HomeMy WebLinkAboutLandfill Stabilization Proposal Technical Memorandum
To: Timm Schimke, Deschutes County
From: Michael Greenberg P.E., HDR Project: Review of WTEG Proposal for
Steam Injection at Deschutes
Landfill
Copy: Joel Miller P.E., HDR
Date: June 3, 2013 Job No: 00102.0000195546
Re: Final Technical Memorandum
Executive Summary
HDR Engineering, Inc. (HDR) was retained by Deschutes County (County) to provide an
independent review analyzing the Waste to Energy Group, LLC’s (WTEG) proposal to inject
steam into the Deschutes County’s Knott Landfill (KLF) in order to increase the production of
landfill gas and subsequently refine the gas into pipeline quality methane (the “Project”). This
Technical Memorandum (TM) represents HDR’s review of the Project. HDR understands that
WTEG’s project description includes the following:
• A Piezo-Penetrometer Test (PPT) survey will be conducted by WTEG initially to
determine where to install gas collectors.
• A steam injection system including a landfill gas (LFG) collection system will be
engineered by WTEG based on the results of the PPT survey.
• WTEG will provide and use a Biogas Purification and Compression System
manufactured by Generon IGS, Inc., to process the raw LFG to product gas. Product
gas will be sold by WTEG to a buyer and injected into a natural gas pipeline adjacent to
the KLF facility.
• WTEG intends to enter into a binding agreement with the County to perform the project
as described.
This TM is organized with sections reviewing technical, permitting/regulatory, financial, and
contractual aspects of the Project, including an overview comparison to Non-Steam Bioreactors.
HDR’s findings are summarized as follows:
• Financial – It is HDR’s opinion that LFG generation and collection may be lower than
WTEG predicts, even if above typical bioreactor output. This may adversely affect the
financial pro-forma, resulting in potentially lower or negative results for the project as
depicted in sensitivit y cases modeled by HDR. This increases the importance of
contractual protections to the County. Based on the draft in-progress contract reviewed
by HDR and discussions with the County and WTEG we understand that WTEG intends
to finance the total capital and operations costs of the project, without any financial
obligation to the County. HDR recommends that the County only enter into the
agreement with WTEG if appropriate terms are negotiated protecting the County from
any financial responsibilities or liabilities should the project fail. This TM contains a
section (last section, Contractual Risks) with comments and recommendation regarding
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 2 of 33
the in-progress draft agreement reviewed by HDR and discussed with the County during
this project. Although HDR has reviewed and analyzed all available WTEG economic
information, for this report we have removed all of these economic figures as they are
proprietary to WTEG and their development efforts.
• Environmental – Based on the description of WTEG’s proposed processes, the
environmental risk to County appears to be relatively low. WTEG confirms that they will
install all LFG wells well above the landfill liner base grades. However, WTEG should
enhance its proposal to provide backup flare capability for all LFG collected. The County
should also confirm that WTEG assigns staff experienced in operating LFG systems and
monitoring in order to maintain air quality compliance. The WTEG expectation and
planning for a level of 99% LFG removal appears unrealistic, which relates both to
financial and environmental compliance aspects of the project. However, given that the
Oregon Department of Environmental Quality (DEQ) must apply monitoring
requirements to assure public health and safety under RD&D rules and the project will
involve limited sequential area in the injection operations, it is not expected to pose an
environmental risk 1 different than other landfills. This opinion is based on the
expectation that WTEG will apply appropriately experienced staff to the project such that
all applicable regulatory air quality compliance measures are met and attained over the
time of the project.
• Permitting – The Oregon DEQ was interviewed during preparation of this TM and
appears receptive to the project. There do not appear to be fatal flaws in the permitting
scheme given the RD&D authority held by the state. As holder of the permits the County
needs to be provided with accurate continual operational data from WTEG during all
periods of operations to be able to check that the gas generation is being properly
controlled and to provide for future control of the LFG. The County should reserve the
right to be supplied with information in addition that required by regulatory agencies.
This is recommended in the event if the project was to fail from financial, compliance or
other reasons the County could be forced to address any remaining compliance or
liability issues.
• Operational – Based on the information provided to HDR regarding the proposed
project, it appears that WTEG did not propose to provide the County with a working gas
collection system after WTEG leaves each 4-acre tract. The County will be relying upon
WTEG’s assertion that all or effectively most gas has been extracted from each 4-acre
tract. However, there remains the possibility that once WTEG leaves an area, fugitive
gas emissions could be higher than prior to the project (due to the effects of the steam
injection). Similar to a conventional bioreactor, the WTEG process will be injecting liquid
(steam) into the waste mass. Typical bioreactors require that operations are carefully
controlled to avert the potential for overloading of the leachate collection system and/or
the possibility of slope stability and side-slope leachate outbreaks, which generally
increase over a typical dry cell landfill. WTEG has reported that the proposed steam
1 HDR’s scope of services and review did not include any health risk assessment or detailed environmental modeling
of the proposed project. It is assumed that applicable regulations would protect public health and safety to
appropriate levels.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 3 of 33
injection process will use less liquid, however, the information WTEG provided to HDR
regarding the proposed project report liquid requirements similar to bioreactor
operations2. Therefore, WTEG’s process could potentially carry the same operational
risks as a conventional bioreactor operation. Given that the Knott Landfill has a
Leachate Collection and Removal System (LCRS) with greater slopes and design than
are typically required,3 it is likely that the LCRS should be able to handle the proposed
steam injection. However, some care will still need to be exercised in adding stream to
avoid leachate outbreak or slope stability issues that potentially can occur with typical
bioreactors. These risks are known in the industry and can be readily mitigated by
conscientious operation according to permit conditions.
• Risks – Potential risks to the proposed WTEG project appear to be relatively low from
an environmental and permitting aspect provided that WTEG assigns operational staff
experienced in landfill gas control and compliance and provides adequately designed
equipment to maintain air quality compliance as discussed in the environmental,
permitting, and operational sections of this TM. If the steam injection functions with
similar efficacy to a bioreactor, an environmental benefit of early stabilization of the
waste could be realized. However, HDR believes that the LFG production and financial
projections by WTEG may be optimistic, which raises the importance of the County
contractually protecting itself from risks, should the project fail to meet expectations.
This TM includes a section (See Contractual Risks in the last section) with detailed
comments and recommendation regarding an in-progress contact reviewed and
discussed by HDR and the County. We recommend that, in the case that the County
decides to implement the project, protections (possibly additional ones covering
subsequent negotiations) are included as the agreement is finalized in order to limit the
County’s risk and protect its financial interests. Given that this project is experimental
(the first of its kind proposed for full scale) and contains what HDR notes may represent
overly optimistic plans and assumptions by WTEG for the project; HDR recommends
that the risk should the project fail should be contractually solely borne by WTEG.
