Wilderness Water Treatment Plant Water Advisory Incident

This webpage is dedicated to information regarding the Rapidan Service Authority's (RSA), the owner of the Wilderness water treatment plant (WTP) waterworks, water advisory incident. On August 21, following reports of an unknown odor in the drinking water RSA and the Virginia Department of Health Office of Drinking Water (VDH ODW) initiated a multi-agency response.

Final Update

On September 25, the VDH ODW has released a Investigative Summary Report concluding the investigation into the RSA objectionable odor event that began August 21.

VDH sent RSA a Notice of Alleged Violation (NOAV) on Wednesday, September 25.

Resources

Q & A

Findings and Conclusions

What were the findings of the investigation?

The findings of the investigation can be found in the Investigative Summary Report.

What caused the odor?

On September 13, VDH determined that a catastrophic failure of a raw water pump at the intake from the Rapidan River caused the objectionable odor. The catastrophic pump failure occurred on August 20, the day before customers noticed the objectionable odor. About two to three gallons of food-grade mineral oil was released. The mineral oil was likely thermally altered, burned, or scorched from the catastrophic pump failure. A taste and odor expert in Texas recreated the “WD-40” odor by heating the mineral oil. The taste and odor expert followed a new Standard Method 2150D Attribute Rating Test to determine that the food-grade mineral oil in the pump matched the odor in the water samples experienced by customers.

Did the food grade mineral odor pose a public health threat?

No, the food grade mineral oil did not pose a threat to public health based on toxicology reviews, epidemiological monitoring, and sampling results. Three chemicals not associated with disinfection by-products were found – isovanillin, Bis(2-chloroethyl) ether (BCEE) and benzaldehyde. The routine practice of the drinking water program is to confirm whether a contaminant is present by collecting confirmation samples and finding repeat detections. Two chemicals found in the drinking water, BCEE and benzaldehyde, were not confirmed through additional sampling. Only a single sampling event detected BCEE and this chemical would not have been associated with the odor. Benzaldehyde is used in the food industry and would not have been associated with the objectional odor. Isovanillin, an isomer of vanillin (which is used in the food industry), was a likely cause of the objectionable odor and found in multiple sampling events. Other unidentified hydrocarbons associated with the food grade mineral oil, which was either scorched, burned, or heated during the catastrophic pump failure on August 20, may have also contributed to the objectionable odor.

BCEE was found in one sampling event in finished water collected on August 21 during the Do Not Use Advisory. BCEE is a colorless, nonflammable liquid that is used as a solvent for some lacquers and oils, and as a chemical synthesis intermediate. The concentration found in water was very low, 13.7 µg/L, just above the detection limit of 10 µg/L. Someone who drank water containing this chemical at this concentration over a period of years could have an increased risk of cancer.

From the investigation’s start on August 21, 2024, state agencies had 98 total samples analyzed for over 2,357 individual analyte results. Analyses included 21 published analytical methods by certified laboratories and six research or pending publication methods. The state agencies informally coordinated or contracted with laboratories specializing in unknown contaminant identifications and taste and odor analysis. Two methods that were utilized are revisions to published methods or are pending publication. The agencies evaluated some samples with very sensitive tests, including high resolution scans, mass spectrometry, and chromatography tests.

Were any other contaminants found in the water and are they harmful?

Sampling found compounds associated with disinfection byproducts (DBPs). Scientists have identified hundreds of DBPs. Several types of DBPs have limits set by the U.S. Environmental Protection Agency (EPA): trihalomethanes (THMs), haloacetic acids (HAAs), chlorite, and bromate. EPA set these limits by balancing the health benefits of water disinfection with the risk of exposure to disinfection byproducts. To learn more, visit EPA’s National Primary Drinking Water Regulations – Disinfection Byproducts. If DBPs are above the limits set by EPA, the water system must take action to reduce the DBPs. Actions could include adjustments to organics removal processes, disinfection dose and location, and distribution system management. The water system must also notify all of their customers of the DBP levels.

Why did it take so long to find the answer to what caused the odor?

The first pump failed on August 20 and RSA did not share information with state agencies until September 3. See VDH’s investigative summary for a detailed understanding of the actions and work that took place over time.

How can this problem be prevented from happening again?

VDH has offered several recommendations in the Investigative Summary Report to RSA to prevent this from happening again. One recommendation is for RSA to routinely and regularly monitor its raw water. A second recommendation is for RSA to add additional treatment processes, such as granular or powered activated carbon.

What was the cost to perform the investigation and the source of the funding?

An exact cost cannot be determined. Several thousands of dollars in lab sampling occurred. Many persons from local, state, federal, and academia helped in the response, redirecting efforts from other tasks to focus on the objectionable odor event.

How frequently do public water systems take water quality readings and samples?

Water quality sampling is based on the type of treatment and the population served.

Will RSA be cited for any violations?

