CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD

CENTRAL VALLEY REGION

 

ORDER NO. 98-186

 

WASTE DISCHARGE REQUIREMENTS

FOR

CLOSURE OF

CITY OF COLFAX

CLASS III LANDFILL

PLACER COUNTY

 

The California Regional Water Quality Control Board, Central Valley Region, (hereafter Board) finds that:

 

1. The City of Colfax (hereafter Discharger) owned and operated a Class III landfill in the town of Colfax. The site was previously regulated by Waste Discharge Requirements (WDRs) Order No. 94-219. The Discharger submitted a Report of Waste Discharge (RWD) on 19 May 1997 and amendments to the RWD dated 31 July 1997, 17 October 1997, 9 March 1998 and 15 June 1998. The RWD describes the proposed closure of the landfill and requests approval of an engineered alternative design.
2. The landfill is on 16.5 acres on Iowa Hill Road, in the NE-1/4 of the SW-1/4 of Section 2, T14N, R9E, MDB&M, as shown in Attachment A, which is incorporated herein and made a part of this Order.
3. The landfill was operated by the City of Colfax from the early 1960s until it ceased accepting wastes in 1988. The waste is confined to 3 acres of the property, as shown in Attachment B, which is incorporated herein and made part of this Order. The site continues to be maintained by the City of Colfax. Since the landfill ceased accepting waste prior to October 9, 1991, the landfill is not subject to 40 CFR 258 (Subtitle D) federal solid waste regulations.
4. Refuse disposal was done by the trench-and-cover method. The landfill accepted residential and commercial solid wastes. These wastes are classified as non-hazardous solid wastes as described in Section 20220 of Title 27, California Code of Regulations (CCR), Division 2, Subdivision 1 (Title 27). Less than 100,000 cubic yards of waste have been disposed of at the site.
5. The facility was previously regulated by Waste Discharge Requirements (WDRs) Order No. 94-219. Waste discharge requirements are being revised to incorporate the minimum performance goals and prescriptive standards contained in Title 27, for the landfill's closure and postclosure maintenance and monitoring of the landfill.
6. The site has experienced recurring problems with the generation of leachate, particularly in the mid-1980's while it was still receiving wastes. Off-site discharges of leachate were documented at least twice. A Notice of Violation of waste discharge requirements was issued by the Board in 1986 in response to leachate seeping into a tributary to Slaughter Ravine. A 1989 Board staff inspection noted that the landfill was still in violation of WDRs due to the off-site discharge of leachate. In an effort to reduce the generation of leachate, in 1989 the Discharger placed a 4 to 18 foot thick low-permeability interim cover of native soil. Leachate seeps have been observed since the interim cover has been placed.
7. A Closure and Post-Closure Maintenance Plan for this facility proposed a low permeability asphalt concrete barrier layer with a permeability on 1 x 10^-9 cm/sec on the top deck as an engineered alternative. Drainage improvements and erosion control will be done on the steep side slopes in order to reduce infiltration and avoid leachate seeps.

 

SITE DESCRIPTION

8. The landfill is on an east-facing canyon slope in the foothills on the west side of the Sierra Nevada Mountains. The site is underlain by metasedimentary and metavolcanic rocks belonging to the Mariposa Formation. Soils in the area are developed to a thickness ranging from 2" to 18". Regional Board staff observations in 1986 reported one or more springs above the landfill site.
9. Land within 1000 feet of the facility consists of forests and rural housing.
10. Ground water levels beneath the landfill are about 1,950 feet above mean sea level (MSL) for the downgradient wells and 2,290 feet above MSL for the upgradient well. The ground water flow direction is east-southeast with a gradient of 0.31 feet/feet. The beneficial use of ground water is primarily agricultural irrigation with limited domestic supply.
11. Surface drainage from this site flows via an unnamed creek into Slaughter Ravine, a tributary to the North Fork of the American River.
12. The beneficial uses of Slaughter Ravine and North Fork American River are domestic, municipal and agricultural supply; fishing; propagation and sustenance fish and aquatic life; wildlife and stock watering; contact and non-contact recreation; and esthetics.
13. The site is not within the 100 year floodplain.
14. The facility receives a maximum of 60 inches and a minimum of 35 inches of precipitation per year (USDA, 1980).
15. Water quality monitoring in the downgradient monitoring wells indicates a release from the landfill with continued elevated concentrations of sulfate and chloride. The Discharger proposes to close the landfill as a corrective action. Construction of a low permeability barrier layer over the landfill will prevent infiltration of precipitation into the wastes which has impaired groundwater quality and generated leachate.