• Benefits to the County - This TM also discusses potential benefits of the project to the
County that would involve potential early stabilization of the landfill waste and payments
to the County for LFG produced for sale. Early stabilization of the waste, a stated goal
of the project, would be an environmental benefit mainly from reducing the time that the
waste would pose a threat to groundwater quality. The contract that the County is
negotiating with WTEG is assumed to provide royalty payments to the County.
In the development of this TM, HDR has relied on information provided by WTEG and the
County. We are assuming that the information is the most recent available as of the date of this
memorandum and that the information represents the best available information from WTEG
and the County. HDR has used our experience with landfill gas to energy projects as well as
general industry standards and information available from other sources as noted in this TM.
2 For basis of liquid requirements and additional discussion, refer to Liquid Sourcing in Landfill Gas Generation
section and Liquid Requirements in Overview Comparison to Non-Steam Bioreactors section. 3 Based on HDR discussions with Oregon DEQ (Joe Gingerich) and the County (Timm Schimke).
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 4 of 33
Background and Understanding
Deschutes County has been approached to consider the implementation of a WTEG proprietary
technology, which essentially consists of injecting steam into the KLF for the enhanced
production of landfill gas. HDR understands that WTEG’s project description includes the
following:
• A Piezo-Penetrometer Test (PPT) survey will be conducted by WTEG initially to
determine where to install gas collectors. Data from the survey will be used to create a
model of the waste to show what the characteristics of the waste are and where the gas
pockets are located and where perched leachate exists.
• A steam injection system including a landfill gas (LFG) collection system will be
engineered by WTEG based on the results of the PPT survey. LFG collection wells will
be installed. Steam injection points will be placed strategically to enhance the gas
production capabilities and collection wells will be installed to affect distribution of the
steam and collection of the LFG.
• WTEG will provide and use a Biogas Purification and Compression System
manufactured by Generon IGS, Inc., to process the raw LFG to product gas. Product
gas will be sold by WTEG to a buyer and injected into a natural gas pipeline adjacent to
the KLF facility.
• WTEG intends to enter into a binding agreement with the County to perform the project
as described. This TM includes HDR comments and recommendation on a draft
agreement that were discussed with the County during performance of this project.
In the development of this TM, HDR has relied on information provided by WTEG and the
County. We are assuming that the information is the most recent available as of the date of this
memorandum and that the information represents the best available information from WTEG
and the County. HDR has used our technical, regulatory, financial and contractual experience
with landfill gas to energy projects as well as general industry standards and information
available from other sources as noted in the report. Given that the basic concept of steam
injection into a landfill and some of the individual elements of the process and technology
proposed by WTEG is new and experimental, HDR could not compare WTEG’s proposed
technology and project based on information to other similar operating projects as we are not
aware of any others that exist.
This TM includes a review of the technical, permitting/regulatory, financial, and contractual
aspects of the Project, including an overview comparison to Non-Steam Bioreactors. Each
component of HDR’s review is included by section below.
Technical Review
HDR initiated the analysis by requesting that technical information from WTEG be provided. We
discussed the information provided to HDR with WTEG and requested and received follow-up
information to assist in our review. This included review of the following technical aspects of the
project (in general process flow order):
• Initial site profiling using the WTEG Piezo-Penetrometer Test (PPT)
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 5 of 33
• Landfill gas generation
• Landfill gas collection and control
• Landfill gas high-Btu processing and pipeline injection
PPT Testing
WTEG has proposed that the project begin with WTEG’s PPT testing procedure to develop a
three-dimensional profile of the waste mass for future use in detailed design and operation of
the steam injection process. According to WTEG, the PPT and also the Cone Penetrometer
Test (CPT) can be utilized to detect and profile internal gas pressures, perched liquids, vacuum
zones, dense soil layers, and other pertinent information.
HDR is familiar with the PPT and CPT equipment, but the use of the equipment to develop
three-dimensional models and interpretation to enhance steam injection are proprietary to
WTEG and their consultant, STI Engineering, Inc. As such, HDR cannot judge the efficacy of
STI’s proprietary interpretation of these results.
Based on the review of the information provided by WTEG, HDR’s opinion of the PPT Testing
process is that it should not be detrimental or cause harm to the KLF. The greatest risk is
penetration of the cell liner, but this can be mitigated similar to installation of conventional landfill
gas wells by allowing adequate separation to the liner using accurate as-built liner information
and recent survey elevations.
Landfill Gas Generation
WTEG has provided the following estimate of landfill gas generation for the proposed project
(from Executive Summary dated 2-7-13):
“WTEG will treat 4 acres of the landfill at a time and we will be converting 354 tons of organic waste per day
producing 2,549 mmBtu. Another 7 mmBtu will be produced naturally. Full the flow rate [sic] is controlled by
the amount of steam injected.”
This provides a basic landfill gas generation estimate by WTEG of 2,556 mmBtu/day from a 4-
acre parcel of the landfill undergoing the WTEG steam injection process. WTEG predicts a
minimum of 60% methane in the landfill gas generated by this method. Conversion using the
nominal heating value of methane at approximately 1,000 Btu/cubic foot yields an estimated raw
landfill gas flow rate of 2,958 cubic feet per minute (cfm) at 60% methane 4.
WTEG justifies this predicted generation rate as follows:
“The Steam Injection Process is designed based on the amount of waste currently in place and the amount
of refuse that is imported per day. We may assume that a total for both cells is 4,456,000 tons in place
based on the data provided. It is also assumed that 50% of the refuse is organic material or 2,228,000 tons.
Since the annual rainfall is only 8 inches it is assumed that 3 tons per acre per day was converted into
landfill gas (LFG) for the half-life of the landfill or 875,675 organic tons.
4 2,556 mmBtu/day * 1,000,000 Btu/mmBtu * 1 cubic foot/600 Btu * 1 day/1,440 minutes = 2,958 cubic feet per
minute
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 6 of 33
The landfill imports 315 tons of refuse per day. It is typically assumed that 50% of the refuse is organic or
158 tons.
If 5 acres are treated at a time and convert 450 – 158 tons of import = 292 organic tons to LFG then the gas
field will last 8.5 years. It requires about 56 gallons converted to steam per ton or 25,000 gallons per 5 acres
per day. With 5 acres treated, 200 barrels of crude can be produced per day.”
Modeling and Estimation
The WTEG calculation methodology outlined in the paragraphs above is unconventional and
HDR is not able to agree on the assumptions made in WTEG’s calculations. It is generally
unclear to HDR how the historical waste in place is taken into account. In addition, HDR’s
independent analysis and information received from the County arrives at differing values for
waste in place, waste receipt volumes, and organic content. Rather than debate individual
values and methodology, Figure 1 provides a comparison of the WTEG estimated landfill gas
generation rate in comparison with a spectrum of generation models. This spectrum provides
independent estimates of landfill gas generation from conventional landfill operation to ideal
laboratory conditions (maximum theoretical gas generation).