VDH sent RSA a Notice of Alleged Violation, which can be reviewed here.

What Happened

What happened? 

On August 21, out of an abundance of caution and in conjunction with the Virginia Department of Health (VDH), Rapidan Service Authority (RSA), the owner of the Wilderness water treatment plant (WTP), issued a Do Not Use water advisory after receiving complaints of an odor associated with the drinking water. RSA investigated the odor concern and determined that a Do Not Use advisory was necessary given the specific odor observed.

On August 24, RSA, in conjunction with VDH’s ODW, changed the Do Not Use Water Advisory to a Do Not Drink Water Advisory.

On August 27, RSA, in consultation and agreement with VDH, lifted the Do Not Drink Advisory to allow consumption and all other uses with drinking water.

Who responded to the event?

On August 21, following reports of an odor in the drinking water that is typically associated with hydrocarbons contamination, RSA and the VDH Office of Drinking Water (ODW) initiated a multi-agency response that included: Rapidan Service Authority, VDH, the Virginia Department of Environmental Quality (DEQ), the Virginia Department of Emergency Management (VDEM), Virginia’s Department of General Services Division of Consolidated Laboratory Services (DCLS), USEPA, and Orange County.

Why was the advisory lifted?

The RSA lifted the advisory on August 27, in consultation with the VDH ODW, for three primary reasons. First, laboratory sampling data over multiple days demonstrated that the drinking water fully complied with federal and state drinking water standards. Next, VDH’s daily inspections of the water treatment plant and distribution system confirmed that the objectionable odor in the drinking water was no longer present at the water treatment plant and had sufficiently dissipated in the distribution system to no longer be a concern. Finally, VDH substantially completed its epidemiological investigation and found no evidence of any negative impact from exposure to the drinking water. Review by ODW’s subject matter experts, toxicologists, and U.S. EPA Region 3 did not find any reason to continue the advisory.

Miscellaneous Questions

If I want to buy a filtration system, what should I buy?

There are many options and price ranges, depending on the concern to address, the treatment technology or device desired, and the operation and maintenance desired. Many treatment devices and filters can adequately address taste, odor, and aesthetic quality concerns. US EPA has a fact sheet, which might help. US EPA also has information on reverse osmosis systems, point of use and pitcher filters for lead removal, and filter/treatment technologies for other contaminant removal. There are several accredited third-party certifications for water filters, including NSF, WQA, IAPMO, UL, and CSA. At this link, NSF provides a good three-step process for owners who are considering purchasing a home filter or water treatment system.

Will RSA be increasing the price of drinking water to account for the new recommendations?

Va. Code Section 15.2-5100 describes the process, communication, and public notice required for water and wastewater authorities. Va. Code Section 15.2-1536 states in part that the rates for water (including fire protection) and sewer service (including disposal) shall be fair, reasonable, just, equitable, and sufficient to cover the expenses necessary to operate and maintain the service. VDH does not regulate billing practices.

What does enforcement specifically look like?

RSA has 15-days to request an informal fact-finding proceeding (IFFP) and a case decision. VDH suggested that RSA consider entering into a consent agreement to memorialize milestones and timelines for action. Notwithstanding the preceding points, ODW expects RSA to submit a detailed plan within 60 days and to meet monthly with the Culpeper Field Office until all of RSA’s action items in its forthcoming plan are completed. RSA’s detailed plan would include a communication plan to build community trust, which could include a townhall event. The specific steps to ensure this type of event does not repeat are outlined by the recommendations in the investigative summary and the requested actions described on Pages 3-4 of the NOAV.

Sample Results

Source Water Assessment Report

Details of the Investigation

Investigation Summary of Concerning Odor at Wilderness WTP

Wednesday, August 21

Around 2:30 p.m., officials from RSA contacted VDH ODW to alert them of a system shutdown due to multiple customer complaints of odor in the water. RSA confirmed the presence of an odor that has been described as having a petroleum or “WD-40” smell. RSA stopped distribution of the water and notified VDH of the issue.

A multi-agency meeting was held at 5 p.m. to discuss how to start identification of the source of the smell as well as issuing a Do Not Use Water Advisory from RSA.

ODW contacted water facilities downstream of Wilderness WTP on the Rapidan and Rappahannock Rivers to inform them of the situation for observation and switching to alternate water sources.

Noticeable odor was detected at the wet well and the area located beside the wet well.

DEQ contacted Apex Companies, LLC, which is one of contractors on the State Lead Program, to support the odor investigation. Under the State Lead Program, DEQ retains one or more contractors through contract procurement procedures to perform emergency response activities as well as release investigation and corrective action at petroleum release sites. DEQ staff oversee work performed by State Lead contractors.

At 8 p.m., personnel from ODW, DEQ, the Virginia Department of Emergency Management (VDEM), and Apex were onsite to evaluate the smell and collect an initial round of samples.

