Electricity requirements for sawmill operation (6.2E-03 kWh per pound of wood) and

recycling of steel (2.1 kWh per pound of recycled steel) were also accounted for, as

shown in Table 3-3. It is important to note that, for every pound of salvaged wood, one

pound of virgin wood is avoided. Thus, the values provided in Table 3-3 represent

"savings" in relation to using all virgin materials in reconstruction applications, and their

resulting emissions will be considered as "emissions savings" rather than contributions.

 Emissions

 Tables 3-4, 3-5, 3-6 and 3-7 show the primary environmental emissions that result

from each of the four scenarios per square foot of barrack. The emissions shown in these

tables represent the second option where material salvaged is reused or recycled within

20 miles of the deconstruction site. Emissions from the other two options-no salvaging

or reuse and transportation of all reusable materials to Austin, TX-are considered in the

discussion of impact analysis results below. While the SimaPro modeling software

included hundreds of emissions from the included life cycle stages, only those in highest

quantity and/or risk to the public and environment were considered. These emissions

have been broken down into four categories-criteria pollutants, greenhouse gases,

metals, and miscellaneous chemicals-which have been further separated by life cycle

stage, during salvaging of material (Stage 13 in Figure 3-2), disposal (Stages lb, 2a and

the waste from stages 3-12), use of equipment during deconstruction (Stages 3, 4 and 6-

12), and transport of equipment and labor to and from the site (Stage la). The emissions

with negative values in Tables 3-4, 3-5, 3-6 and 3-7 represent savings as a result of

replacing virgin materials with salvaged materials.

 The most highly emitted species from all four scenarios were carbon monoxide

(CO), carbon dioxide (C02), volatile organic compounds (VOCs), nitrogen oxides (NOx),