HDR utilized the EPA LandGEM landfill gas emissions model version 3.02 to estimate the LFG
generation rates. The model was manually adjusted to have waste capacity comparable to
WTEG’s planned 4-acre tracts. The model LFG generation variables (k and Lo) were also
manually adjusted to create five “scenarios” providing a spectrum of LFG generation rates.
Scenarios 1, 2, and 3 are utilize variables to model “field” LFG generation rates for dry tomb and
bioreactor conditions. Scenarios 4 and 5 utilize variables to model “laboratory” LFG generation
rates that have not been replicated in the field. The calculated assumptions and EPA LandGEM
models for each scenario are included in Attachment A. The following should be considered
when reviewing this Figure:
• Waste values and characterization are per County provided information
• The waste volumes have been manually adjusted to model a 4-acre by 100-foot deep
“cube” of waste for comparison with WTEG planned methodology for a roving 4-acre
tract. This results in a conservatively high assumption of waste design capacity at
609,840 tons.
• Flow rate shown is for landfill gas with 60% methane (for comparison to WTEG claim)
Figure 1 illustrates that WTEG predicts (Proposed) that their steam injection process will
effectively increase landfill gas generation rates to greater than double the published rates
typical of bioreactor landfills in the industry (Scenarios 2 and 3) and up to 90% of the theoretical
maximum potential predicted by laboratory-derived thermodynamic properties of the waste
materials (Scenario 5).
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 7 of 33
Figure 1 – Proposed LFG Generation Curves
Miramar Pilot Study Comparison
HDR understands that the basis for these claims is derived from the 10-month pilot study
performed at the Miramar Landfill in 2005-2006. From WTEG text:
“In 2005 and 2006 STI Engineering performed a 10 month long Steam Injection Pilot Study at the Miramar
Landfill in San Diego, California. Two acres were selected for the study, one as a control with no steam
injected and one with steam injection. This test acre was instrumented with 12 thermocouples and 2 static
piezometers to monitor the effects of the steam migration through the landfill as well as settlement
monuments.
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
4,500
L
F
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Proposed LFG Generation from 4-Acre Tract at KLF
LFG Generation Spectrum
Scenario 1 -Typical AP-42 parameters K (methane degradation rate) & Lo (methane generation potential). No recirculation of liquids.
Scenario 2 -Recirculation of liquids. Published field bioreactor parameters K and Lo
Scenario 3 -Recirculation of liquids. Maximum field bioreactor LandGEM values for parameters K and Lo
Scenario 4 -Maximum lab values for parameters K and Lo. Optimum lab conditions for site-specific KLF waste.
Scenario 5 -Absolute maximum values of Scenarios 1 through 4 for parameters K and Lo. Optimum lab conditions for generic MSW.
Proposed -Proposed value of 2,958 scfm based on WTEG estimate of 2,556 mmBtu/day at 60% methane.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 8 of 33
With steam injection the gas production was increased by 5.7 times. If 5,000 gallons per day were used
instead of just 1,500 gals, then the gas production would have been increased 27 times.”
To compare the results of this pilot study, Figure 2 shows a similar landfill generation spectrum
for a 1-acre by 50-foot deep cube of waste to emulate the Miramar Pilot Study. HDR again
utilized the LandGEM model to estimate the LFG generation rates. The model was manually
adjusted to have waste capacity comparable to Miramar Pilot Study 1-acre by 50’ deep tract.
The model LFG generation variables (k and Lo) were also manually adjusted to create five
“scenarios” providing a spectrum of LFG generation rates. Scenarios 1, 2, and 3 are utilize
variables to model “field” LFG generation rates for dry tomb and bioreactor conditions.
Scenarios 4 and 5 utilize variables to model “laboratory” LFG generation rates that have not
been replicated in the field. The calculated assumptions and EPA LandGEM models for each
scenario are included in Attachment B
Figure 2 – Miramar Pilot Study LFG Generation Curves
0
500
1,000
1,500
2,000
2,500
LF
G
G
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)
Year
Miramar Pilot Study LFG Generation from 1-Acre Tract
LFG Generation Spectrum
Scenario 1 -Typical AP -42 parameters K (methane degradation rate) & Lo (methane generation potential). No recirculation of liquids.
Scenario 2 -Recirculation of liquids. Published field bioreactor parameters K and Lo
Scenario 3 -Recirculation of liquids. Maximum field bioreactor LandGEM values for parameters K and Lo
Scenario 4 -Maximum lab values for parameters K and Lo. Optimum lab conditions for site-specific KLF waste.
Scenario 5 -Absolute maximum values of Scenarios 1 through 4 for parameters K and Lo. Optimum lab conditions for generic MSW.
Observed -Observed flow of 228 scfm at Miramar Pilot Study reported by WTEG after adding 1,500 gal/day steam injection.
Claimed -Claimed possible flow of 1,080 scfm at Miramar Pilot Study. Theoretical addition of 5,000 gal/day steam injection. Not actually realized.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 9 of 33
The Figure illustrates that the actually observed landfill gas generation rate at Miramar with the
available leachate (Observed line) used in the steam injection process matches the maximum
rate modeled using published industry field bioreactor data (Scenario 2). However, the claimed
landfill gas generation rate (Claimed line - not proven or achieved in the pilot study) theorized by
WTEG if more liquids were available would again fall in the spectrum of laboratory only
conditions.
Steam Injection Process
In order to achieve the estimated landfill gas generation rates advertised, WTEG intends to
employ the injection of steam in a proprietary process. This process is described in detail in the
provided documents and generally consists of injection of steam in the middle of each one-acre
tract with four landfill gas collectors at each corner of the square tract providing vacuum to move
the steam laterally through the waste mass.
In general, HDR views this as a process wherein the general goal is to increase the availability
of moisture to the methanogenic bacteria in the waste mass to enhance their decomposition
activity on the organic matter and subsequently increase landfill gas production. That the
methanogenic bacteria require moisture and ideal conditions for decomposition activity
(biostabilization of waste) is well known.
The waste stabilization bacteria primarily operate in three different groups 5:
1. One set of bacteria is responsible for hydrolyzing organic polymers and lipids to basic
structural building blocks such as amino acids;
2. A second set of bacteria called “acidogens” is responsible for fermenting the breakdown
products (such as amino acids) to simple organic acids; and
3. A third set of bacteria called “methanogens” are responsible for converting the acids into
methane and carbon dioxide.
Therefore, the methanogens – a type of mesophilic bacteria – plays the final and most critical
role in methane generation. The optimum temperature range for mesophilic bacteria is
generally reported as 80o to 120o Fahrenheit, with limits for landfill gas well temperatures in
regulated landfills restricted to less than 131o Fahrenheit. Steam injection, at greater than 212o
Fahrenheit may provide an inhospitable environment for the methanogenic bacteria – although it
is conceded that this temperature is restricted to the few feet directly adjacent to the steam
injectors. Since this is the case, it is assumed that the process serves to move water vapor in
ever-decreasing temperature (and thus moisture loading) laterally through the waste mass.
