No abstract

A SCAT survey in 2002 documented conditions at 39 selected survey sites where EVOS oil persisted in 1992, at the time the Federal and State On-Scene Coordinators determined that further cleanup activities would provide no net environmental benefit. The 2002 field survey found isolated occurrences of residual EVOS surface oil (SO) in the form of weathered asphalt pavement at 15 of the 39 sites. SO, expressed as a continuous oil cover, was less 0.2% of the surface area surveyed. Seven of the 39 sites and 815 (68%) of the total 1182 pits contained no residual SSO. SSO was found primarily in middle to upper intertidal locations, where it occurred in discontinuous ∼3cm thick bands 5–10 cm below the boulder/cobble or pebble/gravel veneer. Despite evidence of continued oil weathering, both at the surface and in the subsurface, it is clear that the natural cleaning processes at these particular locations are slow. The continued but slow weathering rates are a consequence of the oil being sequestered from the environment because it occurs in mixed (coarse and fine) sediments on beaches where boulders and outcrops, shallow bedrock asperities, or boulder-armoring limit effective physical weathering action.

Concussions are becoming an increasingly important issue in sports, especially in an area like volleyball that, until recently, seemed less prone to such injuries. The purpose of this study was to determine the coefficient of restitution and basic mechanical properties of standardized volleyballs, including stiffness and hysteresis, dependent on different influencing factors. A drop test was performed to calculate the coefficient of restitution based on the time of flight of the ball between the first and second bounce. This was detected using a microphone with a sampling frequency of 44.1 kHz. To determine the mechanical properties, a materials testing machine applied a compression force until a deformation of 50 mm was achieved. These data were sampled with a frequency of 12.5 kHz. The results showed that the three analysed factors in this study, including the ball model, gauge pressure, and incident velocity, had a significant influence on the coefficient of restitution. Therefore, the amount of energy dissipation during an impact situation at low velocities was significantly different within the tested sample of official standardized volleyballs. The stiffness and hysteresis of the volleyballs also varied significantly. These basic mechanical findings raise an interesting question as to whether the investigated factors are appropriate to predict forces acting on the head during a high velocity collision (25-30 m/s), ultimately resulting in a risk of concussion.

# 1141233 The cargo of a double-tank truck carrying diesel and gasoline was released directly into a fast-flowing upland stream following an accident on a mountainous section of road in British Columbia (BC), Canada. High concentrations of the product were trapped in the interstitial spaces of coarse (cobble-boulder) sediments during a period of rising water levels. Almost the entire river backshore in the affected area was characterized by steep wooded slopes so that access everywhere was very difficult. These constraints for the SCAT program largely were overcome where direct backshore access was not possible using river rafts, boats (on the reservoir above the dam) and small Unmanned Aerial System (sUASs). Based on the survey results, a 4x4 Spider Walking Excavator equipped with a Universal grab on the hydraulic arm was deployed over a 2.5 km section of river immediately downstream of the accident site over a 9-day period. The grab rotated to mix the sediment or lifted and moved cobbles and boulders along the channel margin and in river bed sediments to release the oil. Swift Water Rescue personnel and river rescue response equipment were positioned with the Spider operations and the SCAT river bank surveys throughout the project, and used to scout river conditions ahead of SCAT rafting operations. Air monitoring was maintained throughout the response during all operations both along river banks as well as in the cab of the Spider while working in the river. A small UAS quadcopter was deployed to monitor the mixing activity in real time where the excavator could operate but ground access was unsafe or physically not possible. Standard SCAT practices were followed to provide the Unified Command (UC) with Shoreline Treatment Recommendation (STR) forms to guide the operations activities and once the treatment criteria were achieved STR Inspection Reports (SIRs) were submitted for approval by the UC. A downstream daily water sampling program monitored for PHs, VOCs and PAHs in the river waters during the mixing operations downstream of the operations area. At no time during the mechanical mixing activities (April 3 – 12) did the results of the analyses exceed Canadian and BC Water Quality Guidelines standards downstream past the confluence with the Salmo River and standards only were exceeded for the first few days of mechanical mixing (April 3 – April 5) during the period that the Spider was working on the upper reaches of the South Salmo.