HomeMy WebLinkAbout20110030.tiff 400Wes U,. Engl woo , Co Avenue
1
Englewood, CO 80110
303-914-1445(Phone)
WASTE MANAGEMENT 303-914-9937(Fax)
Weld County Planning Department
GREELEY OFFICE
December 17, 2010
our 2 221110
Air Pollutey ion
onf RECEIVED
Air Pollution Control Division (APCD-SS-B1) 4Y/
Colorado Department of Public Health and Environment
4300 Cherry Creek Drive South
Denver, CO 80246-1530
Certified Mail
7006 2150 0004 4548 9058
RE: ANNUAL NMOC EMISSION RATE REPORT
NORTH WELD LANDFILL
Dear Ms. Shoaf,
As required under the State Emissions Guideline Program for municipal solid waste landfills, attached is
the 2010 Annual NMOC Emission Rate Report for North Weld Landfill (NWLF) located at 40,000 County
Road 25, Ault, Colorado.
40 CFR 60.754(a) provides two equations for determining NMOC emission rates. One equation is for
sites with unknown (estimated) solid waste acceptance rates, which is what the site heretofore has used
for calculating the emission rate at the facility. The other equation is for sites with known waste
acceptance rates (e.g., tonnage-based sites). For sites that include time periods with both known and
estimated acceptance rates, the Regulation indicates both equations should be used. The enclosed
Emission Rate Report reflects this change resulting from the installation of scales at the site on February
1, 2010. Page 1 of the report provides the emission rate calculation based on the estimated waste
volumes (for waste received prior to February 1, 2010), and Page 2 of the Report provides the emission
rate calculation for tons received at the site (for waste received after February 1, 2010).
As previously discussed with Dana Podell, this report covers the period of November 1, 2009 through
October 31, 2010. A revised report will be submitted no later than February 15, 2011 that will set a new
submittal schedule to occur based on the calendar year and cover the period January 1, 2010 through
December 31, 2010.
Should you have any questions regarding the information contained in this report, please contact me at
303-914-1445.
Sincerely,
p
Tom Schweitzer
Engineering Manager
Enclosure
cc: Troy Swain, WCDPHE
Kim Ogle, WCDPS
Jerry Henderson, CDPHE
Dana Podell, CDPHE
Bill Hedberg, NWLF
Bruce Clabaugh, Waste Management
2011-0030
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PLD777
2010 Tier 2 NMOC Emission Rate Report
North Weld Landfill
Prior to scale installation on February 1,2010,volume of waste accepted was estimated based on container size
of incoming waste. Therefore,because the actual year-to-year solid waste acceptance rate is estimated,
the equation found in 40 CFR 60.754(a)(ii)was used to determine NMOC emission rates for this time period.
MNMoc-2LOR(e"c-e")(DNMOC)(3.6 x 10-9)
NMOC Emission Rate for Years with Estimated Waste Acceptance Rates
MNMoc = Mass emission rate of NMOC,Mg/yr
Lo = Refuse methane generation potential,m6/Mg = 170.00 2
R = Average annual acceptance rate,Mg/yr = 122,534.25 1
k = Methane generation rate constant, 1/yr = 0.02 '
c = Years since closure,yrs = 0.00 a
(c=0 for active and/or new landfills)
= Age of landfill,yrs = 17.99
CNMOC = Concentration of NMOC,ppm as hexane = 153.00 2
Conversion factor = 3.6 x 10.9
MNMoc=2(L0)(R)(81"-e11tt)(Cnmoc)(3.6 x 10-) = :8.93 Mgfyr
1 Information used to determine annual average acceptance rate
The average annual acceptance rate(R)is determined by taking the total waste received between the approximate
opening date of February 3, 1992 and January 31,2010 divided by the number of years for this period.
Total tons received as of 01/31/10 4,584,717.63
Total tons converted to Mg5 4,159,228.55
Percent inert(including soil) 0.47
Total Mg less inert waste" 2,204,391.13
Age of site.as of 01/31/10 17.99
Annual average acceptance rate(Mg/yr) 122,534.25
2 For regulatory purposes,the EPA default values for Lo and CNMoc must be used to calculate Tier 1 NMOC
emission rates unless actual values have been obtained during Tier 2 sampling. NWLF conducted Tier 2
site specific sampling for CNMOC in 2008(using Method 25C)with a resulting concentration of 153 ppmV as hexane.