Therefore, HDR views the steam injection process as a variation of pressurized moisture
addition into the waste – with a risk of impacting methanogen growth near the injection point
with excess temperatures.
5 Summarized from: Integrated Solid Waste Management: Engineering Principles and Management Issues;
Tchobanoglous, George, Hilary Theisen, Samuel Vigil; Irwin/McGraw-Hill; 1993.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 10 of 33
The concept of pressurized moisture addition is not a new practice in the solid waste industry.
The WTEG proposed steam injection closely resembles these projects but with the added
technical and financial burden of heating the liquid to make steam and the aforementioned
temperature risk to methanogenic bacteria. The quantitative advantages that steam injection
are purported to provide (versus liquid injection) are not fully proven in field testing. It is
assumed that the decrease in temperature will cause the steam to condense into a liquid water
state at some point between the steam injector and the collection wells. At that temperature
point, the remaining water vapor may be influenced by the vacuum exerted by the gas collection
wells, but the liquid water will be governed by liquid properties of movement within the waste
mass. HDR is not aware of information that verifies that the injected steam will travel the
distance (greater than 100 linear feet) from the injection points to the collection wells prior to
condensing.
As stated in the previous section, WTEG’s predicted outcomes for KLF are based on the
Miramar 1-acre pilot project. Notice in Figure 2 that after steam injection, the reported results
(Observed line) came close to the landfill gas generation modeled by LandGEM utilizing
published bioreactor data (Scenario 2). This indicates that the steam injection did distribute
moisture effectively and pushed the landfill condition towards a bioreactor system – an expected
phenomenon. However, the claim that landfill gas generation could have been 27-times greater
than the pre-study flow rate (Claimed line) if the added water was 5,000 gallons per day was not
proven. The observed data would suggest that the steam injection did increase the moisture
content, and that the waste mass may have already reached an optimum condition with the
1,500 gallons/day addition – a possibility endorsed by the reported flow rate being consistent
with a LandGEM modeled bioreactor system (Scenario 2).
Waste has certain inherent methane generation potential or energy content (see Lo calculations
in Attachments A and B). This potential will not increase regardless of how much moisture is
added into the waste mass. It is expected that moisture delivery is the key to optimization of the
waste’s landfill gas generation potential; however, WTEG’s maximum claims have not been
supported by published field data, and may not be valid if a waste mass has already reached
optimum moisture conditions.
Liquid Sourcing
As discussed in previous sections, WTEG proposes optimization of landfill gas generation by
means of steam injection. This is similar in concept to a bioreactor operation. Specific to the
KLF project, WTEG proposes an optimal liquid requirement of approximately 5,000
gallons/acre/day6. The issue of note for the proposed WTEG project at the KLF has to do with
the sourcing of this quantity of liquid. KLF currently has approximately 38 acres of lined cells
6 Liquid quantity based on information provided in WTEG proposal dated February 7, 2013, “Executive
Summary – Green Environmental Solutions for the Deschutes County Landfill Stabilization Projects”,
page 6: “It requires about 56 gallons converted to steam per ton or 25,000 gallons per 5 acres per day.”
Statement is consistent with WTEG stated liquid requirements at Miramar Pilot Study at 5,000
gallons/acre/day.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 11 of 33
which generate a normalized annual average of 287,000 gallons/month (9,500 gallons/day)7.
This quantity is short of the required amount of 20,000 gallons/day for a 4-acre tract by 10,500
gallons per day. A magnitude of 10,500 gallons per day would equate to a residential usage
rate for approximately 26 homes 8.
This issue was also encountered at the Miramar pilot study. The one acre pilot study required
5,000 gallons/day, but City of San Diego staff report that the entire Miramar site produces only
approximately 15,000 gallons/month (500 gallons/day) in winter and 200,000 gallons/month
(6,667 gallons/day) of leachate in summer. The Miramar larger lined area was unable to
support the liquid needs of a smaller pilot study.
Landfill Gas Generation Conclusions
In summary, this section provides perspective as to how the WTEG proposed landfill gas
generation projections compare to the generally recognized spectrum of landfill gas modeling
using a variety of published field and laboratory variables. The modeling efforts have been
adjusted to provide a range of comparison.
In each case, WTEG’s projected landfill gas generation estimates greatly exceed those
published from actual field data, and fall into the realm of laboratory and theoretical output. It is
known that waste has certain inherent methane generation potential or energy content (based
on the available organic substrate for methanogenic bacteria). This potential will have a limit
regardless of how much moisture is added into the waste mass. Therefore, the increase in
liquid/steam injection will not necessarily result in a commensurate increase in LFG generation.
The ability to distribute the moisture effectively within the organic waste mass will have the
greatest effect. This is understood as WTEG’s goal with the steam injection process. However,
due to liquid sourcing constraints, WTEG was able to match published peak bioreactor gas
generation levels, but was unable to prove higher gas generation rates in the Miramar field pilot
study.
Based on the documents provided, it seems that the WTEG projected KLF landfill gas
generation rates are estimated largely on the basis of WTEG theorized Miramar generation
rates that were not actually achieved. In the absence of actual field or laboratory data from
steam injection to the contrary HDR can only speculate an opinion that the generation rates
from the proposed steam injection would fall somewhere between the bioreactor curves for the
published and maximum field based LandGEM values shown by Scenarios 2 and 3 9.
Based on the review of the information provided by WTEG, HDR’s opinion is that gas
generation at the KLF will not match the estimated quantities proposed by WTEG. However,
the steam injection and collection process should not be detrimental or cause harm to the KLF
7 Based on County-provided leachate data for 2012.
8 Based on an assumed 400 gallons per day for a typical household family of four; source:
http://www.epa.gov/WaterSense/pubs/indoor.html
9 Attachment A provides detailed description of Scenario LandGEM models for KLF. Attachment B provides
detailed description of Scenario LandGEM models for Miramar Pilot Study.
WTEG Technical Review
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Page 12 of 33
provided that the leachate collection system is installed and operated conscientiously by the
County. The greatest technical risk is penetration of the cell liner, but this can be mitigated
similar to installation of conventional landfill gas wells by staying a conservative distance from
the landfill liner by means of accurate as-built information and recent survey elevations. WTEG
has indicated that it understands this risk and has stated that the intent is to stay well above
landfill liner elevations.
Landfill Gas Collection and Control
WTEG proposes to operate steam injection and landfill gas collection operations on roving 4-
acre tracts on the lined area of KLF. It is important to note that WTEG does not propose
expanding the County’s existing gas collection system to all areas of the landfill, and does not
propose operating a gas collection system that would comply with any future regulatory
requirement for KLF to provide collection coverage for their landfill (if this is required in the
future). This is discussed in more detail in the Permitting section of this memorandum.