 

ENGINEERED ALTERNATIVE

16. The Discharger proposes to install a low permeability asphalt concrete barrier layer with a permeability on 1 x 10^-9 cm/sec on the top deck as an engineered alternative. The low permeability asphalt concrete cap consists of a fluid-asphalt impregnated geotextile sandwiched between 1-1/2 inches of asphalt concrete on either side, overlying a 4 inch thick crushed rock base with penetration coat. In areas on the top deck overlying wastes, the rock base will be separated from the foundation layer with a geotextile.

CEQA CONSIDERATIONS

17. The City of Colfax adopted a Final Mitigated Negative Declaration (FMND) on 11 August 1998 for the final closure project in accordance with the provisions of the California Environmental Quality Act, (Public Resources Code, Section 21000, et seq.) The FMND determined that the proposed project may have potentially significant effects on the environment, but that these effects can be mitigated to be less than significant. These potentially significant effects are increased erosion during construction, altered drainage patterns and increased stormwater runoff and discharge velocities after closure. The drainage system and erosion control measures have been designed to mitigate these potentially significant effects to less than significant effects.

 

CERTIFICATION

18. A registered civil engineer will certify that closure of the Landfill meets the construction or prescriptive standards and performance goals, including siting, design of liners, LCRSs, precipitation & drainage controls, covers, caps, etc., and considerations of seismic and flood safety of Title 27.

 

OTHER LEGAL REFERENCES

19. This Order implements

 

1. the Water Quality Control Plan for the Sacramento River and San Joaquin River Basin Third Edition; and
2. the prescriptive standards and performance goals of California Code of Regulations, Title 27, Division 2, Subdivision 1 Solid Waste Requirements (Title 27) and subsequent revisions.

 

PROCEDURAL REQUIREMENTS

 

20. All local agencies with jurisdiction to regulate land use, solid waste disposal, air pollution, and to protect public health have approved the use of this site for the discharges of waste to land stated herein.
21. The Board has notified the Discharger and interested agencies and persons of its intention to update the WDRs for this facility.
22. In a public hearing, the Board heard and considered all comments pertaining to this facility and discharge.

 

IT IS HEREBY ORDERED that Order No. 94-219 is rescinded and is further ordered that the City of Colfax, its agents, successors and assigns, in order to meet the provisions of Division 7 of the California Water Code and the regulations adopted thereunder, shall comply with the following:

 

A. PROHIBITIONS

1. The discharge of additional waste of any kind at this facility is prohibited.
2. The discharge of solid or liquid waste or leachate to surface waters, surface water drainage courses, or ground water is prohibited.
3. The discharge of waste to ponded water from any source is prohibited.
4. The discharge of waste within 100 feet of surface waters is prohibited.

 

B. DISCHARGE SPECIFICATIONS

1. Water used for facility maintenance shall be limited to the minimum amount necessary for dust control, construction, and proper compaction of clay liners and covers.
2. Neither the treatment nor the discharge of wastes shall cause a pollution or nuisance as defined by the California Water Code, Section 13050.
3. The discharge of wastes shall not cause degradation of any water supply.

 

C. FACILITY SPECIFICATIONS

General Specifications

1. All wells within 500 feet of a waste management unit shall be sealed or abandoned to the satisfaction of the Placer County Department of Environmental Health prior to the discharge of waste to the unit. A record of the sealing and/or abandonment of such wells shall be sent to the Board and to the State Department of Water Resources.
2. Leachate generation by a landfill unit LCRS shall not exceed 85 percent of the design capacity of the sump pump. If leachate generation exceeds this value or if the depth of fluid in an LCRS exceeds the minimum needed for safe pump operation, then the Discharger shall notify the Board in writing within seven days. Notification shall include a timetable for remedial or corrective action necessary to reduce leachate production.

