The City of Socorro's long battle with arsenic-contaminated drinking water is coming to a head.

On Wednesday, Aug. 19, Camp Dresser & McKee Inc. Project Engineer Robert Fowlie led an hourlong arsenic project presentation followed by a 30-minute open forum for public input.

Fowlie discussed three types of arsenic treatment systems and gave examples of similar systems used in other communities. The goal of the proposed treatment system is to bring the city's arsenic level to within Environmental Protection Agency standards of 10 parts per billion.

The city's ongoing arsenic project includes implementing systems at the Socorro Springs, Industrial Park and City wells. Fowlie said his firm's primary concern was the impact on the community.

"We're trying to look for treatment processes that suit the community. The recommended process is low cost and lowers the arsenic level effectively," Fowlie said.

The trio of treatment technology options presented focused iron-based sorbents, coagulation and filtration with granular media and electroflocculation and filtration with granular media. The media used in these systems would be a combination of layers of sand and charcoal.

In a previous El Defensor Chieftain article, City Utilities Director Jay Santillanes compared the treatment process to a common filter used on a household water faucet. The firm recommended the city use the coagulation and filtration treatment because of its lowered cost over the 20-year life of the project.

The recommended treatment technology involves increasing the iron concentration in the water by adding ferric chloride. Once the iron levels have been increased the arsenic in the water adsorbs, or sticks, to the iron particle. Filter media is used to remove the iron and arsenic. This process creates a byproduct of water with a high arsenic content. The water is pumped out into backwash storage tanks, which allows the water to settle and the solids to be removed. Once the solids are removed they are sent to dry on drying beds. When the solids are dry enough they can be hauled to the landfill.

Fowlie assured the audience that the system would be carefully monitored.

"The arsenic levels will be monitored on a daily and weekly basis," he said. "Appropriate adjustments will be made with the chemicals used in the treatment process."

In a separate interview, Fowlie confirmed that the solids are required to pass the Toxicity Characteristics Leaching Procedure test in order to verify that the arsenic will not leach out of the solids and recontaminate ground water. Fowlie estimated that the two treatment facilities will generate an estimated combined total of 75 pounds of dry solids per day.

"The solids are stored in drying beds that are designed to be emptied every 90 days," he explained.

In order to address the concern with issues of space at the landfill, Mayor Ravi Bhasker said the city has been dumping sludge from the city sewer system without any problems.

The city has designed and implemented a pilot arsenic treatment facility at the Socorro Springs Well. The facility is designed to use the recommended coagulation and filtration treatment system. City workers spend hours experimenting with different settings on the system in order to determine what is the most effective procedure. The system supplies Socorro with approximately 30 percent of its water needs.

Also during Wednesday's meeting, Parametrix Inc. Project Manager Sarah Gilstrap presented the Environmental Information Document her firm had researched and compiled.

The city is in the process of obtaining funding to complete the project. Once appropriate funding is obtained, the project is scheduled to have all of the engineering design work completed by January 2010. Project construction is expected to begin in February 2010. Completion of the project is expected by early 2011. The total cost is $4.4 million, which includes engineering and land acquisition.

Residents have two weeks to contact Parametrix Inc. with questions or concerns about the project. Written comments can be mailed to Sarah Gilstrap at Parametrix Inc., 8901 Adams St. NE, Suite D, Albuquerque, NM 87113; faxed to 505-821-7131; or e-mailed to This e-mail address is being protected from spambots. You need JavaScript enabled to view it .