VDEM collected samples at two locations (the facility wet well and pre-sedimentation basin) to perform a qualitative screening analysis to help with potential target analytes. The screening analysis returned a result of a possible hydrocarbon detection (benzene, phenol, and toluene).

At the same time, Apex collected water samples from the wet well, water treatment plant influent, and the finished water and submitted them to a VELAP-certified laboratory for volatile organic compounds (VOCs) (EPA Method 8260) and semi-volatile organic compounds (SVOCs) (Method 8270) analyses. The results were non-detect for all constituents, except for one constituent [bis (2-chloroethyl) ether at 13.7 ug/L] and for typical chlorination by-products which were detected in the finished water sample entering the distribution system.

At 8:24 p.m., the State Corporation Commission (SCC) deputy director of Pipeline Safety & Damage Prevention reported the following findings from an investigation of the Colonial Pipeline which crosses the Rapidan River five to seven miles upstream of the Wilderness intake.

As of 8:06 p.m., Colonial Pipeline Company has not found any leak indications.
Colonial Pipeline Company also found no indications of any contaminants consistent with refined petroleum product inside the water plant’s holding tank (per their environmental techs).
Both pipelines are up and running at regular operating pressure.
No leak indications observed at operating pressure.
Colonial Pipeline has demobilized from the site.

Thursday, August 22

A 9:30 a.m. meeting between responding agencies, RSA, and Orange County officials was held and a sampling/data collection team was formed to set sampling priorities and locations.

An 11 a.m. sampling/data collection team meeting was held, and sample collection and observation priorities were established – samples to be collected from the raw water, the entry point to the distribution system, and in the distribution system for volatile organic compounds (VOC) and semi-volatile organic compounds (SVOC) analysis. A protocol of utilizing non-potable water analysis methods for all water collections below the finished water tap at the plant site was set. Samples from the distribution system entry point and in the distribution system would be run using certified drinking water analysis methods.

RSA collected samples in the distribution system for VOC and SVOC analyses using drinking water methods and sent to a certified laboratory. These sample results were received on August 23 at 5:26 p.m. and showed VOCs consistent with disinfection byproducts, which are expected in finished drinking water using chlorine disinfection. No contaminants which would cause the odor issue were identified.

A map of the RSA service area was produced for tracking odor complaints and system flushing activities.

DEQ's water quality monitoring staff visited three established monitoring stations located at bridges over the Rapidan River, including the Route 522 and Route 3 bridges, which are upstream of the RSA water intake, and Route 610 bridge, which is downstream of the water intake. DEQ personnel collected field parameter data and made visual and olfactory observations. All observations and measurements were consistent with historical data, and no evidence of an oil or hazardous substance release was observed.

DEQ spoke with the watershed manager for the City of Fredericksburg’s police department. Police department officers floated and walked segments of the watershed from the City of Fredericksburg to above the RSA water intake. The officers did not observe any evidence of an oil or hazardous substance release.

A 3 p.m. meeting was held where an Incident Management Team (IMT) was formed, and the sampling data/collection team was folded into the Unified Operation Section.

Stafford County Utilities collected water samples around the area of their intakes (river and reservoir) on the Rappahannock, within the Lake Mooney Reservoir, an outfall from the transfer station as well as the intake station.

The Rappahannock-Rapidan Health District (RRHD) epidemiologist reviewed the database with no abnormalities detected. Epidemiologist reached out to local hospitals for awareness and reporting of any potential symptomatic patients.

DEQ began a source investigation, which included the following activities: investigating pollution reports in Orange County; reviewing historical Sanitary Sewer Overflow (SSO) reports; and inspecting nearby sites and activities, such as the golf course, the paving activities, and the on-site construction activities at the water treatment plant intake. DEQ collected Safety Data Sheets (SDSs) for products used in these nearby activities and compared chemical compounds to analyte lists. All lines of inquiries were explored, and no potential sources were identified.

Friday, August 23

At 8:30 a.m., the Operations Branch of the unified command (UC) met to discuss findings and set sampling objectives and observation activities for the day.

ODW personnel visited the Wilderness WTP early in the morning for updates and assessment of the situation.

Out of an abundance of caution and with the potential contaminant still unidentified a swimming advisory was issued by RRHD for a portion of the Rapidan River.

RSA observed that the odor was dissipating in the pre-sedimentation basin, but strong odor was still observed in the finished water. The flushing program continued, and filter backwash timelines were shortened.

RSA personnel collected an additional three samples, one at the distribution entry point and two in the distribution system. Samples were sent to the Department of General Services Division of Consolidated Laboratory Services (DCLS) for analysis during weekend hours when the contract laboratory was closed. These samples were expedited for testing and results were reported by 10:30 p.m. The reported results continued to show only VOCs consistent with disinfection byproducts from chlorination treatment.