 

General WMU Construction

3. A final construction report shall be submitted for acceptance by Board staff after completion of closure construction. The final closure construction report shall include, but not be limited to, as-built plans for the landfill, a CQA report with a written summary of the CQA program and all test results, analyses, and copies of the inspector's original field notes, and a certification as described in the Standard Provisions and Reporting Requirements.

 

Protection From Storm Events

4. Closure construction shall be accomplished in such a manner as to prevent inundation or washout due to floods with a 100 year return period. Landfill-related containment structures shall be constructed and maintained to prevent, to the greatest extent possible, ponding, infiltration, inundation, erosion, slope failure, washout, and overtopping under 100 year, 24-hour precipitation conditions. Surface drainage from tributary areas and internal site drainage from surface or subsurface sources shall not contact or percolate through wastes.
5. Annually, prior to the anticipated rainy season but no later than 1 November, any necessary erosion control measures shall be implemented, and any necessary construction, maintenance, or repairs of precipitation and drainage control facilities shall be completed to prevent erosion or flooding of the facility and to prevent surface drainage from contacting or percolating through wastes.
6. Precipitation and drainage control systems shall be designed, constructed and maintained to accommodate the anticipated volume of precipitation and peak flows from surface runoff under 100-year, 24-hour precipitation conditions.
7. Landfills shall be designed, constructed and operated in compliance with precipitation and flood conditions contained in the Standard Provisions and Reporting Requirements referenced in Provision F.3., below.

 

D. CLOSURE SPECIFICATIONS:

Landfill Closure

1. The Discharger has proposed to close the landfill under the following closure schedule:

Phase	Description	Compliance Date
1	Foundation layer on top deck and side slopes	15 October 1999
2	Asphalt concrete cover on top deck and public access road	15 October 2001
3	Erosion control hand work on lower slopes and removal of surface waste	15 October 2003
4	Install leachate collection system, if necessary	15 October 2006
5	Install clay barrier layer on side slopes, if necessary	15 October 2013

 

If corrective action monitoring indicates that wastes are still degrading groundwater or if Phases 1 through 3 fail to prevent leachate seeps on the side slopes, then the Discharger shall implement Phases 4 through 5.

 

2. Methane and other landfill gases shall be adequately monitored and controlled to prevent the danger of explosion, adverse health effects, nuisance conditions, or the impairment of beneficial uses of water.
3. Landfill leachate shall be collected and disposed in a manner approved by the Regional Board Executive Officer.
4. Landfill closure shall be under the direct supervision of a California registered civil engineer or certified engineering geologist.
5. The closed landfill shall be provided with at least two permanent monuments, installed by a licensed land surveyor and/or California registered civil engineer, from which the location and elevation of all wastes, containment structures, and monitoring facilities can be determined throughout the post-closure maintenance period.
6. The closed landfill shall receive a final cover which is designed and constructed to function with minimum maintenance and consists of a fluid-asphalt impregnated geotextile sandwiched between 1-1/2 inches of asphalt concrete on either side, overlying a 4 inch thick crushed rock base with penetration coat on the top deck overlaying a two foot foundation layer, or, at a minimum, of a two-foot thick foundation layer of materials with appropriate engineering properties, overlain by a one-foot thick clay layer, and finally by a one-foot thick vegetative soil layer.
7. If an asphalt-concrete cap is installed, it shall have a maximum hydraulic conductivity of 1 x 10-9 cm/sec. If a compacted clay cap is installed, it shall have a minimum relative compaction of 90 percent and a maximum hydraulic conductivity of 1 x 10-6 cm/sec. Hydraulic conductivities of liner materials shall be determined by laboratory test using solutions with similar properties as the fluids that will be contained. Hydraulic conductivities of cap materials shall be determined by laboratory tests using water. Hydraulic conductivities determined through laboratory methods shall be confirmed by approved field testing of the finished liner. Construction methods and quality assurance procedures shall be sufficient to ensure that all parts of the liner and cap meet the hydraulic conductivity, moisture content, and compaction requirements. Proposed design parameters (e.g., soil type, Atterburg limits, moisture content, relative compaction), construction methods and quality assurance procedures for clay liners shall be used in the construction of a test pad prior to liner construction to ensure adequacy of the design, construction and testing methods.
8. Prior to the construction of any landfill cap, a construction quality assurance plan shall be submitted and approved by Regional Board staff.
9. Repair of existing closure construction must, at a minimum, comply with the existing approved construction plans.
10. Vegetation shall be planted and maintained over the closed landfill. Vegetation shall be selected to require a minimum of irrigation and maintenance and shall have a rooting depth not in excess of the vegetative layer thickness.
11. The closed landfill area shall be graded to at least a three percent grade and maintained to prevent ponding.
12. Areas with slopes greater than ten percent, surface drainage courses, and areas subject to erosion by wind or water shall be designed and constructed to prevent such erosion.
13. All containment structures shall be designed and constructed under the direct supervision of a California registered civil engineer or certified engineering geologist and shall be certified by that individual as meeting the prescriptive standards and performance goals of Title 27 prior to waste discharge.

