Quantification of hydrochloric acid and particulate deposition resulting from space shuttle launches at John F. Kennedy space center, Florida, USA

Abstract

Observations of damage to vegetation, acute reductions in surface water pH, and kills of small fish prompted the Biomedical Operations and Research Office at the John F. Kennedy Space Center to initiate intensive environmental evaluations of possible acute and long-term chronic impacts that may be produced by repeated launches of the space shuttle. An important step in this evaluation was the identification of deposition patterns and the quantification of ecosystem loading rates of exhaust constituents from the solid rocket motors (SRMs) in the area of the launch pad. These constituents are primarily aluminum oxide (AI2Q) and hydrochloric acid (HCI). During three launches of the space transportation system 13, and 14) up to 100 bulk deposition collectors, 83 mm in diameter containing 100 ml of deionized water, were deployed in a grid pattern covering 12.6 ha north of launch pad 39-A. Estimates of HCI and particulate deposition levels were made based on laboratory measurements of items entrained in the collectors. Captured particulates consisted of a variety of items including AI203, sand grains, sea shell fragments, paint chips, and other debris ablated from the launch pad surface by the initial thrust of the SRMs. Estimated ranges of HCI and particulate deposition in the study area were 0-127 g/m 2 and 0-246 g/m 2, respectively. Deposition patterns were highly influenced by wind speed and direction. These measurements indicate that, under certain meteorological conditions, up to 7.1 x 103 kg of particulates and 3.4 x 103 kg of HCI can be deposited to the near-field environment beyond the launch pad perimeter fence.

Atmospheric deposition of elements and its relevance for nutrient budgets of tropical forests

“…The combustion of ammonium perchlorate results in the production of water, dioxygen, dinitrogen and hydrogen chloride. Hydrogen chloride is found primarily in gaseous form at room temperatures and above (Breuer 2002) and can thus be deposited over a large area in the days and weeks following the launch, as was shown at the John F. Kennedy space centre, USA (Dreschel and Hall 1990). This may explain the high non-sea-salt fraction and deposition of Cl -, which is more than five times higher than observed at other tropical sites, many of which are situated near the coast (Vet et al 2014).…”

The sky is falling: Chemical characterization and corrosion evaluation of deposition produced during the static testing of solid rocket motors

“…As the cloud cools, the deposition material, referred to as Test Fire Soil (TFS), drops on the surrounding area (usually at a 10-20°angle that extends out to 10-12 miles) that includes rangeland, farmland, low-density residential housing and several wildlife management areas. Due to its exposure to elevated temperatures (combustion gas temperatures approach 6000°F) and combustion products (largely aluminum oxide and hydrogen chloride [Dreschel and Hall, 1990]), the composition of the Test Fire Soil (TFS) is expected to be different from the native soil.…”

“…The monitoring conducted during several past Space Shuttle launches and vertically restrained static rocket motor tests having similar fuel composition provides some pertinent information on the potential constituents and impact of the deposition material generated during the static tests. The typical RSRM used in the Space Shuttle program contained over 500,000 kg of a composite propellant comprised of an ammonium perchlorate oxidizer (70%), an aluminum powder fuel (16%), a polybutadiene-acrylic acid-acrylonitrile terpolymer (PBAN) binder (12%), an epoxy curing agent (2%), and a catalyst of iron oxide powder (0.1%) (Dreschel and Hall, 1990). The main exhaust products were aluminum oxide Al 2 O 3 (30%), carbon monoxide CO (23%), hydrogen chloride HCl (22%), water (10%), and nitrogen (8%) (Dreschel and Hall, 1990).…”

“…The typical RSRM used in the Space Shuttle program contained over 500,000 kg of a composite propellant comprised of an ammonium perchlorate oxidizer (70%), an aluminum powder fuel (16%), a polybutadiene-acrylic acid-acrylonitrile terpolymer (PBAN) binder (12%), an epoxy curing agent (2%), and a catalyst of iron oxide powder (0.1%) (Dreschel and Hall, 1990). The main exhaust products were aluminum oxide Al 2 O 3 (30%), carbon monoxide CO (23%), hydrogen chloride HCl (22%), water (10%), and nitrogen (8%) (Dreschel and Hall, 1990). Hydrochloric acid is formed when the HCl gas dissolves in the water produced during combustion and the existing atmospheric water vapor (humidity).…”

“…Hydrochloric acid is formed when the HCl gas dissolves in the water produced during combustion and the existing atmospheric water vapor (humidity). From the bulk deposition collectors used during three shuttle launches at the Kennedy Space Center in Florida USA, Dreschel and Hall (1990) estimated HCl and Al 2 O 3 depositions to range from 0 to 127 g/m 2 and 0 to 246 g/m 2 , respectively. The deposition was highly influenced by wind speed and direction and led to short-term decreases in soil and water pH surrounding the Kennedy Space Center after shuttle launches.…”