Slot Anti Rungkad

Water woes: Columbia’s water treatment plant is getting a makeover. Some argue it won't make the water safer to drink | Local - Energy And Water Development Corp

Water woes: Columbia’s water treatment plant is getting a makeover. Some argue it won’t make the water safer to drink | Local

Early this year, the city will be looking for bidders to tackle a project that will affect just about everyone in Columbia.

The facility supplies water to the taps of more than 115,000 Columbia residents, and replacing the half-century-old, expired equipment is a cause for celebration for the department. Under the renovation plan, the facility will install new aerators, upgrade treatment capacity and achieve more efficient plant operations.

A contract awarded early this year will set the construction price tag and timeline.

But some residents aren’t happy about it. They say it’s not enough to upgrade the old equipment — only a change in the water treatment process itself will deliver better-quality water to Columbia customers.

Julie Ryan and Marie Brown, co-founders of the COMO Safe Water Coalition, have been crusading for cleaner drinking water in Columbia for years. Go to any city meeting on the subject, and you’re likely to spot them vigorously taking notes on the presentation.

The pair know all about the upcoming project at the water treatment plant, and they’re exasperated.

“We are paying for repairs that should have been done over a decade ago,” Ryan said in a pointed address to the Columbia City Council in November. “We’re not getting the true water quality accomplishments that we should.”

A longtime stance of the advocates has been their vehement opposition to the process of chemical disinfection used at the plant. Even with the upgrades, a change in the treatment process isn’t part of the city’s plan.

Years ago, Columbia’s water was treated with chlorine to remove harmful pathogens. Organic carbon in water contains microorganisms such as bacteria and other microbes that humans shouldn’t drink, and a chemical disinfectant like chlorine is added to keep them out.

Understanding chloramine only takes a quick chemistry lesson: It’s a chemical compound made with chlorine and ammonia. The result — chloramine — is considered to be better than chlorine at eliminating certain cancer-causing disinfection byproducts such as trihalomethanes or chemicals created when mixing chlorine and organic materials.

And yet, chloramine is not a risk-free solution.

Although the amount of ammonia added to the water is minuscule — “similar to adding six grains of table salt to a one-gallon container of water,” according to the city utility’s website — water treatment studies have found that chloramine can still react with organic matter in water to form dangerous byproducts.

Experts have found that chloramination can cause byproducts to develop that are not regulated by the EPA — and there are a lot of them. More than 700 disinfection byproducts have been discovered in drinking water. The EPA only regulates 11.

Experts fear that many unregulated byproducts, some classified as carcinogens, are left in the water after the disinfection process.

What’s in Columbia’s water?

In November, the Environmental Working Group, a research-based nonprofit watchdog, updated its database of American drinking water contaminants. The group has extremely strict standards for contaminants compared to legal limits: Disinfection byproducts like trihalomethanes and haloacetic acids in the city’s water were rated hundreds of times higher by the group’s toxicologists than they should be, despite being well within legal limits.

“Legal does not necessarily equal safe,” the site reported, noting that two decades have passed since the last update to tap water standards.

The rates of total trihalomethanes and haloacetic acids in the water were especially high for a plant that uses chloramination, a process meant to do a better job than chlorine at reducing such byproducts.

Total trihalomethanes were reported at 41.9 parts per billion, and the five regulated haloacetic acids were reported at 19 parts per billion. Legal limits are currently 80 and 60, respectively.

For a chloramination plant, “that’s crazy high,” Susan Richardson, a professor of chemistry and biochemistry at the University of South Carolina and an expert on disinfection byproducts, said after studying the data for Columbia’s water. She based her assessment on the relatively low levels of total organic carbon in the source water that the plant takes in through its wells.

Shawn Carrico, an engineering supervisor for Water and Light, doesn’t agree.

“On the surface, I don’t feel that’s an accurate statement,” he said. “It may be, I just don’t know without looking at the data and looking at other plants. … There’s too many things that contribute to disinfection byproducts.”

But the contents of city water that aren’t regulated could be of even greater concern.

Chloramine byproducts

Among those are iodinated disinfection byproducts, which Richardson called “the most toxic (disinfection byproducts) known.” This group of byproducts is not regulated.

Her research found that the rate of iodinated byproducts such as iodoacetic acid, the most genotoxic disinfection byproduct of the more than 100 that have been studied, were higher in chloraminated water treatment systems.

Genotoxic substances can damage the genetic code of cells, potentially causing a whole host of health issues, including cancer. Based on studies with test animals, iodoacetic acid could be cancer-causing, although researchers haven’t confirmed that in humans yet.

Though the iodinated family of disinfection byproducts is more commonly found in coastal water treatment plants, other factors, such as being downstream from a coal-fired power plant, can also provide the natural iodide needed for the reaction with chloramine that forms iodoacetic acid.

Regulation stagnation

Why aren’t disinfection byproducts that toxicologists have flagged for carcinogenic risk subject to more regulation?

Federal regulations on drinking water take a long time to establish. That’s been a point of frustration for Bob Bowcock, a 40-year veteran of the water utility industry.