E. RECEIVING WATER LIMITATIONS

Water Quality Protection Standard

The concentrations of Constituents of Concern in waters passing through the Points of Compliance shall not exceed the Concentration Limits established pursuant to Monitoring and Reporting Program No. 98-186, which is attached to and made part of this Order.

 

F. PROVISIONS

1. The Discharger shall, in a timely manner, remove and relocate any wastes discharged at this facility in violation of this Order.
2. The Discharger shall notify the Board in writing of any proposed change in ownership or responsibility for the facility. This notification shall be given 90 days prior to the effective date of the change.
3. The Discharger shall comply with the Standard Provisions and Reporting Requirements, dated August 1997, which are hereby incorporated into this Order. The Standard Provisions and Reporting Requirements contain important provisions and requirements with which the Discharger must comply. A violation of any of the Standard Provisions and Reporting Requirements is a violation of these waste discharge requirements.
4. The Discharger shall comply with all applicable provisions of Title 27 CCR and 40 CFR, Part 258, that are not specifically referred to in this Order.
5. The Discharger shall comply with Monitoring and Reporting Program No. 98-186, which is attached to and made part of this Order. This compliance includes, but is not limited to, maintenance of waste containment facilities and precipitation and drainage controls and monitoring groundwater, leachate from the landfill units, the vadose zone and surface waters, throughout the active life of the waste management units and the post-closure maintenance period. A violation of Monitoring and Reporting Program No. 98-186 is a violation of these waste discharge requirements.
6. The Discharger shall maintain legible records of the volume and type of each waste discharged at each landfill and the manner and location of the discharge. Such records shall be maintained at the facility until the beginning of the post-closure maintenance period. These records shall be available for review by representatives of the Board and of the State Water Resources Control Board at anytime during normal business hours.
7. The Discharger shall maintain waste containment facilities and precipitation and drainage controls, and shall continue to monitor ground water, leachate from the landfill unit, the vadose zone, and surface waters per Monitoring and Reporting Program No. 98-186 throughout the post-closure maintenance period.
8. The post-closure maintenance period shall continue until the Board determines that remaining wastes in the landfill will not threaten water quality.
9. The owner of the waste management facility shall have the continuing responsibility to assure protection of usable waters from discharged wastes and from gases and leachate generated by discharged waste during the closure and post-closure maintenance period of the landfill and during subsequent use of the property for other purposes.
10. The Discharger shall complete the tasks outlined in Discharge Specification D.1. in these WDRs in accordance with the following time schedule:

 

Task	Compliance Date
Submit design plans, specifications, construction schedule, and quality assurance plan for each phase	3 months prior to start of closure construction work
Submit as-built plans, construction quality assurance, and closure certification report for each phase	within 1 month after completion of closure construction