J For landfills in areas with a thirty year annual average precipitation of less than 25 inches,a k value of 0.02 is to be
used. Annual precipitation in the area of North Weld Landfill is about 13 inches,therefore a k value of 0.02 has been
used in the NMOC emission rate calculation.
Gas generation from waste accepted after January 31,2010 is calculated with"Known Waste Acceptance Rate"
NSPS equation.
5 Conversion Used:Tons to Mg-Divide tons by 1.1023
6 Inert material includes inert wastes that are disposed in the landfill as well as intermediate and final cover soil
used as part of routine landfill cell development.
NOTE: These calculations are made for MOPS purposes only. EPA has specifically stated as follows'."It is recommended that these default values not be used
for estimating landfill emissions for purposes other than NSPS and EG" (61 FR 9905,9912,March 12,1996). Consequently,these emission calculations grossly
overestimate actual and potential emissions end reviewers of this document are specifically cautioned against improper and irresonsible uses of these calculations.
Page 1 of 2 NWLF NMOC Tier 2 Report 2010.xls
2010 Tier 2 NMOC Emission Rate Report
North Weld Landfill
40 CFR 60/54(a)provides two equations for determining NMOC emission rates;one for sites with known solid waste acceptance
rates and another for sites with unknown(i.e.estimated)waste acceptance rates. For sites that include time periods with both
known and unknown acceptance rates,the Regulation indicates that both equations should be used. North Weld Landfill
is such a facility. Accordingly,this Emission Rate Report applies both equations for calculating the facility's 2010 Tier 2
NMOC emission rate.
NMOC Emission Rate Calculations for Years with Known Waste Acceptance Rates
The site installed scales on February 1,2010. Therefore,the equation found in 40 CFR 60.754(a)(1)(I)for known waste acceptance
was used to determine NMOC emission rates for this time period. The equation is provided below:
MNMoC=Summation of[2kLfMl(e'ti)(CNMoc)(3.6 x 10"9)]for each year with a known waste acceptance rate
MNMoc = Mass emission rate of NMOC,Mg/yr
k = Methane generation rate constant, 1/yr = 0.02 1
Lo = Refuse methane generation potential,m'/Mg = 170.00 2
Mi = Mass of solid waste received for given year, Mg = Varies per year(see table below)
ti = Age of the i n section,Years = current year minus year of waste placement
CNMOC = Concentration of NMOC,ppm as hexane = 153.00 2
Conversion factor = 3.6 x 10-9
NMOC Emission Rate Calculation Summary(for years with known waste acceptance rates]
Tons Tons Less
Year Received Inert Waste' Mi* tl MNMOC
02/01-10/31/2010 578,688 306,704 278,240 0 1.04
2011
2012
2013
Totals 578,688 306,704 278,240 1.04 Mg/yr •
`Conversion Used: tons to Mg-divide tons by 1.1023
1 For landfills in areas with a thirty year annual average precipitation of less than 25 inches,a k value of 0.02 is to be
used. Annual precipitation in the area of North Weld Landfill is about 13 inches,therefore a k value of 0.02 has been
used in the NMOC emission rate calculation.
2 For regulatory purposes,the EPA default values for Lo and CNMOC must be used to calculate Tier 1 NMOC
emission rates unless actual values have been obtained during Tier 2 sampling. NWLF conducted Tier 2
site specific sampling for CNMOC in 2008(using Method 25C)with a resulting concentration of 153 ppmV as hexane.
'Inert material includes inert wastes that are disposed in the landfill as well as intermediate and final cover soil
used as part of routine landfill cell development. 40 CFR 60.754(a)allows the mass of nondegradable material to
be subtracted from the total mass of solid waste when calculating the value of R.
NOTE: These calculations are made Mr NSPS purposes only. EPA has specifically stated as follows."It is recommended that these default values not be used
for estimating landfill emissions for purposes other than NSPS and EG" (61 FR 9995,9912,March 12,1996). Consequently,these emission calculations grossly
overestimate actual and potential emissions and reviewers of this document are specifically cautioned against improper and irresponsible uses of these calculations.