Apex collected three additional samples for VOCs, SVOCs, and Diesel Range Organics (DRO) and sent them to the same laboratory. The samples were collected at the following locations: one sample in the Rapidan River upgradient of the water intake, one downgradient from the water intake at the intake for the Hunting Run Reservoir, and one in Wet Well #1 near the RSA intake. During sampling activities, Apex personnel made visual and olfactory observations of the river and noted no evidence of an oil or hazardous substance release. All results were received by 5 pm on August 27 and the results were not detected (ND) for all constituents at all three locations.

DEQ interviewed the general contractor overseeing work being performed near the water intake. During the interview, the general contractor stated that recent on-site work was limited to the upgrade of the electrical service. Specifically, new electrical wiring was being run from a new building at the top of the hill, next to the wastewater treatment plant, to electrical boxes at the wet wells. The new electrical service was being run within PVC piping that was buried in a trench. DEQ requested SDSs for all products being used in the project, and the general contractor provided SDSs for the piping glue, fuel and hydraulic oil additives used in the heavy equipment. At no time did the general contractor indicate any unusual circumstances or events had occurred at the wet wells; the general contractor especially did not mention the pump failure on August 20.
DEQ received SDSs for the pesticides used at the commercial golf course situated upstream of the WTP intake.
Stafford County reported that sample results from initial VOC sampling came back with no detections.

VDH epidemiologist interviewed five different families regarding concerns of illness and was working with four of the families to test urine for contaminants of concern.

VDH environmental health visited all permitted facilities, including restaurants, and left notifications asking them to cease operations and answered any questions.

DCLS provided test kits to RSA officials to be collected by VDH Epidemiology personnel, as needed, while samples were delivered by RSA to the laboratory in Richmond, VA.

A 5 p.m. Operations Branch meeting was held to discuss findings and establish activities for the weekend. Email coordination of the Operations Branch was decided upon while Operations leads would be communicating in the Unified Command meetings.

When initial SVOC results were received at 5:30 p.m., a VDH toxicologist was assigned to complete a toxicological review for the disinfection by-product VOCs and the Bis (2-chloroethyl) ether to determine the potential for these products to cause the odor and the potential health effects of consuming the product at that concentration.

Saturday, August 24

ODW staff reviewed SDSs for construction materials, pesticides, and herbicides used on the Wilderness WTP site and upstream businesses and recreational areas. ODW did not identify compounds used in sufficient quantities of concern but consulted with DCLS on a test plan to rule out these sources. DCLS planned to ship test kits on Monday, August 26, for this analysis.

VDH toxicologist supplied a report on the chemicals found that indicated no concerns for acute health risks.

At 11 a.m., ODW and RSA staff, along with Orange County officials, reviewed operational reports and test reports, and received a verbal report of plant site conditions and operations. RSA reported a lessening of the odor in the treatment plant and only a slight odor in the water leaving the plant.

ODW consulted with DCLS on utilizing a laboratory department that has equipment and expertise to identify unknowns in a variety of matrices. A test plan was discussed, and sample collection was scheduled during an ODW inspection on Sunday, August 25.

RSA reported an increase in community water usage based on wastewater volume and difficulty in filling tanks sufficiently overnight.

In the absence of a contaminant of concern and with no volatile compounds detected in any of the treatment process or distribution system and a continued dissipation of the odor in the treatment process, ODW supported RSA’s request to replace the Do Not Use Water Advisory with a Do Not Drink Water Advisory.
RSA reported issues with raw water wet well pumps that would make an immediate change to the Do Not Use Advisory difficult as repairs were necessary to keep up with demand.

At 10 p.m., with a temporary raw water wet well pump solution implemented, RSA, with support from VDH, changed from a Do Not Use Water Advisory to a Do Not Drink Water Advisory, and an inspection was scheduled by VDH staff for 10 a.m. the next day.

Sunday, August 25

Multiple ODW personnel performed an inspection of the plant facility and distribution system to assess odor. ODW reviewed operations records and collected samples for High Resolution Mass Spectral Analysis using gas and liquid chromatography from the DCLS laboratory.

ODW staff noted continued but lessened detection of the odor in the water treatment facility as well as the distribution system.

ODW staff performed taste assessments by swishing the water in their mouths and spitting it out. ODW personnel detected a taste in the water at all locations of the distribution system where the test was performed.

ODW provided some operational recommendations to RSA to try and rectify the lingering odor. Water demand would dictate the ability to fully execute those recommendations.

ODW held a meeting at 2:45 p.m. with RSA staff to review the inspection. ODW indicated it would not recommend a change in the advisory status at that time and scheduled an additional inspection for the next day.

ODW personnel delivered water samples that night to DCLS in Richmond to begin analysis first thing the next morning.

RRHD lifted the swimming advisory for portions of the Rapidan River.