 

12. The Discharger shall provide proof to the Board within sixty days after completing final closure that the deed to the landfill facility property, or some other instrument that is normally examined during title search, has been modified to include, in perpetuity, a notation to any potential purchaser of the property stating that:

 

1. the parcel has been used as a municipal solid waste landfill (MSWLF);
2. land use options for the parcel are restricted in accordance with the post-closure land uses set forth in the post-closure plan and in WDRs for the landfill; and
3. in the event that the Discharger defaults on carrying out either the post-closure maintenance plan or any corrective action needed to address a release, then the responsibility for carrying out such work falls to the property owner.

 

13. The Board will review this Order periodically and will revise these requirements when necessary.

 

G. REPORTING REQUIREMENTS

1. The Discharger shall maintain a closure and post-closure maintenance plan (or submit suitable modifications to a pre-existing plan), that complies with Title 27 of the CCR.
2. The Discharger shall notify the Board of any material change in the landfill closure plans. This notification shall be given 90 days prior to the effective date of the change and shall be accompanied by any technical documents that are needed to demonstrate continued compliance with these WDRs.
3. The Discharger shall submit financial assurances for a reasonably foreseeable release by 1 July 1999 and a status report regarding the financial assurances every five years thereafter that either validates the ongoing viability of the financial instrument or proposes and substantiates any needed changes.
4. The Discharger shall immediately notify the Board of any flooding, equipment failure, slope failure, or other change in site conditions which could impair the integrity of waste or leachate containment facilities or of precipitation and drainage control structures.

 

5. The Discharger shall notify the Board in writing of any proposed change in ownership or responsibility for construction or operation of the facility. The Discharger shall also notify the Board of a material change in the character, location, or volume of the waste discharge and of any proposed expansions or closure plans. This notification shall be given 120 days prior to the effective date of the change and shall be accompanied by an amended Report of Waste Discharge and any technical documents that are needed to demonstrate continued compliance with these waste discharge requirements.

 

I, GARY M. CARLTON, Executive Officer, do hereby certify that the foregoing is a full, true, and correct copy of an Order adopted by the California Regional Water Quality Control Board, Central Valley Region, on 11 September 1998.

 

 

 

_________________________________

GARY M. CARLTON, Executive Officer

 

AMENDED

rae/lsb:colfax.wdr

CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD

CENTRAL VALLEY REGION

 

MONITORING AND REPORTING PROGRAM NO. 98-186

FOR

CLOSURE OF

CITY OF COLFAX

CLASS III LANDFILL

PLACER COUNTY

 

The Discharger shall maintain water quality monitoring systems that are appropriate for detection and corrective action monitoring and that comply with the provisions of Title 27, California Code of Regulations (CCR), Division 2, Subdivision 1, Chapter 3, Subchapter 3.

Compliance with this Monitoring and Reporting Program, and with the companion Standard Provisions and Reporting Requirements, is ordered by Waste Discharge Requirements Order No. 98-186. Failure to comply with this Program, or with the Standard Provisions and Reporting Requirements, constitutes non-compliance with the WDRs and with the Water Code, which can result in the imposition of civil monetary liability.

 

A. REPORTING

The Discharger shall report monitoring data and information as required in this Monitoring and Reporting Program and as required in the Standard Provisions and Reporting Requirements. Reports which do not comply with the required format will be REJECTED and the Discharger shall be deemed to be in non-compliance with the WDRs. In reporting the monitoring data required by this program, the Discharger shall arrange the data in tabular form so that the date, the constituents, the concentrations, and the units are readily discernible. The data shall be summarized in such a manner so as to illustrate clearly the compliance with waste discharge requirements or the lack thereof. Historical and current monitoring data shall be graphed at least once annually. Graphs for the same constituent shall be plotted at the same scale to facilitate visual comparison of monitoring data. A short discussion of the monitoring results, including notations of any water quality violations, shall precede the tabular summaries.