Collection System Efficiency
WTEG proposes to collect landfill gas from roving 4-acre tracts at the KLF in conjunction with
steam injection. WTEG has not distinguished between landfill gas generation and landfill gas
collection estimates for the KLF project. WTEG has stated to HDR that it expects that 99% of
generated gas will be collected. It is assumed that WTEG takes this position due to the small
scale of the project (4-acre tracts). However, it must be noted that industry standard gas
collection efficiency for landfills without final cover in place is approximately 75%. HDR is of the
opinion that WTEG may not achieve 99% collection efficiency. This discrepancy may serve to
decrease the expected LFG collection by up to 25%. This is discussed in more detail in the
financial section of this memorandum.
Flaring Capacity
The County has indicated to HDR that WTEG has stated that they will provide a backup flare for
the Knott Landfill. However, the information provided to HDR by WTEG does not appear to
provide for the installation of a backup flare station with capacity to destroy the collected gas.
This is contrary to industry standard practice, and preliminary discussions with regulators (see
Permitting Section) suggested that they would require this flare capacity. This is important since
the steam injection process will cause the increased generation of landfill gas. Projected
availability (up-time) of any processing facility is approximately 92% to 95% annually (in best-
case operation), which does not equate to industry and regulatory backup requirements. Due to
recent odor issues10 with neighbors at the KLF site, the lack of a back -up flare to handle the
combustion of gas during processing down times appears problematic. The addition of a flare
station with capacity for WTEG-estimated LFG flow rates would add approximately $500,000 to
the initial capital cost of the project.
10 Based on discussions with the County and Oregon DEQ.
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Landfill Gas Collection and Control Conclusions
Although the previous section disagreed with the magnitude of WTEG estimates of landfill gas
generation at KLF, it is agreed that the steam injection process could increase landfill gas
production. As such, this increased gas production must be collected and controlled to prevent
odor and other issues (migration). The County should consider its goals from an agreement
with WTEG. Specifically, the following issues:
• The proposed project does not provide the County with a working gas collection system
after WTEG leaves each 4-acre tract. The County will be relying upon WTEG’s
assertion that “all” gas has been extracted from each 4-acre tract. However, there
remains the possibility that once WTEG leaves an area, fugitive gas emissions could be
higher than prior to the project (due to the effects of the steam injection). The County
should consider how this gas will be collected and controlled.
• The proposed project does not provide for increasing flaring capacity at the site to
handle the increased gas production. General industry practice includes a backup
control device with sufficient capacity to handle all LFG collected.
• Discussion with regulatory agencies (see Permitting Section) have left open the
possibility of triggering enhanced surface monitoring (at a minimum) and/or adjustment
of New Source Performance Standards (NSPS) Tier 2 reporting.
• The County may want to compile or establish baseline compliance data (perimeter probe
date, surface emissions, landfill gas collection, etc.) and tie this baseline into the
proposed agreement such that quantifiable increases can trigger specific action or
resolution by WTEG.
Landfill Gas Processing and Pipeline Injection
WTEG proposes to process the collected LFG into a high-Btu product gas for sale to a buyer by
means of injection into the local Pacific Gas Transmission pipeline that is stated to run adjacent
to the KLF. This is a feasible use of the gas, assuming that WTEG can collect the flow rates
proposed (discussed in detail previously) and the proposed pipeline is able to accept the
product gas. As a general rule, financial feasibility decreases drastically with decreasing flow
rates, as historically, high-Btu processing has been feasible for larger landfills with projected
LFG flow rates in excess of 2,500 cfm. However, these technologies have been making
advances in recent years to achieve financial feasibility for landfills with ever-lower flow rates.
The product gas, which is approximately 99 percent methane (and will have various restrictions
on other contaminants), can be injected into existing natural gas pipelines as proposed by
WTEG. Processing the LFG to this high Btu product requires complex processes – e.g.,
membrane filtration, pressure swing adsorption, or amine scrubbing.
Technical
WTEG proposes a turnkey-style containerized processing facility provided by Generon IGS.
The proposed process will operate on the principle of pressure swing adsorption to separate
carbon dioxide (and some other constituents) from the landfill gas. This unit also has the ability
to remove hydrogen sulfide with packed media beds. These are generally industry-standard
WTEG Technical Review
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Page 14 of 33
processes that are successful in removing these compounds. The technology is filtering down
in recent years to package units of this type. Based on the vendor specification provided by
WTEG the proposed facility is sized for 3,000 cfm at 60% methane feed gas. WTEG’s sales
contract with the ultimate buyer of the product gas will govern if more processing is needed for
other constituents.
Operational
WTEG’s proposal calls for WTEG to be solely responsible for operation of the 4-acre gas
collection tracts and the processing of the gas with the Generon unit. However, the following
are important considerations that should be taken into account. These may have impacts on
County revenue or operations.
• Flaring capacity should be installed for full gas flow (as discussed in the previous
section), since the Generon unit or pipeline injection point could be shut down
unexpectedly.
• An important operational issue for high-Btu processing is that these units do not easily
remove oxygen. The receiving pipelines impose a strict limit on the oxygen content of
the injected gas. As a result, WTEG might only be able to accept and utilize “rich”
landfill gas and might not be able to accept landfill gas collected from any existing county
collection systems or systems pulling gas for odor or migration control. These “extra”
sources could contain too much oxygen. This criterion must be controlled from the
collection system and may preclude WTEG accepting gas from (some) County
extraction wells.
Overview Comparison to Non-Steam Bioreactors
Based in part on the technical analysis in Task 1, HDR reviewed WTEG’s assumptions and
compared the performance expectations to those of other liquids recirculation/injection landfills.
Although HDR recognizes that WTEG asserts a patented technology, HDR views this process
as a variant of a bioreactor process, wherein the general goal is to increase the availability of
moisture to the methanogenic bacteria in the waste mass to enhance their decomposition
activity on the available organic matter and subsequently increase landfill gas production. That
the methanogenic bacteria require moisture and ideal conditions for decomposition activity
(biostabilization of waste) is not disputed.
Landfill Gas Generation
HDR asserts that the baseline of comparing their expected performance to the published data of
other liquids recirculation processes (non-steam recirculation or bioreactor) to be an appropriate
comparison. As such Figure A and Figure B (and related discussion) in the previous Technical
Review section compare landfill gas generation rates across this spectrum.
WTEG Technical Review
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Liquid Requirements
Specific to the KLF project, WTEG proposes an optimal liquid requirement of approximately
5,000 gallons/acre/day. Although not clear on the conversion of this value, WTEG states that
this is based on a factor of 56 gallons/ton of waste. 56 gallons/ton of waste is a quantity of
liquid that is generally consistent with published data. For example, the volume of liquid
required for waste with an initial moisture content of 25% to achieve a target moisture content of
40% is approximately 60 gallons/ton of waste 11. However, the challenge is creating conditions
for uniform distribution of the added liquids so that the moisture can be utilized in the
biodegradation of the waste. This is the aspect that WTEG proposes to address with steam
injection.