Monday, August 26

DEQ reached out to subject matter experts in the water and wastewater treatment field and requested assistance with investigating the potential sources of odor in source water and/or in the treatment plant process, including researchers at Virginia universities and their partners. DEQ received and shared the recommendations with RSA, VDH, and DCLS for follow up, including recommendations on potential sources of the odor such as bacterial and other odor-causing chemical compounds.

An Operations Branch meeting was held at 1 p.m. with a Unified Command meeting held at 2:30 p.m. Updates from operations members included:

RSA – no detection of odors on the plant site; ODW to visit today.
RSA – collecting information on customer complaints to investigate.
Spotsylvania County - collected VOCs (8260) and SVOCs (8270) at their Rappahannock River intake and delivered samples to the lab. Expect results Wednesday, August 28.
RRHD - recreational water advisory lifted; posted signs removed yesterday.
RRHD - preparing to visit permitted facilities when advisory is lifted.
VDH epidemiologist – working with a handful of parents to get children tested; most likely existing conditions and not water-related due to symptoms or onset.
VDH epidemiologist – some reports of rashes to be investigated.

Multiple ODW personnel performed another inspection of the facility and distribution system. Odor in the water leaving the facility had reduced and was barely noticeable. Water in the distribution system continued to have a detectable taste and odor although reduced from Sunday.

A meeting was held with ODW, RSA, and Orange County staff to discuss findings and recommendations. VDH did not recommend lifting the Do Not Drink Water Advisory and RSA was in a position from a water production standpoint to implement some recommendations to help remove odor and implemented those procedures.

An inspection was scheduled for the next day at 8 a.m. to assess the plant and distribution system again.

VOC results for the Rapidan and Wilderness intake collected on August 23 came back with no detections. SVOC and DRO results were expected the next day.
In response to DEQ’s outreach, Virginia Tech connected DEQ, and subsequently VDH, to a water utility director in Wichita Falls, Texas, who is a nationally recognized researcher in taste and odor compounds. The researcher offered to provide support in the way of analysis of samples from the source water area and the WTP.

Tuesday, August 27

Verbal results from DCLS on the high-resolution mass spectroscopy analysis returned no contaminants of concern identified.

Multiple ODW personnel performed an inspection of the water treatment facility and distribution system. No detectable odors were identified at the facility and taste and odor concerns were only noted at two distribution locations in areas that had not been used or flushed since the Do Not Use Water Advisory was enacted.

RSA staff performed field analysis for cyanobacteria toxins, which were negative.

During a meeting between ODW, RSA, and Orange County staff following the inspection it was determined that ODW staff would support the lifting of the Do Not Drink Water Advisory while continuing activities to locate the source and identity of the odor. RSA lifted the Do Not Drink Water Advisory at 11:15 a.m.

ODW personnel collected additional samples at non-residential locations that might not have had much water use since near the beginning of the event. The purpose of this effort was to capture samples of water where the odor is still prevalent, to aid in future identification of the contaminant.

ODW personnel collected samples to be shipped to a researcher in Texas for a more targeted screening of taste and odor compounds that can be detected at much lower detection levels.

Wednesday, August 28

ODW personnel shipped samples for analysis of carbamates, herbicides, VOCs and SVOCs collected from the raw water wet wells and the distribution system entry point to DCLS for analysis.

ODW overnighted samples to the researcher in Texas who is a taste and odor specialist for analysis. ODW researched previous and current events of waterworks odor investigations and began outreach to those localities for additional information.

Spotsylvania County received analysis reports from their intake sampling conducted on August 26. All sample results were below the detection limit. Based on those results, Spotsylvania County resumed drawing water from their Rappahannock River intake.

Analysis reports for the DCLS High Resolution Mass Spectroscopy lab were received and posted on the incident webpage.

VDH, DEQ, and VDEM personnel held a coordination meeting at 3 p.m. to set a direction for continued investigation of the source of the odor. An investigatory approach was established and VDH ODW was established as the lead on the continued investigation.

ODW held a coordination call with RSA staff for continued engagement with operational conditions.

Thursday, August 29

ODW scheduled a meeting for September 3, between subject matter experts in the field of water treatment and environmental engineering to review actions and solicit ideas for continued investigatory processes.

ODW and DEQ reviewed the actions taken to date and potential areas for follow-up and investigation.

ODW requested additional test kits from DCLS for routine drinking water quality parameters not associated with odor.

ODW personnel visited the facility for continued follow-up and operational review. ODW personnel also coordinated with RSA management on continued investigatory responses.

DEQ submitted a request to DEQ’s EPCRA Program to generate a Tier II report that contains all facilities located in Orange, Madison, and Culpeper counties. The report was filtered for facilities within the Rapidan watershed above the WTP intake and was reviewed for BCEE and other odor causing chemical compounds.