Field and laboratory tests shall be reported in the semi-annual monitoring reports. Method detection limits and practical quantitation limits shall be reported. All peaks shall be reported, including those which cannot be quantified and/or specifically identified. Quarterly, semiannual, and annual monitoring reports shall be submitted to the Board by the 15th day of the month following the calendar quarter in which the samples were taken or observations made. The results of any monitoring done more frequently than required at the locations specified herein shall be reported to the Board.

An annual report shall be submitted to the Board by 15 January of each year containing both tabular and graphical summaries of the monitoring data obtained during the previous year. The Discharger may combine this information with the fourth quarter monitoring report for the facility.

 

B. REQUIRED MONITORING REPORTS

1. Water Quality Protection Standard Report

The Discharger shall develop water quality protection standards and submit them in the Annual Monitoring Summary Report.

 

2. Detection Monitoring and Corrective Action Report

The facility is currently under Detection and Corrective Action Monitoring. The Discharger shall submit reports of the results of Detection and Corrective Action Monitoring in accordance with the schedules specified in this Monitoring and Reporting Program.

 

3. Annual Monitoring Summary Report

The Discharger shall submit the Annual Monitoring Summary Report as specified in the Standard Provisions and Reporting Requirements and in this Monitoring and Reporting Program.

 

4. Constituents-of-Concern 5 Year Monitoring Program

The Discharger shall sample all Monitoring Points and Background Monitoring Points for each monitored medium for all Constituents of Concern (COCs) every fifth year, beginning with calendar year 1999 (the first Reporting Period ends 30 September 1999, with subsequent COC monitoring efforts being carried out every fifth year thereafter.

 

5. Constituents-of-Concern (COC) Leachate Detection Report

The Discharger shall report to the Board by no later than 1 March of each year the analytical results of the leachate sample taken the previous Fall, including an identification of all detected COCs in Table 1 (below) and the constituents identified.

 

Standard Observations

Each monitoring report shall include a summary and certification of completion of all Standard Observations for the waste management unit, for the perimeter of the landfill, and for the receiving waters. The standard observations shall be performed on a monthly basis and shall include those elements as defined in the Standard Provisions and Reporting Requirements. The monitoring reports shall also include copies of the Discharger's inspection reports for the semi-annual period in which the facility was inspected. A copy of the annual testing of the LCRS for the waste management units shall also be submitted in the annual monitoring report.

 

C. MONITORING

If the Discharger, through a detection monitoring program, or the Board finds that there is a measurably significant increase in indicator parameters or waste constituents over the water quality protection standards at or beyond the Points of Compliance, the Discharger shall notify the Board or acknowledge the Board's finding in writing within seven days, and shall immediately resample for the constituent(s) or parameter(s) at the point where the standard was exceeded. Within 90 days, the Discharger shall submit to the Board the results of the resampling and either:

a. a report demonstrating that the water quality protection standard was not, in fact, exceeded; or

b. an amended Report of Waste Discharge for the establishment of an evaluation monitoring program, per Section 20415 and 50425 of Title 27, which is designed to evaluate changes in water quality due to the release from the landfills.

D. REQUIRED MONITORING PROGRAMS

1. Groundwater Monitoring

The following monitoring program shall be implemented at the facility to determine compliance with the "water quality protection standards" and to monitoring impacts to the groundwater. The monitoring network shall consist of background monitoring well MW-1 and downgradient monitoring wells MW-2, MW-3, and MW-4. Replacement wells or alternative monitoring wells to be sampled must be approved by staff before changes to this monitoring and reporting schedule can be made.

