Costs And Benefits Of Mitigating Radon In Drinking Water
The Environmental Protection Agency (EPA) is considering regulating radon, a naturally occurring soil gas dissolved in drinking water, because it poses a lung cancer risk. Benefits and costs of compliance are estimated for 29 water systems with radon above the proposed maximum contaminant level. The estimated cancer risk is three times higher than assumed by EPA, making it likely that a national regulatory standard of 300 picocuries per liter of water would pass a cost-benefit test. Site specific estimates of compliance costs are also substantially greater than EPA estimates. Nevertheless, the estimated cost per avoided death is only about $1 million.
Seasonal variation on radon emission from soil and water
Radon is being measured continuously in spring water and soil-gas at Badshahi Thaul Campus, Tehri Garhwal in Himalayan region by using radon Emanometer since December 2002. An effort was made to correlate the variance of radon concentrations in spring water and soil-gas with meteorological parameters at the same location. The main meteorological parameters that affect the radon emanation from host material is surrounding temperature, barometric pressure, wind velocity, rain fall and water level of the spring. The correlation coefficient between radon concentration in spring water and different atmospheric parameters was computed. The correlation coefficient between radon concentration in spring water and the maximum atmospheric temperature was 0.3, while it was 0.4 for minimum atmospheric temperature at the monitoring site. The correlation coefficient for radon concentration in spring water with minimum and maximum relative humidity was 0.4. Spring water radon concentration was found positively correlated (0.6) with water discharge rate of the spring. A weak correlation (0.09) was observed between the radon concentration in spring water and rain fall during the measurement period. As temperature of near surface soil increases, the radon emanation coefficient from the soil surface also increases. The possible effects due to global warming and other climatic changes on environment radiation level were also discussed in detail.
"The Plain Round Tale of Faithful Thady": Castle Rackrent as Slave Narrative
Critics of Maria Edgeworth’s Castle Rackrent tend to focus on textual elements—gender issues, the symbolism of the Big House, colonial hegemony— or contextual readings by placing Edgeworth in the Anglo-Irish history and tradition. While such criticism usually in some way examines the main theme of the text, the appropriation of power and authority, little of it accomplishes both the textual and contextual analysis that Castle Rackrent deserves. Exploring Thady’s “plain round tale” as a slave narrative in content and form sheds new light on the work both textually and contextually; in Thady Quirk, Edgeworth has created a typical slave narrator who recounts a history of oppression which is ultimately mediated by an outside editor. As John Cronin writes of Castle Rackrent, “What Maria Edgeworth has given us . . . is a magnificently realised slave, a terrifying vision of the results of colonial misrule. There must have been a moment of clearly deliberate artistic decision in which she realised that what needed to be said must be said through one of the submerged people.”1 The three main textual elements of the narrative indicate its likeness to typical slave narratives: its presentation of a conflicted slave narrator, its use of the framing device of the outside editor, and its narrative structure of episodic anecdotes that utilizes memory, description, and didacticism.