Brazilian police launched a probe last week to investigate an offshore oil spill in a field operated by Chevron Corp. Brazil's energy agency attributed oil seeps off the coast of Rio de Janeiro to a spill at the company's Fade site, where Chevron estimates that as much as 650 barrels of oil was creating a sheen on the surface. Some environmental groups claim that the spill is much larger, and Fabio Scliar, head of the federal police's environmental affairs division, said that information provided by Chevron did not match reports from technicians.

Brazilian Amazon deforestation fell to the lowest level ever reported, but progress may be shortlived as the Senate voted to ease rules for farmer forest preservation. The bill, an update to a 1965 law that severely restricted the amount of land farmers can clear, revises the 55 million hectares that farmers would have to restore to 24 million hectares. And while the Senate revised a lower house measure that would have provided amnesty for illegal deforestation before 2008, farmers will not have to pay billions of dollars in fines. Instead, they will have time to allow regeneration.

Brazilian federal prosecutors have filed a civil suit against Chevron and Transocean seeking $10.6 billion from Chevron and aiming to suspend both companies from operating in the country. The suit is in response to a leak in November at Chevron's Fade site, which, according to a statement from the prosecutor's office, demonstrated a lack of planning and environmental management by the companies. Chevron responded that the spill was halted in four days with minimal damage to the environment.

Deforestation may cause the Amazon Basin to become a net emitter of carbon dioxide, according to a study published in the journal Nature. Though the region has traditionally defended against climate change, the basin's large population growth over the last 50 years has caused a massive spike in clearing for logging and agriculture. The study estimates that the Amazon contains 100 billion tons of carbon in its biomass, which is gradually released as the forest is cleared.

Though Petrobras appears to have contained Brazil's second major oil spill in four months, the accident has raised questions about offshore drilling's safety as the country moves forward with plans to develop offshore resources. A government team evaluating efforts to contain the spill said that there was virtually no chance the oil would reach the coastline, and that Petrobras' quick response was able to control the spill. However, environmental regulators have questioned the company's emergency plans.

Chevron's oil license is at risk in Brazil after federal prosecutors filed criminal charges against executives for an oil leak near Rio de Janeiro last year. Federal Prosecutor Eduardo Santos de Oliveira charged 17 Chevron and Transocean executives with environmental crimes and called for prison sentences of up to 31 years, adding to an earlier civil lawsuit seeking over $11 billion in damages. Oliveira has said that Chevron's drilling damaged the subsea reservoir, creating a "contamination time bomb" and raising the possibility of catastrophic future leaks.

The Brazilian Institute of Environment and Renewable Natural Resources (IBAMA), the nation's environmental agency, announced a "zero deforestation policy" last Wednesday in response to growing deforestation. Satellite images recently released by Brazil's space research institute suggest that deforestation from March to April 2011 increased sixfold over the same period last year. Last December, a study indicated that deforestation in Brazil was at its lowest level in 22 years. However, the recently released data shows a 27 percent spike.

Brazilian officials announced last week that the government would seek $1.2 billion in fines against over a dozen companies being investigated for buying beef from farms illegally deforesting or engaging in slave labor. The complaint also implicated Brazil's Institute for the Environment, which was accused of failing to supervise the companies. However, while Brazil has managed to reduce levels of deforestation by 70 percent since 2004, other areas of Brazil may have borne the brunt of the switch away from using deforested areas as grazing lands for livestock.

The Brazilian state oil company Petrobras will soon begin the process of carbon sequestration in its Lula oil fields to reduce the environmental impact of its deep water exploration. The oil fields, in the region known as the subsalt, contain large amounts of carbon dioxide (CO2) that will now be re-injected into oil reservoirs or sub-sea salt caverns rather than released into the atmosphere. "CO2 re-injection is common in the industry, but it is not common offshore and certainly not at this depth and pressure," said Petrobras engineer Rivadavia Freitas.

A Brazilian court lifted an order stopping construction of the controversial Belo Monte hydroelectric plant on Thursday. The plant, which will be the world's third largest hydroelectric dam, is to be built in the Amazon rainforest, but a federal judge ordered construction suspended in February on the grounds that certain necessary environmental provisions had not yet been met. The dam has been met with heavy criticism due to its possible effects on wildlife and its potential impact on indigenous people around the Xingu river.