Enhanced Waste Stabilization
One of the advantages of bioreactor landfills and the proposed steam injection process is the
potential for earlier stabilization of the waste mass. This is a stated goal of the project 12 and a
typical goal of landfill bioreactor projects as earlier stabilization of waste is an environmental
benefit of bioreactors and the proposed steam injection project compared to “dry tomb” landfills,
where the addition of outside moisture is not practiced. Bioreactor research has shown that
municipal solid waste can be more rapidly degraded and made less hazardous in a shorter
period 13. This provides a potential decrease in long-term environmental costs and risks. The
leachate quality in a bioreactor landfill more rapidly improves, which reduces the period that the
landfill poses a threat to groundwater quality. The WTEG proposed process for the Knott
Landfill will likely have this benefit similar to bioreactor landfills.
Operations
Similar to a conventional bioreactor, the WTEG process will be injecting steam (liquid) into the
waste mass. As such, the possibility for overloading of the leachate collection system and/or
slope stability and side-slope leachate outbreaks increases. WTEG has reported that the steam
injection process will use less liquid than a typical bioreactor, this reducing or removing this
concern. However, the WTEG reported KLF liquid requirements are similar to bioreactor
operation. Therefore, WTEG’s process would seem to carry the same risk as conventional
bioreactor operation in these respects. These risks are known in the industry and can be
mitigated by conscientious operation according to permit conditions.
Permitting/Regulatory Review
HDR reviewed the permitting/regulatory aspects of the project, including:
• Allowable recirculation of liquid/steam on lined or unlined areas of Knott Landfill.
• Allowable use of leachate to generate steam at landfill.
11 Source: Townsend, T., Kumar, D. Ko, J. Bioreactor Landfill Operation: A Guide for Development,
Implementation and Monitoring: Version 1.0 (July 1, 2008). 12 Draft DEQ RD&D Permit Application letter document file (letter date 3/27/12) provided by the County to HDR. 13 USEPA website, Waste-Non-hazardous Waste Municipal Solid Waste;
http://www.epa.gov/osw/nonhaz/municipal/landfill/bioreactors.htm.
WTEG Technical Review
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• Limitations of operational permit requirements.
• Future New Source Performance Standards (NSPS) and Title V requirements for landfill
gas collection and how WTEG process would have to fulfill these during the contract
period.
• General – identify potential permitting hurdles or fatal flaws.
• Discussions with regulators regarding permitting issues and the viability of the project
related to the bulleted items above.
Regulation and Project Permitting Background
Major Applicable Regulations
Solid waste permitting and compliance of landfills in Oregon are governed under Oregon
Administrative Rules (OAR) enforced by the Department of Environmental Quality (DEQ) under
solid waste provisions contained in 340-93. Oregon is an approved state under Federal rules
contained in 40 Code of Federal Regulations (CFR) Part 258. This means that the DEQ
enforces landfill regulations under OAR 340-93 that meeting minimum standards in 40 CFR Part
258. The 40 CFR Part 258 allows Oregon as an approved state to issue research,
development, and demonstration (RD&D) permits. This rule allows the Director of Oregon
Department of Environmental Quality (DEQ) to issue permits waiving specific requirements of
the MSWLF criteria in order to promote innovative and new landfill technologies and operating
processes, provided that landfill operators demonstrate there will be no increased risk to human
health and the environment.
During compilation of this TM, HDR contacted Joe Gingerich of DEQ, who would be responsible
for solid waste permitting under the main solid waste permit (Title V would be under DEQ, Mark
Fisher). Mr. Gingerich indicated that DEQ would take the lead on permitting the project under
the DEQ Guidance for obtaining a DEQ RD&D permit (June 8, 2012). Based on other
information provided by Mr. Gingerich we understand that the August 24, 2012 certification letter
from DEQ to the USEPA states that the draft RD&D rules were intended to be effective of that
date. Further emails provided to HDR by DEQ indicate that the final process for adoption
including a noticing and public review process will involve that after the Federal Register (FR)
review notice is reviewed by USEPA attorneys (in progress December 12, 2012) there will be a
30 day public comment period and become effective 60 days after the (FR) review assuming no
adverse comments.
Major Permits Related to the Proposed Project
The Knott Landfill DEQ permit is Number 6, which was issued on August 10, 2001, lists an
expiration date of September 1, 2010. However, HDR understands that this permit is in the
process of being reviewed and renewed by DEQ. This permit covers most aspects of design,
operations and environmental compliance. In addition to the solid waste permit issued by DEQ
the Knott Landfill also has a Title V permit No. 09-0040-TV-01 (expiration 8/1/2016) that governs
compliance with air quality and emissions that would be related to the proposed project for
WTEG Technical Review
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Page 17 of 33
steam injection of the landfill. Based on information provided by WTEG we also understand that
a Land Use Permit (LUP) is issued to the landfill from the County. Under the proposed project
the LUP would need to be updated based on required permit and approvals conditions by DEQ
and any additional requirements that the County would wish to require.
HDR reviewed in cursory level selected information provided by WTEG or the County regarding
the proposed project that included draft permit documents in various state of progress. These
included a draft DEQ RD&D Permit Application 14, the DEQ permit, the Title V permit, and a draft
notice of intent to construct the proposed project intended for DEQ review under the Title V
permit.
Discussion of Permitting Issues
The discussion of permitting issues which follows begins with discussions with regulators
regarding the proposed project and then includes their or HDR interpretation of the viability of
the proposed project and how the project might be expected to be controlled by permitting
requirements. This is followed by discussion of the particular regulatory issues listed at the top
of this major section.
Regulatory Input to HDR regarding the proposal project
Solid Waste Permit under DEQ 340-93
Based on a telephone conversation with Mr. Joe Gingerich and HDR (Attachment C), Mr.
Gingerich provided the following information and opinions:
• The unlined phases of the project he would expect would be difficult if not impossible
to permit under RD&D. RD&D would cover recirculation and potentially injection into
lined landfill, only.
• Oregon is an “approved” state under Federal regulations and can issue permits
under RD&D. Mr. Gingerich indicated there might be only be limited USEPA
involvement he thought that DEQ has authority to issue RD&D permit without
USEPA oversight.
• Mr. Gingerich indicated that from what he is familiar with about this project to date it
sounds like it may be a good idea if it makes the landfill decompose and become
less of a threat to environment sooner, as long is it protects the environment
according to permits.
• Mr. Gingerich indicated that he would be the staff overseeing the general solid waste
permit. Increased emission and controls would be permitted under the DEQ Title V
permit process, overseen by Mark Fisher (of the Bend, OR DEQ office).
• Mr. Gingerich he envisions the process as an “iterative” process where the project
would start small and then if demonstrated successful could be continued.
14 Microsoft Word document with March 27, 2012 date.
WTEG Technical Review
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• Mr. Gingerich noted that neighbors of the landfill have expressed concern about
potential health impacts. He noted that air emissions compliance aspects would
have to be addressed.