 

Each monitoring well shall be purged three times its well volume or until dry prior to sampling. Metal analysis shall be reported as dissolved (filtered). The Discharger is required to perform sampling, analysis, and observations according to the schedule in Table 1:

 

Table 1 - Groundwater Monitoring Program
Parameter	Units	Sampling Frequency
Field Parameters Temperature Groundwater Elevation Specific Conductance pH Turbidity Monitoring Parameters Total Dissolved Solids (TDS) Chloride Nitrate-nitrogen Sulfate Chemical Oxygen Demand Volatile Organic Compounds (EPA Method 8260) Constituents of Concern Dissolved Iron Manganese Metals	E C Ft. & hundredths, MSL m mhos/cm pH units NTB Turbidity Units   mg/l mg/l mg/l mg/l mg/l m g/l     mg/l mg/l mg/l	Quarterly Quarterly Quarterly Quarterly Quarterly   Semi-annual Semi-annual Semi-annual Semi-annual Semi-annual Semi-annual     Annual Annual Annual

 

2. Surface Water Monitoring

The Discharger shall sample upstream monitoring point SW-1 and downstream at monitoring point SW-2. The Discharger shall collect surface water samples after the first storm of the rainy season which produces significant flow and quarterly thereafter when water is present. The Discharger shall collect samples from all stations and analyze at the frequency as specified in Table 2 - Surface Water Monitoring Program. All monitoring points which are also monitoring stations for the storm water program monitoring shall be sampled on a semi-annual basis as part of the detection monitoring plan to monitor the potential for landfill impact on surface water.

The Discharger shall submit the surface water monitoring reports with the corresponding semi-annual groundwater monitoring reports. The Discharger shall include an evaluation of surface water quality impacts and compliance with the Water Quality Protection Standard. Surface water monitoring reports may be submitted with the annual storm water monitoring report and also included in the annual monitoring report submitted pursuant to this monitoring and reporting program. The Discharger shall continue to monitor storm water discharges in accordance with Water Quality Order No. 97-03-DWQ (Discharges of Storm Water Associated with Industrial Activities). All surface water monitoring shall comply with the Storm Water Pollution Prevention Plan.

 

TABLE 2 - SURFACE WATER MONITORING PROGRAM
Parameter	Units	Frequency
Field Parameters Temperature Specific Conductance pH Turbidity   Monitoring Parameters Total Suspended Solids (TSS)1 Total Dissolved Solids (TDS)1 Chlorides1 Sulfates1 Nitrate - Nitrogen1 Total Organic Carbon1 VOCs1 (EPA Method 8260)   Constituents of Concern Total Organic Carbon1 Dissolved Iron1 Manganese1 Metals1	°C µmhos/cm pH units Turbidity units     mg/L mg/L mg/L mg/L mg/L mg/L m g/l     mg/L mg/L mg/L mg/L	Semi-annual Semi-annual Semi-annual Semi-annual     Semi-annual Semi-annual Semi-annual Semi-annual Semi-annual Semi-annual Semi-annual     5-years 5-years 5-years 5-years
___________________ 1 - To be monitored quarterly for one year to determine a concentration limit

 

3. Leachate Monitoring

The landfill does not have a Leachate Collection and Removal System. If leachate surfaces, the Discharger shall immediately sample the leachate and continue to sample the leachate as specified in Table 3 - Leachate Monitoring Program. The quantity of leachate pumped from each sump shall be measured continuously and reported as Leachate Flow Rate (in gallons per day).

 

Table 3 - Leachate Monitoring Program
Parameters	Units	Sampling Frequency
Field Parameters Flow Rate Specific Conductance pH Monitoring Parameters Total Dissolved Solids (TDS) Chloride Nitrate-nitrogen Sulfate Chemical Oxygen Demand Volatile Organic Compounds (EPA Method 8260) Constituents of Concern Dissolved Iron Manganese Metals	gallons/day m mhos/cm pH units   mg/l mg/l mg/l mg/l mg/l m g/l     mg/l mg/l mg/l	Monthly Monthly Monthly   Quarterly Quarterly Quarterly Quarterly Quarterly Quarterly     Annual Annual Annual

 

E. WATER QUALITY PROTECTION STANDARDS

The Water Quality Protection Standard (Standard) shall consist of the following elements:

1. Constituents of Concern 4. Points of Compliance

2. Concentration Limits 5. Compliance Period

3. Monitoring Points

Each of these is described as follows:

1. Constituents of Concern

The ‘COC list' (list of Constituents of Concern required under 27 CCR 20395) shall include all constituents listed in Tables 1 and 2 and in Waste Discharge Requirements Order No. 98-186. The Dischargers shall monitor all COCs every five years, or more frequently as required under the corrective action monitoring program