Friday, August 30

Preliminary results from an odorant screening analysis received on August 29 identified two chemicals that could have contributed to the cause of the odor. These chemicals were identified as Isovanillin and TPIB (2,2,4-Trimethyl-1,3-pentanediol diisobutyrate). The concentration of each compound is unknown currently. Analysis of existing samples and additional sampling will occur to confirm findings and try to establish concentration levels. VDH is consulting with U.S. EPA, researchers, DEQ, and toxicology staff. ODW also completed another inspection of plant operations. Based on VDH's review and consultations, the drinking water can be used for all uses. Additional information on these chemicals, including toxicological information, can be found in the sample results/chemical fact sheets tab of the VDH incident web page. VDH and DEQ will continue to investigate the source and cause of the odor. VDH will provide additional information as it becomes available.

Tuesday, September 3

ODW convened a facilitated discussion between experts in the field of water treatment, water treatment professional organizations, waterworks leaders, the U.S. EPA, and state agencies involved in the investigation, to assess current information and crowdsource avenues for investigation that might not have been addressed to date. Some areas for investigation were suggested and ODW staff committed to follow up on those suggestions.

ODW and RSA staff held a meeting to discuss current operations and request information related to the raw water intake pumps and testing documentation.

ODW collected unused sample volume from initial VOC analysis from the contract laboratory that performed the testing and shipped those samples to the Texas laboratory performing low level taste and odor analysis.

The Texas laboratory sent information that indicated the preliminary identification of TPIB (2,2,4-Trimethyl-1,3-pentanediol diisobutyrate) was not confirmed and thought to be a potential false positive or laboratory contaminant.

ODW staff called manufacturers of chemicals used in water treatment to obtain lists of chemicals listed as trade secrets on Safety Data Sheets (SDS).

Wednesday, September 4

ODW and DEQ held multiple coordination meetings to discuss findings from activities and plan for future inquiries.

ODW received information related to chemical components of materials used in water treatment equipment from chemical manufacturers.

ODW coordinated with RSA on scheduling an assessment of the facility this week.

RSA provided information about food grade lubricants used in some of the WTP equipment.

DEQ completed a field investigation of a sheen on the ground surface and reported iron bacteria as to the cause, with no impact to the odor event.
On September 4, DEQ’s Water Quality Monitoring & Assessment Program (WQM&A) conducted a focused sampling event of the source water area in an attempt to determine whether any odor-causing chemical compounds could be identified in surface water samples. DEQ’s WQM&A staff also collected samples at the water intake, pre-sedimentation basin wet well, and the finished water. The samples were shipped to DCLS for VOC and SVOC analyses and samples were shipped the researcher in Texas.

Thursday, September 5

The taste and odor expert preliminarily identified a new chemical, benzaldehyde, that appears to be present in the drinking water from the samples submitted the prior week. All samples that contained the compound were in the post-treatment and distribution system and the odor could be detected in water prior to these sampling points. The expert is working with professors at Virginia Tech and Texas Tech to determine whether there might have been a chemical reaction during plant operations of a precursor chemical to form benzaldehyde.

ODW reached out to a distributor and service technician for the RSA raw water pumps to get additional information related to pump issues experienced at the plant. A follow-up meeting is scheduled for September 6.

ODW reached out to chemical manufacturer of a food grade lubricant installed in raw water pumps to see if they contained isovanillin and benzaldehyde. The manufacturer is researching all hydrocarbons and additives and will report back.

ODW consulted with a microbiological laboratory to determine potential testing that would identify a microbiological source of the odor. The laboratory determined it was unlikely that this event would come from a biological source given the facts of the investigation and recommended further organic chemical analysis. The laboratory also recommended a forensic materials scientist that could potentially link the scans already taken to a source material if it were identified depending on what the source was.

Friday, September 6

ODW issued an updated Source Water Assessment Report for the Wilderness WTP's Rapidan River intake. This report identifies potential sources of contamination in the watershed upstream of the drinking water intake, which will aid in the ongoing investigation.

ODW and DEQ met with the owner of the pump distributor and service technician for the RSA raw water pumps to get an understanding of the cause of the pump failures. The owner explained the pump failure was the result of replacing older pumps with higher horsepower pumps but not updating the electrical specifications to handle the additional load. The owner also provided a detailed description of the condition of the pumps when they were received. He noted that the pumps had experienced a significant thermal overheating event which resulted in significant damage to the pump windings and a scorching of the mineral oil contained in the pumps.
Subsequent to that meeting, RSA provided a timeline of the pump electrical issues.

ODW obtained additional information about the food-grade mineral oil used in the raw water pumps and is seeking information about wire coatings in the pump wire stators that had electrical issues. No identified compounds were components of the oil.

DCLS supplied analysis results for herbicide, pesticide, volatile and semi-volatile organic sample analysis. No chemicals of concern were identified, and results were added to the website.

