Title : Treatment of Balloons with DFA Type : Antarctic EAM NSF Org: OD / OPP Date : July 18, 1990 File : opp93007 DIVISION OF POLAR PROGRAMS OFFICE OF SAFETY, ENVIRONMENT AND HEALTH 202/357-7766 MEMORANDUM Date: July 18, 1990 From: Environmental Officer, DPP Subject: Environmental Action Memorandum on Treatment of Balloons with DFA at South Pole Station To: Files [S.7.1] On July 13, 1990, the Environmental Officer had a discussion on the abovementioned subject with the Program Managers for Polar Ocean and Climate Sciences and Polar Aeronomy and Astrophysics. We agreed that all uses of scientific research balloons within the U.S. Antarctic Program are categorically excluded from the environmental assessment process. Despite this exclusion, we all agreed that some explanation of why such balloons might need to be treated with DFA was appropriate. The balloons that are treated with DFA are latex rubber in composition, and they are used effectively without treatment during the austral summer months. Treatment with DFA is a necessity, at times, during the colder austral winter season as these latex rubber balloons are subject to rupture as they ascend. Treatment with DFA makes the latex rubber balloons more flexible and more able to reach expected altitudes (with consequent acquisition of valuable data). Another solution to the problem of latex rubber balloon rupture is being evaluated by the Program: use of polyethylene balloons (e.g., Raven 7K balloons). The polyethylene balloons have been shown to be more flexible at low temperatures and, therefore, less subject to rupture. They do require, however, more helium per balloon filling/launch than do latex rubber balloons, and they are not as degradable as latex rubber balloons. The added helium requirement is a significant fuel cost issue as the gas must be transported to stations in heavy cylinders. Consider- ation of the advantages and disadvantages of each balloon type continues. -2- FINDING During colder winter months, regular use of polyethylene balloons or limited use of DFA-treated balloons, appear to be justifiable means of obtaining valuable meteorologic or atmospheric data. The Environmental Engineer should advise Antarctic Support Associates of the findings of this memorandum. Sidney Draggan cc: Safety, Environment and Health Officer, DPP Environmental Engineer, DPP Science Projects Manager, DPP Program Manager, Polar Ocean and Climate Sciences, DPP Program Manager, Polar Aeronomy and Astrophysics, DPP