 

2. Concentration Limits

The Discharger shall determine the Concentration Limit for any given Constituent of Concern or Monitoring Parameter in a given monitored medium(i.e., groundwater and surface water) at the landfill. The concentration limit shall be used as the basis of comparison with data from the Monitoring Points in that monitored medium. The concentration limit shall be determined as follows:

1. The mean (or median, as appropriate) and standard deviation (or other measure of central tendency, as appropriate) of the constituent's background data; or
2. The constituent's background value, established anew during each Reporting Period, shall be determined using only data from all samples collected during that Reporting Period from the Background Monitoring Points for that monitored medium. Either:

1) The mean (or median, as appropriate) and standard deviation (or other measure of central tendency, as appropriate) of the constituent's background data; or

2) The constituent's MDL, in cases where less than 10 percent of the background samples exceed the constituent's MDL; or

c. A concentration limit greater than background, as approved by the Board for use during or after corrective action.

3. Monitoring Points

Monitoring Points (including background) for groundwater and surface water detection monitoring are listed below:

Groundwater: MW-1, MW-2, MW-3, MW-4

Surface Water: SW-1, SW-2

4. Points of Compliance

The Points of Compliance are:

Groundwater: MW-2, MW-3, MW-4

Surface Water: SW-2

5. Compliance Period

The Compliance period is the number of years equal to the active life of the landfill plus the closure period. Each time the Water Quality Protection Standard is exceeded (i.e., a release is discovered), the surface impoundment or landfill begins a Compliance Period on the date the Board directs the Discharger to begin an Evaluation Monitoring Program. If the Discharger's Corrective Action Program (CAP) has not achieved compliance with the Standard by the scheduled end of the Compliance Period, the Compliance Period is automatically extended until the surface impoundment or landfill has been in continuous compliance for at least three consecutive years.

 

The Discharger shall implement the above monitoring program on the effective date of this Order.

 

 

 

Order by: __________________________________

GARY M. CARLTON, Executive Officer

 

_________11 September 1998

(Date)

 

AMENDED

rae/lsb:colfax.mrp

INFORMATION SHEET

 

 

CITY OF COLFAX

CLOSURE OF CLASS III LANDFILL

PLACER COUNTY

 

 

The Colfax Landfill is an unlined three-acre facility on a canyon slope in the foothills of the Sierra Nevada. The City of Colfax operated the landfill from the early 1960s until 1988. The landfill accepted residential and commercial non-hazardous solid wastes. Some interim cover has been applied to the landfill; however, the final cover is not yet in place.

 

This order requires the Discharger to close the landfill using an engineered alternative consisting of an asphalt concrete cap with a permeability of less than 1 x 10^-9 cm/sec as the barrier layer on the top deck. No barrier layer will be placed on the sides slopes unless the engineered alternative fails to reduce infiltration and prevent leachate seeps. If the engineered alternative fails, then the Discharger will install a two foot clay barrier layer on the upper portion of the side slope. The lower section is very steep and would require substantial work to construct a 3 (horizontal): 1 (vertical) slope. Drainage improvements and erosion control will be done on the side slope to reduce infiltration and avoid leachate seeps.

 

The construction schedule for closure of the landfill is approximately 15 years due to insufficient funds in the closure account and the limited funds raised annually for closure. The asphalt concrete cap will be completed by 2003 and, if necessary, a prescriptive standard cap will be completed on the upper side slopes by 2013.

These requirements rescind Order No. 94-219, approve an engineered alternative for closure of the landfill, approve a 15 year construction schedule, and provide for post-closure maintenance and monitoring.

 

There are four ground water monitoring wells which will be used for detection and corrective action monitoring. Water quality monitoring indicates that there has been a release from the landfill. The closure of the landfill will serve as the corrective action measures for impacts on water quality.

 

Surface water drainage from this site flows via an unnamed creek into Slaughter Ravine, a tributary to the North Fork of the American River.

 

 

 

 

 

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