An additional sample collection from intake wet wells, which had been isolated since the second pump failure on August 24, was scheduled for Monday, September 9.

DEQ coordinated sample analysis with the Texas lab for samples collected from the September 5 sampling event.

Monday, September 9

ODW, DEQ, and Apex inspected raw water pump wet wells #1 and #2 and collected samples from water that has been valved off and stagnant since two pump failures on August 24. The samples were sent to a VELAP-certified private laboratory, as well as the Texas taste and odor specialist. The equipment that was used for sampling was noted to have been coated by a substance likely to be mineral oil from the failed pumps.

Tuesday, September 10

ODW continued investigating the contents and materials in the raw water pumps including the mineral oil lubricant, wire stator varnishes, and other internal components that might have caused the detections of isovanillin, benzaldehyde, and BCEE. The motor varnish manufacturer thought it plausible that the chemicals identified could be a byproduct of heated mineral oil alkanes but thought it would be difficult to recreate that situation for analysis.
ODW provided an update of the investigation to the Orange County Board of Supervisors, including a timeline for reaching conclusions in the investigation into the cause and source of the odor.

Wednesday, September 11

ODW received preliminary results from the taste and odor specialist in Texas that samples submitted from collections of the wet wells # 1 and # 2 sampled on September 9 contained isovanillin but no traces of benzaldehyde. Using a mass spectra, the specialist was going to analyze samples specifically for those compounds to better quantify the results. The isovanillin was also detected in samples submitted from the DEQ survey conducted on September 4. Further analysis of the samples will be necessary due to these findings.

VDH and DEQ personnel joined members from the offices of the Secretary of Health and Human Resources and the Secretary of Natural and Historic Resources in an investigation status briefing with Senator Reeves and Delegate Scott’s offices. All resource needs are met. Staff continue to investigate questions and concerns raised throughout the event. As of last week, RSA reports that they are no longer receiving complaints about odor. All parties continue to closely monitor and engage in response and investigation activities pursuant to the Governor’s direction and leadership. All available effort continues to be applied to determine the source and cause of this incident and to leave no stone unturned to prevent this type of event from occurring in the future. Actions taken in the investigation thus far and a timeline of completion of investigatory events were shared.

Thursday, September 12

A sample of the mineral oil used in the raw water intake pumps was procured and shipped overnight to the taste and odor specialist in Texas to perform comparative analysis as well as some material science testing attempting to recreate some of the conditions the oil experienced during pump failures. ODW, DEQ, and the odor specialist reviewed sampling results and discussed what could be understood from the data.

ODW received sampling reports from the VELAP-certified private laboratory for samples collected on September 9 from wet wells #1 and #2 that experienced two catastrophic pump failures on August 24 and have been isolated since that time. These samples showed no detections for VOCs or SVOCs, but did show detections of Total Petroleum Hydrocarbons Diesel Range Organics (TPH DRO) at a concentration of 0.603 mg/L in wet well #1 and 1.06 mg/L in wet well #2. Total Petroleum Hydrocarbons Oil Range Organics (TPH ORO) were also detected in Wet Well #2 at a concentration of 1.5 mg/L. Total Petroleum Hydrocarbons is a term used for any mixture of hydrocarbons founds in oils. Since oils are made up of so many compounds, analytical tests scan hydrocarbons in a range based on the amount of carbon atoms present. TPH DRO analyzes hydrocarbons in the C10 – C28 range, meaning the result is the total amount of compounds containing a minimum of 10 carbon atoms to compounds containing a maximum of 28 carbon atoms. TPH ORO scans from the C20 – C35 range. Mineral oils such as the ones used in the failed raw water intake pumps that were in the wells that were sampled typically contain hydrocarbons in the C15 – C50 range. These results along with the field observation of a mineral oil-like substance on sampling equipment makes the failed pumps a possible cause of the oil detected in the wells. Investigation will continue to link the odor to contents of the failed pumps.

RSA scheduled a contractor to pump the remaining liquid out of the isolated raw water intake wells on September 13. ODW and DEQ were present to record observations from the emptied wells. RSA will clean the wells before reinstalling the repaired pumps.

Friday, September 13

The taste and odor expert in Texas confirmed that heated mineral oil, received directly from the pump repair business and like the mineral oil used in the catastrophic pump failures, produced a “WD-40” odor identical to the odor observed in the drinking water samples.
The taste and odor expert had a high level of confidence that the odor event was directly related to the mineral oil release on August 20.

