During Water Week 2017, the Water Quality Assn. (WQA)...
WQP: What types of water systems are most affected by the new arsenic level standard?
Greg Gilles: The small and very small community (< 3,000 population) and non-transient, non-community systems such as schools and day care centers will be affected most. Any form of treatment will require these systems to spend money they are not spending now and/or do not have budgeted. The smaller systems are typically under-resourced compared to the larger municipal or public systems with more infrastructure and financing vehicles.
For centralized treatment (at the point-of-entry/wellhead typically), the fewer the number of connections served by the water system, the greater per month cost impact, as the capital and operating dollars are spread over fewer ratepayers.
WQP: Approximately what percentage of systems will be unable to meet the new standard by the given deadline? What is their biggest challenge?
Gilles: Simply put, the majority of systems will not have a solution in place by the January 2006 date. I would estimate that conservatively less than 10% of the 4,000-plus estimated systems affected by the rule have acted or will have a system or solution in place, or significantly underway before the standard takes effect.
The number one issue for many, if not most, of the smaller water systems is money. This is a challenge because most of the funding mechanisms that exist at the federal and state levels favor the larger systems that involve greater quantities of money (typically more than $250,000) in the form of grants.
WQP: Do you think POU/POE arsenic treatment could become a solution for municipalities struggling to meet the new standard?
Gilles: The POU option is certainly a technically viable option (and one supported by EPA) for very small systems to achieve compliance with the new arsenic rule. Some states, however, such as California, are not currently embracing this approach. From a cost and technical perspectives, POU (under counter-type options) such as adsorptive iron media-based cartridges and RO have some advantages and should be considered for very small systems (< 25 connections).
However, administratively, these options are less attractive and are not widely embraced by communities due to management aspects, sampling and monitoring, access issues and insufficient technical expertise locally to manage multiple “mini” treatment systems. The cost gap, which was always the primary driver that existed between adsorption-based centralized treatment and POU over the past couple of years, has closed considerably, making POU less attractive when considering the total picture.
As far as POE (whole house treatment) is concerned, this approach for a municipality is also viable but unattractive due to cost. Even for community water systems with less than 25 connections, POE treatment for individual homes will always be more expensive, considering both capital and operating costs, than a single centralized treatment system at the wellhead. It will also require more operation and maintenance because multiple small systems will need to be managed versus a single system.
WQP: What technologies are best positioned to help small systems comply with the new MCL?
Gilles: Public water systems need solutions that are simple; easy to operate and maintain; do not generate liquid or hazardous waste; do not require large amounts of space; and are cost-effective (both capital and operating costs). In EPA’s full-scale Arsenic Demonstration Program (Round 1 and 2) being implemented by various technology vendors at 40 sites throughout the nation, 25 of these sites are utilizing adsorption-based technology, the largest category being iron-based adsorbent technology. Iron-based adsorbent technologies are being implemented for the reasons stated above. Soon to join the ranks of best available technology (BAT), these technologies will supplement and in many cases supersede the former BAT to offer public water systems lower cost alternatives to meet compliance objectives.
WQP: What are some steps communities can take to meet the new standard?
Gilles: First, they need to determine if they will be in or out of compliance with the rule. System monitoring data for four quarters will be needed to demonstrate their position. Communities should work with their regulatory agencies to understand the requirements and begin executing a definitive plan. An engineer will often be involved in this process to assist because plans may have to be reviewed to gain regulatory approvals. An important part of the plan is to obtain a complete water analysis and submit this information along with site-specific information to their engineer and commercial technology providers who can prepare cost estimates or firm proposals to implement treatment solutions. Concurrently, systems should begin to secure financing and funding options, and gain “buy-in” and approvals from their community or board members on the proposed plan. There are some good resources available on most state and EPA websites that can also be referenced.
WQP: How will the new standard affect the water treatment industry in 2006?
Gilles: The arsenic rule is one, if not the most, far reaching rulemakings in the history of the Safe Drinking Water Act. The standard was lowered by five times from the previous standard, carrying with it very significant cost impacts for thousands of communities in roughly 35 states. With the majority of public water systems still yet to implement a solution, the positive impact for the water industry is still ahead. Not only will the demand for technology be obvious, but general drinking water business, construction and services in the water treatment industry should benefit. One of the remaining questions that is difficult to answer is: How quickly will systems affected by the rule phase into compliance? It may be several years.
WQP: Do you think the 10 ppb MCL is low enough? Will EPA con-tinue to lower it?
Gilles: There has been tremendous debate in the past several years over the science and policy of the 10 ppb standard. The long-term arsenic chronic toxicity and carcinogenicity to human beings at low concentrations is repeatedly being confirmed. There are some who could provide a persuasive argument for a standard lower than 10 ppb.
However, given the degree of due diligence and special committees convened to investigate the science, costs and benefits of the rule, as well as the political climate, it appears very unlikely that this number will be modified in the foreseeable future. wqp