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    2015 Biosolids Management Program Performance Report

    The Biosolids Management Program (BMP) approach proved to be a good fit for the goals set by the facility for good quality production of biosolids. Biosolids are the organic products resulting from the treatment of domestic sewage in a treatment facility and are rich in nutrients. According to USEPA, they can be safely recycled and applied as fertilizer to sustainably improve and maintain productive soils and stimulate plant growth. The BMP is a structured program comprised of elements that cover all aspects of biosolids management including - process efficiency, communication with interested stakeholders, and training along with other crucial factors. Consistent with the City’s Environmental Policy Statement, the Richmond Wastewater Treatment Plant is committed to the following principles of conduct set forth in the Code of Good Practice. The treatment plant focuses its available resources to produce Class B Biosolids. The treatment plant strives to maintain, improve, and protect the environment through its treatment/production of biosolids. The treatment plant makes every effort to ensure that the public is not endangered by the treatment/production of biosolids at the treatment plant during transportation, storage or application at permitted sites. The treatment plant shall obey all applicable federal, state, county, and local laws, rules, and regulations. We pledge to “do the right thing” and uphold the following principles of conduct. A- COMPLIANCE: To commit to compliance with all applicable federal, state, and local requirements regarding production at the wastewater treatment facility, the Richmond Wastewater Treatment Plant facility has elected to: 1) Meet concentration limits, 2) Meet class "B" pathogen standards; 3) Achieve 38% volatile solids reduction for vector control

    As treatment for its anaerobically digested biosolids, Primary biosolids is collected from our primary clarifiers, grits removed by hydro-grit units and thickened in four gravity thickeners. Waste activated sludge is pulled from the return biosolids stream and thickened in four thickening centrifuges. Biosolids is then pumped to one of the five anaerobic

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    digesters. Overflow from the digesters is stored in one of the 2 biosolids storage tanks and pumped to one of the five dewatering centrifuges where polymer is added. Once dewatered, biosolids is stored in the plant's storage pads and then hauled to land application site by the hauling/land application contractor.

    1- Concentration Limits. The chart below shows the biosolids metals concentration in 2015 and the concentration limits for Arsenic, Mercury, Molybdenum, Selenium, Cadmium, Lead, Nickel, Copper and Zinc. All metal analytical results were under the required concentration limits.












    Arsenic Mercury

    Molybdenum Selenium

    CadmiumB io

    so lid

    s m

    et al

    s co

    nc en

    tr at

    io n

    (m g/

    kg )

    2015 Biosolids Metals

    Regulatory Limit mg/kg Jan-15 Mar-15 May-15 Aug-15 Sep-15 Dec-15

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    2- Class "B" pathogen standards:

    The temperature optimum required for microorganisms to stabilize the organic matter is 95F. During the month of April the average digesters temperature was below 95 o due to high volume of biosolids. The wastewater plant used to receive landfill leachate until October 7th. Land fill leachate was identified to be the potential cause of

    The primary and secondary clarifiers had low settleability issue. High flow from clarification tanks had to be pumped to the digesters causing the temperature to drop below 95F. The second boiler was repaired and put in service while running tests and investigations to diagnose the problem. Beginning of May the temperature was back to normal to comply with the federal regulation [40 CFR 503.32(b) (3)].

    3- Vector Attraction Reduction: [40 CFR 503.33(b) (1)/alt (10)].

    Samples are pulled at least 1x/2 months; if the reduction is less than 38%, additional samples are pulled until 38% is achieved as directed by EPA personnel; biosolids failing to realize a 38% reduction (i.e. between testing) is incorporated into the ground within six hours. All samples were above 38% for this year.






    Lead Nickel

    Copper Zinc

    B io

    so lid

    s m

    et al

    s co

    nc en

    tr at

    io n

    (m g/

    kg )

    2015 Biosolids Metals

    Regulatory Limit mg/kg Jan-15 Mar-15 May-15 Aug-15 Sep-15 Dec-15

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    To provide biosolids that meets the applicable standards for their intended use or disposal, the Richmond Biosolids program is built around the concept of beneficial reuse of nutrients contained within the biosolids produced from our treatment process. During 2015, we recycled 23383 tons of class B biosolids for our agricultural customers in rural Virginia.

    The City of Richmond Biosolids quality meets or surpasses the applicable regulatory compliance requirements, as mentioned in the chart above.


    The WWTP has implemented the Biosolids Management Program that includes a method of internal audit and independent third-party verification to ensure effective ongoing biosolids operations. AUDIT FINDING

    In November 2015, the NSF-International Strategic Registrations conducted the Re-verification audit, the lead auditor recommended that Richmond maintains its platinum NBP certification.

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    Audit’s results and action taken in response to the audit results:

    As a result of the 2015 audit there were no major nonconformance, 9 minor non- conformances and 9 opportunities for improvement. The table below summarizes the Re-verification audit’s results and the actions taken:

    Audit Observation or Opportunity for Improvement Action Taken

    Requirement 2.1 - Minor Nonconformance – The organization is committed to the Code of Good Practice. Incorporated in that Code is a commitment to compliance with all federal, state and local requirements regarding use and disposal of biosolids away from the facility. Biosolids that are to be land applied must meet strict regulations and quality standards. The Part 503 rule governing the use and disposal of biosolids contain numerical limits for metals in biosolids, pathogen reduction standards, site restriction, crop harvesting restrictions and monitoring, record keeping and reporting requirements for land applied biosolids. In the General Provisions (Subpart A) it states that either the Class A or Class B pathogen requirements must be met when sewage sludge is applied to the land or placed on a surface disposal site. In April 2015 the biosolids discharged from the Richmond Wastewater Treatment plant digester had not met the time and temperatures regulatory requirement for either Class A or Class B pathogen reduction. Therefore these solids did not meet the requirements for land application. They were, however, land applied. While they were incorporated into the soil within six hours of land application this does not meet the requirements for pathogen reduction.

    CAR Ref: 103- The City land application contractor sent a notification letter on 11/20/15 to Department of environmental quality. The letter describes the digesters temperature issue that the City had in April 2015. The plant manager called DEQ to confirm the low temperature issue.

    The BMP team will establish a Standard Operating Procedure for handling biosolids that do not meet class B requirements.

    Requirement 4.2 – Minor Nonconformance – No procedure was found that specifies how biosolids, which do not meet the pathogen reduction requirement for Class B biosolids, are to be handled.

    CAR Ref: 104- The BMP team will establish a Standard Operating Procedure for handling biosolids that do not meet class B requirement by the end of December year.

    Requirement 5.2 – Opportunity for improvement – Operations personnel identified the leading single root cause of operation and maintenance problems throughout the biosolids value chain as grit (and non- biodegradable organics such as fibers). Grit wears

    CAR Ref: 105- The BMP team will discuss this opportunity to improve the grit removal with the sewer maintenance, operation managers and all

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    on all moving equipment, such as pumps, centrifuges, flights, screw conveyors, etc. It also causes frequent failure of all those pieces of equipment, which requires extensive resources for maintenance and repair. Grit and fibers also substantially reduce digester capacity and efficiency, and requires digesters to be taken out of service for maintenance more frequently than would otherwise be required. Consider establishing a goal and objective for eliminating grit and non-biodegradable organics.

    interested parties. In the next BMP meeting, we will study the SMART criteria for this goal.

    Requirement 5.2 – Opportunity for improvement – Consider establishing a goal and objective to have all the large sewers routinely cleaned on an annual schedule to remove grit and debris to reduce maintenance costs associated with pumping and lif

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