• Mr. Gingerich indicated he is comfortable about doing a project such as this at the
Knott Landfill because it is well designed. It has “overkill” in a liner drainage system
with large rock and drainage net and good LCRS and liner slopes. He would expect
very little hydraulic head on the liner, in compliance with regulations.
• Mr. Gingerich indicated that the permit renewal for this site (needed for approval of
permit changes such as this proposed project) has been in the process for a while
and his thinking may be to wait until the proposed WTEG project would get bundled
in to process the renewal. He said that it would be possible to hold one hearing for
the permit renewal covering both air quality and solid waste issues. He indicated
that timing to write the permit may be 60 to 90 days but if the project were
controversial via the public hearing it is hard to gauge the timing.
Air Quality Permitting under Current Title V Permit
HDR spoke with Mark Fisher of the Oregon DEQ about the proposed WTEG project, specifically
focused on the steam injection and the emissions units anticipated by WTEG. Attachment D
provides a written log of the conversation, and a summary of the feedback and discussions is
provided below:
• Mr. Fisher stated that there have been recent odor complaints from KLF neighbors.
He attributes this to the inability of the site to collect all of the LFG being generated
because the existing flare capacity is too small. He also stated that the landfill is a
pro-active permittee and that no enforcement actions have been taken for this odor
complaint.
• Mr. Fisher agreed that the RD&D application will be the preferred permitting
mechanism. He stated that all RD&D permitting is handled from the Solid Waste
Group (Joe Gingerich), but that certain conditions might be introduced from the air
group (mentioned additional surface emission monitoring requirement possible).
• Mr. Fisher stated that the preferred method for permitting these activities through the
air group is by means of a Notice of Intent to Construct (Form ND-901). This should
be completed in conjunction with RD&D application. Title V permit would not be
modified until the next renewal cycle. The Notice of Intent to Construct would be
reviewed by DEQ against established emission limits for the site (as set by the
existing Title V permit).
• An important issue/question is whether the enhanced generation of LFG in
controllable areas of the landfill (4-acre tracts) might affect the New Source
Performance Standard (NSPS) 50 Mg/yr non-methane organic compound (NMOC)
limit for the entire landfill. Specifically, this could then affect the requirement for
WTEG Technical Review
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Page 19 of 33
installation of a GCCS on the entire landfill (as governed by the Tier 1 and Tier 2
reporting).
Mr. Fisher stated that, at a minimum, the existing NSPS Tier 2 Report would require
modification or the new Tier 2 Report (due in 2013) would need to take LFG samples
from the steam injection areas. Discussion was not conclusive on how the NMOC value
would affect the Tier 2 Report or if additional modifications to the report would be
required based on the proposed LFG generation rates in these areas. The Tier 2 Report
relies on NMOC concentration in the LFG (unclear how this will be affected by steam
injection) and the estimated quantity of LFG to estimate a yearly NMOC emission rates.
The Tier 2 report also governs the requirement for a landfill to install a LFG collection
and control system (on the whole landfill).
• An important issue/question regards the RD&D permit application (WTEG draft) that
proposes surface emission monitoring in initial stages. This is another aspect of LFG
operations that is customarily governed for the entire landfill by the NSPS Tier 1 and Tier
2 reporting.
Mr. Fisher stated that, at a minimum, DEQ would likely require surface emission
monitoring on the current 4-acre steam injection area as well as the previous 4-acres as
WTEG moves its process across the landfill. This would likely be a condition of
approval.
• Mr. Fisher stated that the de-minimis carbon dioxide emissions are 2,766 tons/year at
this site. If WTEG would like to install a processing unit that emits carbon dioxide (the
Generon unit as proposed), the emission rate may be an issue that would require review
by DEQ.
• Mr. Fisher clearly stated that upgrade of a flare system would be required to have
capacity for all collected LFG (even if flare is only used as backup). This would need to
be addressed in the Notice of Intent to Construct and would likely be a condition of DEQ
approval.
Allowable recirculation of liquid/steam on lined or unlined areas of Knott Landfill
Based on the above input from DEQ it appears that the DEQ does not see fatal flaws with the
project from a regulatory perspective provided that the project meets all particular regulations
that will include adequate recovery of leachate to minimize the head on the liner in compliance
with regulations and control of air emissions in compliance with regulations. Mr. Gingerich
believes that if the project also meets intended goals of decomposing the landfill sooner it would
be beneficial. Further he feels that the Knott Landfill would be a good site to attempt an RD&D
project as proposed because the liner system is more robust than required by regulations and
has “good” liner slopes which should minimize the head on the liner system.
WTEG Technical Review
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Page 20 of 33
HDR notes that bioreactor landfills have been successfully implemented throughout the US and
have been able to control the head on the liner to meeting CFR Part 258 and state regulations
adequately. Given that WTEG asserts in concept that its steam injection project will inject much
less water than a typical bioreactor it appears feasible that the proposed project would be able
to meeting regulations and not introduce significant additional threat to groundwater from liner
leakage.
Landfill liner temperatures have been studied for years and more recently for bioreactors, as
liner temperatures up to 50 degrees C (122 degrees F) in the laboratory show only negligible
degradation effects. This has not been an issue to date with bioreactors that HDR is aware of.
For example, maximum temperatures on the landfill liner in the Yolo County full scale bioreactor
were a maximum of 34 degrees C (93 degrees F)15 and bioreactors generally produce
temperatures below concern for liners. We would expect that the proposed project liner
temperatures would be similar to a full scale bioreactor as WTEG indicates that steam injection
would not be extended to deeper portions of the landfill. Because steam injection has not been
performed and related to liner temperatures this is an unknown but we believe the probability of
the liner temperature being much different than a full scale bioreactor and an area of concern is
low and should therefore also not be a regulatory concern.
Allowable use of leachate to generate steam injection at the landfill
The 40 CFR part 258 regulations allow recirculation of leachate to a liner landfill which
recirculation to the originating cells. The RD&D regulations also allow recirculation of leachate
as well as outside liquids into lined landfills, and in that sense are less restrictive, provided that
the RD&D applicant shows than the environment will be protected commensurate with the 40
CFR part 258 regulations. This should allow WTEG to use leachate to generate steam for the
proposed project. In addition, there are allowances in the regulations to allow the recirculation
of LFG condensate into the landfill; therefore, it is probable that regulators would also allow the
use of LFG to generate steam for recirculation if desired by WTEG.
We understand that WTEG intends to create and inject the steam in a closed system thereby
eliminating emissions from steam into the atmosphere, and eliminating atmospheric intrusion
and the injection of air into the waste mass. This should allow permitting by DEQ. The DEQ
may require contingency plans (by WTEG as the applicant) be provided with the permit
application in case there would be any unforeseen above grade ruptures or failures of the
system as steam produced from leachate could produce a release that poses a potential threat
to the environment and/or exceeds permit requirements for the solid waste or air quality permit,
or both. Similarly, contingency plans or monitoring procedures may be required to ensure that
the system remains closed to atmospheric intrusion, as injection of air into the waste mass
could contribute to subsurface combustion/oxidation if not promptly discovered.