Friday, September 20

RSA informed ODW in a meeting that it had determined that the temporary wiring serving the pumps was undersized, starving the pumps for current, and causing the pump failures. RSA also advised that the general contractor has worked with the project engineer on the design for an upgrade of the temporary wiring, and an electrical contractor will be used for the work. The work will be checked and inspected by an independent electrical contractor, very familiar with large construction projects.
ODW staff inspected the raw water intake wet wells and observed residual odor and what looked to be mineral oil residue coating some of the walls and equipment surfaces in the well. ODW requested the wells be cleaned out prior to being returned to service and provided a contractor recommendation received by DEQ for the work which will require confined space certification.
During the pump-out of the wet wells that occurred on September 13, ODW staff observed groundwater intrusion in the wet well that houses two pumps. While this issue is not related to the odor event, and could be addressed later, the opportunity exists to complete repairs now since the wet wells are already being bypassed. RSA indicated support for this work, but that it would be a significant project requiring excavation around the wet wells, and therefore would need to be planned for a later time. In the meantime, ODW recommended that RSA evaluate whether a temporary fix, using a product such as hydraulic cement internal to the wet wells, would be worthwhile.

U.S. EPA Region 3 Support

U.S. EPA Region 3 Support

EPA Region 3 has been providing additional support during the incident. EPA has shared the following information through the event:

Regarding Bis(2-chloroethyl) ether (BCEE):

Staff could not find any specific evidence or data suggesting that BCEE could form during water treatment through chlorination of an organic precursor. EPA staff found information about the industrial scale production of BCEE, and based on that information, EPA thought it was unlikely that BCEE would form during drinking water treatment.
In the studies evaluated, the majority of BCEE found in drinking water was confirmed to be from industrial dischargers. During the National Organics Reconnaissance Survey of the 1970s, there were some detections of BCEE. One of those detections, in Philadelphia, was traced back to an industrial discharge to the sewer. The BCEE passed through the wastewater treatment plant (WWTP) into the Delaware River. The investigators used NPDES permits for industrial dischargers in the area to find the responsible company.
EPA reported on one study that investigated leaching of organics from a pilot drinking water system with mixed plastic components. In this situation, EPA noted that several chloro-organic chemicals in water passed through the pilot plant, but again, no BCEE found.
Given the small sample size and methods used, EPA staff did not think there was sufficient data to state with high confidence that there was no BCEE in the source water. Thus, it may not be appropriate to completely rule out the possibility that BCEE was present in the source water, if the BCEE detect in the finished water was not a sampling or lab artifact.
Treatment of BCEE, using common and even advanced drinking water treatment, was not encouraging based on EPA’s literature review. While granular activated carbon (GAC), and presumably powered activated carbon (PAC) can remove some BCEE, those treatment processes could not be characterized as highly effective based on a literature review. However, strong oxidation processes, such as those involving the Fenton process, were found to be highly effective at destroying BCEE.
Regarding membrane treatment, EPA hypothesized that only reverse osmosis or a tight nanofiltration membrane would remove BCEE. EPA staff also would expect the BCEE to pass through microfiltration or ultrafiltration unless the latter processes were specifically modified and enhanced to remove dissolved organic compounds.

Regarding Isovanillin and TPIB:

None of the three contaminants identified thus far (TPIB, Isovanillin, BCEE) are common drinking water contaminants. Chemical concentrations and odors have declined since the problem started. Sampling should continue for these contaminants for some time to ensure the concentrations decay and do not come back. The largest likelihood was a point source contamination event that has passed, either upstream or within the plant. It would be worth taking samples in the locations the chemicals were found plus in the raw water to assess if the contamination came into the plant that way. If there is a second event, a much bigger issue exists, and knowing if the source is the raw water or within the plant is important to figure out.
Isovanillin is widely used as a flavor enhancer and sweetener in the production of sugar, popsicles, beverages, desserts, and tobacco and alcohol products. It is also used in pharmaceuticals. This information could provide clues as to whether the source is from an industrial discharge. Since it is safe to use in food products, this fact could lessen concern about the odor.

Regarding the investigation of the source of the odor, EPA stated that verifying no new equipment in operation at the water treatment plant, evaluating construction activities, and application of any applied sealants associated with construction would be useful.

Regarding membrane treatment, EPA could provide additional support and expertise, if needed.

EPA concurred that the DCLS high-resolution scan showing no contaminants of concern, VDH’s inspection and finding that no odor was at the water treatment plant, that flushing would support lifting of the Do Not Drink Advisory.

Alternate water for drinking should continue as long as the Do Not Use and Do Not Drink Advisories were in effect. Federal assistance is possible on providing bottled water and bulk water if Virginia would like that additional support.

Continue to provide flushing guidance for customers who are experiencing objectionable water. Customers must adequately flush the water supply at their homes to fully remove the objectionable water. Businesses that closed will likely need additional support on flushing guidelines. Flushing guidelines should be readily available, and the Rapidan Service Authority should provide support on flushing guidelines and questions. The Do Not Drink Advisory should remain in place until VDH determines that there is no risk to public health.

EPA will continue to help as requested. EPA will attend relevant meetings and updates to stay informed of decision-making throughout the event.

Background

Last Updated: September 27, 2024