TOTAL NMOC EMISSION RATE: NMOC rate for years with known waste acceptance rates: 1.04
NMOC rate for years with estimated waste acceptance rates: 6.93
Combined NMOC Emission Rate: .-[71$ M9/Yr
Page 2 of 2
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2400 Wes Union Avenue
1
Englewood, CO 80110
303-914-1445(Phone)
WASTE MANAGEMENT 866-442-0285(Fax)
Weld County Planning Department
GREELEY OFFICE
'4N 14 ?nit
January 11, 2011 RECE V ED
Mr. Jerry Henderson
Colorado Department of Public Health and Environment
Hazardous Materials and Waste Management Division
HMWMD-SWIM-B2
4300 Cherry Creek Drive South
Denver, CO 80246-1530
Mr. Troy Swain
Weld County Department of Public Health and Environment
1555 N. 17th Avenue
Greeley, CO 80631
SUBJECT: NORTH WELD LANDFILL
FOURTH QUARTER 2010 GAS MONITORING REPORT
Dear Mr. Henderson and Mr. Swain:
Enclosed for your information is the Fourth Quarter 2010 Gas Monitoring Report for North Weld
Landfill (NWLF). The report dated December 17, 2010 was prepared by AquAeTer and
documents their field monitoring activities conducted on December 3, 2010. The gas monitoring
report contains monitoring results from the Phase 1 and 2 perimeter soil gas probes GP-06, GP-07,
GP-10 through GP-20, structure probes GP-01 and GP-02, inside the shop and office, and
confined spaces in the vicinity of the western boundary of the site. A map showing the gas probe
locations, the scale house and maintenance shop is included as Figure 1.
Section 2.3.1 of the Regulations Pertaining to Solid Waste Sites and Facilities, 6 CCR 1007-2, Part
1 (Regulations) requires that the concentration of explosive gases shall not exceed (A) 25% of the
lower explosive limit (LEL) (1% by volume in air for methane) within facility structures, and (B) the
LEL (5% by volume in air for methane- i.e., percent methane) at the facility boundary.
During this monitoring event, methane was detected in perimeter probe GP-10 at a concentration
of 13.6% and in structure probe GP-01 at a concentration of 6.3%. Combustible gas above
regulatory limits was not detected in any of the other probes, shop, office or confined spaces.
Probe GP-06 registered the presence of combustible gas, but below regulatory limits, with a
concentration of 0.4%.
The facility is currently operating under an approved gas remediation plan prepared in response to
elevated gas concentrations in structure probe GP-01 and perimeter probes GP-10 and GP-11.
The plan includes monthly monitoring of these probes and utility corridor access points along WCR
t?orvuvu..n;ca ,en,:.- i-ay-aCl) toll-0O3O
—PLO-1-1-1
•
Letter Jerry Henderson and Troy Swain
January 11, 2011
Page 2
25. Included in Attachment 1 are the July and August 2010 monthly reports. A summary of the
test results for these monthly events is provided in the following table.
CH4 Concentration
Monitoring Probe October 2010 November 2010
GP-01 11.1 7.6
GP-10 11.8 12.5
GP-11 0.0 0.1
Methane was not observed in the utility corridor access points or facility structures during the
monthly monitoring.
The approved remediation plan also included the installation of passive gas vents in waste along
the western limit of the disposal area. As stated in the plan, the passive vents, which were installed
in December 2009, may require one or more years to show consistent reduction in methane
concentrations at perimeter probes GP-10 and GP-11 and structure probe GP-01. Until methane
concentrations are below the regulatory threshold for three consecutive monthly events, monthly
monitoring will continue to be performed.
Continuous methane monitors are in operation within the facility maintenance building, office and
gatehouse and no methane detections have been observed.
If you have any questions regarding this report, please contact me at (303) 914-1445.
Sincerely,
On behalf of North Weld Landfill
Tom Schweitzer
Engineering Manager
cc: Kim Ogle, WCDPS, w/o enc.
Bill Hedberg, NWLF
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