Alternative Angles
A Study on Penetration Level of Nano Particles through Commercially Available Masks
Paper Presentation in a Themed Session Aniruddha Mitra
The concentration of airborne particle near a construction site has been a prime focus of the researchers. However, the data on nanosized particles are very limited, primarily due to lack of availability and cost involved. Nonetheless, nanosize particles are comparatively more harmful to humans. In this study, the focus has been on the concentration of nanosized particles at various distances from several active construction sites. Part of the investigation was also to estimate the effect of construction-related activities to humans who were not directly involved with the activities but in the vicinity. TSI NanoScan SMPS Model 3910 was used for our research. This instrument was able to count particles ranging from 10 nm to 400 nm size distributing them into thirteen different bin counters based on their sizes in a logarithmic scale. The measurements were taken at certain distances from the active spots, 5m, 10m, 15m and 30m. Three different sites were measured with different construction related activities; concrete work, demolition, woodwork. Uncontrolled parameters were temperature, humidity and wind speed and direction. For each site a control measurement was taken further away from the construction zone. Ten samples were taken for each measurement. Data ranged from statistically insignificant amount to an average of 2200 per cubic centimeter depending on the size of the nanoparticles and the location it was measured. With so many factors involved the validity of proposed model is subject to further investigations.
Impact Assessment, Irreducible Uncertainty, and Scenario Development
Paper Presentation in a Themed Session Peter Mulvihill
Scenario development is increasingly recognized as a potentially valuable technique in environmental impact assessment (EIA) processes, particularly in cases characterized by high levels of uncertainty. This paper explores past, present, and potential future applications for scenario techniques in EIA and related environmental planning and management processes. Barriers and constraints to increased use of scenarios are explored and possible solutions are proposed.
Constructing an Efficient Process: Time Studies at Tennessee Valley Authority’s Norris Dam Project, 1934-1936
Paper Presentation in a Themed Session Tracy Walker Moir-McClean
Construction of high dams requires complex coordination of human labor, natural resource extraction, and landscape alterations over time. This paper explores the means and impacts of construction timeline acceleration for a high profile New Deal Era project, the Tennessee Valley Authority’s (TVA) Norris Dam. Fast-tracking of ‘The Norris Project’ generated a politically critical flow of positive public-relation materials during the two years prior to Franklin D. Roosevelt’s 1936 re-election campaign (from ‘July 17, 1934 to June 1936’ p275 The Norris Report). To achieve this timeline, TVA staff reverse-engineered cement, aggregate, and concrete transport, handling, mixing, and placement, as well as resource extraction and processing workflows from previous Army Corp of Engineers projects they worked on— Madden Dam, Panama Canal Zone and Boulder (Hoover) Dam, Nevada USA. Labor, material and production targets developed in this exercise were implemented at the Norris Project using four daily work shifts. Norris managers then used methods similar to those described in Frederick Winslow Taylor’s The Principles of Scientific Management to identify time-inefficiencies. Iterative adjustment and time-testing of workflows continued until both speed of production and quality of concrete were effectively maximized. Interesting facets of ‘The Norris Project’ include on-site quarrying and processing of aggregates and sand, and pursuit of extreme time-efficiency. References include TVA reports and archive materials, as well as the considerable literature available on modern-era time-management. Given format constraints, address of social and environmental consequences of timeline acceleration are minimized, however the author welcomes inclusion of these concerns in post-presentation discussion.
