive geometric mean of 62.6 mg/L in surface water samples from 27% of the sites in the CLP statistical database (CLPSD) represent frequency of occurrence and concentration information for NPL sites only. 

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