Ban on Sale of Perchloroethylene in CA

[Guest]

Interesting, informative article on the ban of the dry cleaning chemical perchloroethylene (PCE).

CA Ban on Perchloroethylene

I think CA is once again leading the pack in terms of environmental reform. The sale of PCE in drycleaning operations should have been banned A LONG TIME AGO. EPA has picked up this issue at the national level and will probably put through similar rulemaking at the Federal level.

It humors me a tad to read the evils of PCE in the news article, when the real problems arise from the degradation breakdown products, such as:

Trichloroethylene (TCE) - much more persistent, toxic, and mobile. Lower solubility, so get more of it in dissolved phase. The OSHA criteria was vacated for TCE because it is known to have relatively high toxicity. The standard will most likely be dropped significantly.

Vinyl Chloride (VC) - more persistent, toxic, and mobile. VC has yet even a lower solubility so you get even more of it in dissolved phase. Toxicity criteria in water is 1 ppb (as opposed to 3 ppb for TCE and PCE in FL). Harder to get 'clean' to 1 ppb. Degradation usually of contaminant typically gets 'stalled' at the VC phase - last chlorine atom difficult to strip off to complete mineralization to Ethene, Ethane.

1,4-Dioxane (1,4-D) - this is the truly evil component. It was used as a stabilizer in PCE, TCE mixtures to some degree but more prevalent in 1,1,1-Trichloroethane (1,1,1-TCA) formulations. 1,4-D is completely miscible in water - its' solubility limit is infinite. It is completely unretarded in groundwater flow, so it 'goes' where the groundwater goes. Toxicity has been dropped from 10 ppb to 5 ppb to 3.2 ppb recently in FL. Analytical methods are difficult for this compound - reliable detection limits are around 50 ppb. This compound has specific gravity of 0.998 and practically no volatility so it loves to stay in the dissolved water phase. Treatment is difficult (expensive) for the same reasons.

Many of the projects I work on are contaminated with chlorinated solvents, so I thought I would share a few ideas/impressions.

JR

 

[udpolo15]

I don't agree that it should be banned. PCE, PCBs, asbestos all provide many benefits, sometimes that are unmatched by alternatives, when used properly. Many of the problems with PCE are from old LUSTs. Current regs are adequate to protect the environment, though enforcement is always any issue.

This view is related to soil and groundwater (and air to some extent), but I don't have any info on IDAQ issues with PCE, though there are ways to control those issues as well.

 

[FusionWhite]

PCE is one of the things I run into most often when doing site investigations. Ive been working on a site now for over 8 months because of PCE contamination. Should it be banned? It depends I guess. Ive heard that PCE can also be used in the manufacturing of Meth which probably moves it up on the government hit list.

And yes many dangerous materials have no better substitute. Asbestos is still one of the best insulators around and is one of the most fire resistant materials you'll ever find. Too bad it kills people.

 

[RIP - VTEnviro]

In the town where I grew up, there was a large strip mall when I was a little kid with all sorts of various shops. It was always hoppin'.

Then the dry cleaner there contaminated the groundwater/soil with their chemicals. Over the next couple years, everything went out of business there and the place was condemned. It sat there 15 years before they rebuilt it.

 

[udpolo15]

Too bad it kills people.

It kills people in when it is friable. If you maintain it properly, there isn't a problem with it. People wasted a lot of money in the 80s ripping out perfectly safe asbestos and probably cause more harm (because of work practices), than good.

 

[Guest]

I don't agree that it should be banned. PCE, PCBs, asbestos all provide many benefits, sometimes that are unmatched by alternatives, when used properly. Many of the problems with PCE are from old LUSTs. Current regs are adequate to protect the environment, though enforcement is always any issue.
This view is related to soil and groundwater (and air to some extent), but I don't have any info on IDAQ issues with PCE, though there are ways to control those issues as well.

I agree with some of the points of your argument - there is a certain logic to trying to "make the most" out of hazardous chemicals that you use because they are "the best". However, there are groups of chemicals that need to be phased out because the beneficial use does not outweigh the risks and damage they cause.

Let me take a different industry for a moment.

Copper-Chromated-Arsenic (CCA) treated timber. Up until 5-yrs ago this stuff was tha bomb. Everyone in Florida used it from decks to playground equipment to fencing to marine docks. The stuff was awesome because unfavorable environmental conditions (heat, moisture, bugs, salinity, etc.) had practically no detrimental effect to the strength or durability of the wood product.

However, leaching procedures demonstrated that the metals, especially the arsenic - a known toxin and carcinogen - was leaching at concentrations much greater than what was considered safe for human exposure. Moreover, leaching procedures conducted on C&D landfill wastes containing CCA-treated wood exhibited HAZARDOUS characteristics (e.g. toxicity).

The industry was forced to change up their business model, with the assistance (and proper incentives) from regulators. The industry has switched from CCA to a compound referred to ammoniacal copper quaternary compound (ACQ). This formulation retained the desired properties of copper in abating wood deterioration while eliminating the toxicity of the chromium and arsenic. In most cases ACQ provides adequate protection, except for the cases of extreme environmental conditions (e.g. marine setting). In most cases former CCA-wood treaters have been allowed to delay investigations and corrective actions ath their properties as long as contamination did not extend off the property and as long as the wood treater converted to ACQ and remained an active wood treating facility. This quid-pro-quo approach allowed the industry to remain viable and continue to provide a necessary product while remaining competitive. It gave regulators a chance to claim victory in the sense that less PCE was entering the environment.

Okay .... I can hear you ...

...

... and

.

My point would be that the use of PCE in the drycleaning industry poses the same sort of industry use - risk to human health and the environment causality that CCA-treated timber. There are safer chemicals that do almost as good a job as PCE. The one major drawback is that they require a capital investiment in new equipment. This is an instance where the regulators can step in and provide some quid-pro-quo incentatives so that the transition from PCE to an alternative is financially feasible and attractive.

That is the key to handling industries that have undesirable 'wastes'. In fact, the very future of the Resource Conservation and Recovery Act (RCRA) is pending on the ability for industries to enhance the recycle and reuse aspect of their business as well as bring-in safer, economical alternatives to chemicals (and processes for that matter) that generate waste and risk to human health and the environment.

*** Ramble Off ***

So, to bring it full circle - I think CA is doing the right thing by phasing out the use of PCE. I just wish the push to reduce and recycle within the drycleaning industry and others came sooner, rather than later.



JR

 

[Dleg]

JR - do you have any good links for ACQ treated lumber, regarding durability? I have a project for a 1-mile wetland boardwalk, and my A&E contractor came back to me saying that "after extensive research" (more than 2 years ago now), CCA was still the best material for the project, because none of the alternatives had yet been demonstrated to be effective in that particular environment (freshwater wetland).

I've got USFWS now pressuring us as to why we chose CCA lumber - my response so far is to quote our designer, and say that we have mitigated for leachability by calling out a dual coating system on top of the lumber. If ACQ has become more accepted, I'd be interested in switching (we're not even at the bidding stage yet).