Town of Berryville Waterworks Consent Order October 2024
October 22, 2024: The Town of Berryville, Virginia has received a Consent Order from the Virginia State Board of Health for the town’s Waterworks regarding Haloacetic Acid (HAA5), a chlorine disinfection byproduct (DBP). During the disinfection process, chlorine also reacts with naturally occurring organic matter that may be present in drinking water. DBPs can form during this chemical reaction. HAA5 includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid. The exceedance has been noted during routine quarterly water testing since the second quarter of 2023.
According to the Virginia Department of Health (VDH), people who drink water containing haloacetic acids (HAA5s) in excess of the maximum contaminant level (MCL) over many years may have an increased risk of getting cancer. In developing the standards, the EPA assumes that the average adult drinks 2 liters of water each day throughout a 70-year life span. If the water consumed over this 70-year span consistently contains DBPs, the cumulative effect is a potential increase in cancer incidence. There are no known acute effects of shorter-term exposure to DBPs.
The consent order notes the efforts of Town operators to reduce HAA5 levels, including:
Expanded testing for HAA5 and other water quality indicators have been instituted. The frequency and scope of testing has varied as each function or system of the water treatment and distribution system has been/is being evaluated, but HAA5 sampling has continued at regular intervals, averaging twice monthly.
Distribution line flushing continues as directed by consulting engineers. Half of the identified flushing sites are flushed each month on a rotating basis, so all sites are flushed in a 60-day period. Autoflushers were installed strategically and operate during frost-free months.
All three water storage tanks that serve the Town were cleaned and inspected during the first quarter of 2024. No repairs or recoating were recommended by the vendor to tanks or mixers. Cycling of water between towers has been increased by the optimization of pressure relief valves and booster pumps to avoid stagnation.
Storage levels were adjusted incrementally with testing to evaluate impact on disinfection byproducts. None of these products or practices were determined to be contributing factors to the exceedance. Chlorine feed rate continues to reflect the lowest level that maintains system residual levels.
In January 2024, the water treatment plant clearwell was cleaned and inspected. No fault was found in the structure or coating of this tank where primary chlorination occurs.
The surface wash system was repaired and the coagulant mixing and settling portion of the water treatment plant filter trains was cleaned in March 2024.
A chemist was retained to examine practices within the water treatment plant. All treatment protocols were reviewed, including chlorine feed and residual rates, potassium permanganate, alum, and carbon. Jar testing suggested a change in coagulant from alum to DelPAC could reduce organics and coagulate more effectively at a wider variety of pH in the raw water. The change was made under the supervision of Virginia Department of Health and DelPAC was the coagulant from February to August of 2024. However, no significant improvement was noted, and the coagulant was changed back to alum.
In August 2024, the settling tubes in one sedimentation basin at the treatment plant were lifted and deep cleaned. In September, the other settling tubes in the second sedimentation basin were lifted and deep cleaned. This isolation of each feature(s) of the treatment process for evaluation is the current focus of efforts to combat organics, though all best practices in treatment and distribution (as identified to-date) continue.
The Consent Order received by the Town is accompanied by a $2,734.00 fine and requires the Town to present a Corrective Action Plan to VDH before November 17, 2024. This plan must include:
- A timeline for submission of a preliminary engineering report (PER), developed by a Professional Engineer with expertise in disinfection byproduct control, which evaluates operations and proposes improvements, including:
- Optimized dosing of all treatment chemicals
- Best practices for frequency and duration of filter backwash and filter-to-waste (essential parts of routine filter cleaning and the discard of water following said cleaning)
- Reduction of water age in storage and distribution
- Identification of any additional options
- Assessment of the age and condition of the tube settlers and filter media
- A timeline for submission of revisions to the PER for the planned Plant Upgrade currently underway by the Town.
The Town of Berryville recognizes that it is unacceptable to provide anything less than fully-compliant water to the community we serve. The Town remains committed, corporately and individually, to determining the cause of the exceedance, returning to compliance, and continuing to evaluate and improve. Please direct questions to Deputy Town Manager Jean Petti at 540-955-1099 or deputytownmanager@berryvilleva.gov.