“If we decided we were going to regulate a chemical toxin in drinking water today, and I had a child today, I would be going to my child’s college graduation before we would have a regulation for that drinking water contaminant,” Bowcock said.

As a water treatment expert, consultant and managing director of Integrated Resource Management in Claremont, California, Bowcock works closely with environmental activist Erin Brockovich on water treatment issues. One of them is chloramination and a corresponding lack of disinfection byproduct regulation.

Bowcock visited Columbia in 2016 at the request of the Safe Water Coalition to advise the city about improving the safety of its drinking water. One method would be a move away from chloramination.

“It’s frustrating because you talk to the water operators, they want to do this; you talk to the engineers, they want to do this,” Bowcock said. “You talk to the city management, and publicly they’ll say, you know, they want to do this, and we’re still dragging our feet.”

Water and Light’s position

Still, the staff of the Columbia Water and Light Department sees the equipment upgrades as essential. On a tour of the McBaine Water Treatment Plant, Kevin Wiggins pointed out each and every part slated for improvement in the upcoming project. He was like a kid on Christmas morning.

“I can’t wait,” said Wiggins, the plant manager.

Beyond restoring daily capacity to make sure Columbia is prepared for higher water demand, he said the changes will increase efficiency.

New aerators will come with easier maintenance access. Chlorine holding tanks will be given new space near its final destination, meaning less time in the pipes.

The result, he anticipates, will be an easier job for plant operators.

Other parts of the plant will become more automated, a feature Carrico is looking forward to. Automation means more reliability and safety, and he said it will “by no means” lead to any change in staffing.

Wiggins also pointed out that while the improvement project won’t be doing away with chloramination, it does set the stage for future improvements along that path.

“I’m a free chlorine guy,” Wiggins said. “I love free chlorine. I would love to see us go back to free chlorine.”

Chloramine alternatives

What would it look like if Columbia abandoned choramination?

About one in five Americans drinks water treated with chloramination, according to the EPA. As Bowcock put it, “Any joker with a 55-gallon drum and a pump can do chloramine.”

To move away from chloramines, the plant would need to reduce more of the organic carbon in the water initially, since it reacts so strongly with free chlorine to create suspicious byproducts.

There are technologies designed to do just that. Visitors to the Brita website are greeted with proud declarations of the product’s ability to filter out just about anything that humans wouldn’t want to be chugging down.

Activated carbon, one of the technologies used in Brita filters, uses a layer of organic material such as coconut shells to catch unwanted contaminants by forcing them to bond with the carbon material.

Britas aren’t cheap, though. Not everyone can afford to filter their own water at home, leaving the responsibility of clean tap water to the treatment plant. But what if activated carbon technology could be used on the front end, at the plant?

Experts have praised granular activated carbon as an alternative to chloramination. The technology catches more of the organic carbon in the source water, meaning treatment requires less disinfection. It could establish a path away from chloramination.

HDR, a consulting firm working with the city on water issues, studied how granular activated carbon technology might be applied to the McBaine plant’s current treatment process. Its findings were promising and were presented to recommend the technology in a Water and Light meeting in October.

“It’s always been identified as a very viable technology,” Carrico said.

Bowcock said that to not pair leading systems like granular activated carbon with the city’s newly improved plant would be a waste.

“I mean, why would you do that? Why would you spend millions of dollars upgrading your treatment plant and then turn around and put crap in it?” he said. “It would be the equivalent of buying a Maserati and putting the doughnuts out of a Toyota on it for tires.”

But Wiggins pointed out that granular activated carbon wouldn’t be the end-all, be-all for a return to chlorine. Such technology would cost tens of millions of dollars to implement at the plant, based on HDR estimates. With no regulatory driver that calls for it now, funding for that caliber of improvement is up in the air.

A rate increase — perhaps of $2 or $3 a month — is a possible solution, but passage would be subject to customers and the City Council. Gauging public willingness to pay more for utilities has been a challenge for Water and Light.

It’s an issue that Water and Light is hoping to explore further, but for now the department is concentrating on the project at hand.

Looking ahead

The city will start accepting bids for the project early this year. With the bidding landscape shaken up by the pandemic, officials aren’t sure what to expect in terms of cost.

City officials have thrown around the idea of rate increases, but it all comes down to what customers are willing to pay for their water.

Activists like Ryan and Brown have made their stance crystal-clear: Safe water is worth the cost.

“It shouldn’t be just the status quo, and it shouldn’t be just to avoid violation,” Ryan said during her address to the City Council. “It should be the best that we can offer.”

Either way, better efficiency and restored daily capacity are on their way to the plant. These aren’t the first improvements to the 50-year-old plant, and they won’t be the last.

At the entrance, photos on the wall show the plant partially submerged during the Great Flood of 1993. Besides the flooding and sandbags, the plant’s structures were also arranged differently back then.

“It’s going to change again,” Wiggins said. “I’m looking forward to it.”

Source link

judi slot online jackpot terbesar

Slot Terpercaya