8.4.1 How ISM Is Being Conducted


ISM sampling has been used nearly twice as frequently on sites with commercial/industrial land use as compared with residential land use. When queried about the programs in which ISM sampling was most often conducted, survey respondents identified CERCLA and state-lead cleanup sites most frequently, followed by RCRA and petroleum sites (see Figure 8-2).

Survey response of ISM sampling in land use type by program

Figure 8-2. Survey response of ISM sampling in land use type by program.

According to the survey responses, ISM is being used primarily during screening investigations or to obtain data for meeting regulatory or cleanup criteria (see Figure 8-3) and primarily on surface soils (see Figure 8-4). Fewer than half of the respondents indicated they had used ISM for subsurface soil sampling. Very few respondents cited use of ISM for other matrices, such as sediment, soil gas, and water.

Survey responses identifying the objectives of ISM sampling.

Figure 8-3. Survey responses identifying the objectives of ISM sampling.

Survey responses of the ISM media applications.

Figure 8-4. Survey responses of the ISM media applications.

ISM has been used primarily to assess heavy metals and explosive residues. Other contaminants cited less frequently include VOC and SVOCs, PCBs, and total petroleum hydrocarbons (TPH).

Hawaii, California, and Alaska together account for more than 40% of all ISM sampling activity.

Although survey data show ISM has been conducted in 36 states, over half of the ISM sampling activity has been conducted in a relatively small number of states, with Hawaii, California, and Alaska together accounting for over 40% of all ISM sampling activity (see Figure 8-5). The survey found that about half of the ISM sampling projects have been conducted on commercial/industrial land use types (see Figure 8-6).

Figure 8-5. Survey responses of states where the organization has participated in ISM.

Survey responses of ISM sampling participation per land use type.

Figure 8-6. Survey responses of ISM sampling participation per land use type.