15 Data from January 2001 to June 2003; based on email Ramin Yazdani, Yolo County, November 24, 2004.
WTEG Technical Review
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Future New Source Performance Standards (NSPS) and Title V requirements, Federal NSPS
regulations (40 CFR Subpart WWW) are applicable for landfills with a design capacity greater
than or equal to 2.5 million megagrams (Mg) and 2.5 million cubic meters. The KLF exceeds
the capacity threshold for applicability of the NSPS regulations and has been reporting
estimated emissions of NMOCs. In the past, the County has chosen to determine the site-
specific NMOC value at the KLF by performing Tier 2 sampling and analysis as specified in 40
CFR 60.754(a)(2)(ii). The requirement for collection and control of all LFG generated at a site is
governed by the results of this report. If the Tier 2 calculations show estimated NMOC
emissions below 50 Mg/year, then a LFG collection and control system is not required by NSPS.
In 2009, the County submitted a Tier 2 report to the DEQ with an average site-specific NMOC
content of 729 ppmv (as hexane) and calculated a peak NMOC emission rate of 45.6 Mg/yr in
2012 (based on assumed future waste receipt estimates). An updated Tier 2 report is required
to be submitted by October 27, 2013. As stated above, DEQ will require (at a minimum) some
LFG sampling in the WTEG steam injection areas. It is unclear if this will increase the site-
specific NMOC concentration average.
HDR has performed a desktop LandGEM model using the same site-specific rate (729 ppmv)
and adjusted future waste receipt based on current estimates. In HDR’s calculation, the KLF
site might exceed the 50 Mg/yr NMOC threshold by 2023. This later date is due to the drop-off
in waste receipt tonnages in recent years (and estimated growth rate). This result is highly
contingent on gas sampling and future waste receipts, however, the County should consider the
implications of this “unofficial” result since it points to the possible requirement of LFG collection
and control over the entire KLF within the contract period with WTEG. Previous sections have
already outlined the fact that WTEG will not be providing the County with a permanent collection
system that would meet this potential requirement.
The County should also be aware that this assumes that the requirement for LFG collection and
control will continue to be governed by the NSPS Tier 2 reporting. It is within DEQ’s purview to
accelerate the LFG collection and control requirements for the whole site based on the
proposed LFG generation rates expected by WTEG. Discussions with Mr. Fisher at DEQ were
non-committal in regard to this.
Limitations of operational permit requirements
Based on discussions with DEQ staff it appears that the DEQ would intend to permit the project
on a small scale until demonstration that the project meets the permitting requirements under
the RD&D approval and compliance permit process. This seems consistent with HDR
discussions with the County and WTEG indicating that WTEG intends to start on a limited area
of 4 acres for the first segment of Phase 1 of the project until the system is set up and calibrated
to function successfully prior to moving to subsequent segments of Phase 1. We would expect
that the DEQ will require monitoring data be provided to DEQ for DEQ approval to continue to
additional segments on the lined area of the landfill.
WTEG Technical Review
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Page 22 of 33
Aspects of the RD&D rules include the requirement that the proposed project must have an
identified environmental benefit, based on sound theory supported by valid empirical evidence
that project goals will be achieved, and demonstrate no additional threat to the environment. A
portion of the RD&D guidance is below.
“For an innovative technology to be eligible for consideration and permitting in Oregon, the
proposed RD&D project must be an allowed variance under the Federal Rule and should: (1)
have an identified potential environmental benefit over and above any environmental protection or
benefit realized by implementing already approved plans and operations; (2) be based on sound
technical theory that is supported by valid empirical evidence to confirm that the project goal(s)
will likely be achieved by the proposed technology; and (3) demonstrate that it will pose no
additional risk to human health and the environment beyond that which would result from a landfill
operating under the criteria contained in the existing MSWLF permit and related plan approvals”.
The purpose of the project as stated in the WTEG draft RD&D permit application letter is
restated, below:
The purpose of this demonstration is to provide the County and DEQ with sufficient data to
implement a new approach to landfill gas management. The demonstration is designed provide
the following information:
• That the Subtitle D required depth of leachate over the primary liner not be exceeded,
during or after steam injection;
• That the use of steam injection will result in earlier waste stabilization;
• That steam injection enhances waste stabilization and gas removal;
• That the LFG can be scrubbed and sold as a by-product.
The above listed purpose includes regulatory compliance and project benefits. We would
expect that in addition to continued monitoring of leachate depth on the liner DEQ will also
require monitoring for continued compliance with Title V permitting requirements. Based on
discussions with Mr. Fisher at DEQ, this will at a minimum require surface emission monitoring
in the WTEG operating areas and an approved sampling procedure for the 2013 NSPS Tier 2
reporting. The results of this Tier 2 reporting affect the requirement for LFG collection over the
whole landfill – see discussion in previous NSPS section. In general, DEQ will require that
emissions stay below regulatory limits even with the WTEG expected large increase in LFG
generation.
Given the RD&D (both Oregon and Federal) goals we will expect that DEQ will at a minimum
require monitoring of waste as a means to demonstrate the environmental benefit of the project.
We would expect this will be required through monitored of increased settlement, leachate
quality monitoring, gas monitoring, etc. This may require compilation of baseline settlement
rates, leachate quality information and trends, and gas removal rates
Demonstrating sound technical theory supported by valid empirical evidence to confirm the
project goals will likely be achieved would by definition require that the empirical evidence be
acquired by means of observation or experimentation. It would appear that the bioreactor
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
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Phone (916) 817-4700
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Page 23 of 33
research to date shows that addition of liquids to landfills increases LFG production and waste
stabilization and is therefore similar to the theory of steam injection proposed.
General potential permitting hurdles or fatal flaws
Based on HDR review of provided information and discussions with WTEG, the County, and
regulatory staff noted above it does not appear that there is a fatal flaw that would prevent
WTEG proceeding with the project in a demonstration mode under the current regulations in-
place. Likewise, if the initial segment of the project is approved by DEQ and others requiring
permits and proves successful in meeting and demonstrating the RD&D goals, one would
expect that it would be allowed to continue.
However, we expect that there will be hurdles in permitting and compliance that should be
considered by the County. These include the monitoring and compliance requirements and
potentially public or environmental opposition.
We have included reference to expected minimum monitoring requirements from DEQ to
demonstrate project goals. Those items are not an exhaustive list and DEQ may also require
more monitoring parameters to demonstrate meeting of project goals and benefits in addition to
the compliance monitoring that will need to be continued for the landfill as well as expanded for
the proposed project. Many of the early bioreactor projects required significant monitoring of
many waste parameters (temperature, moisture, etc.) as data was compiled by the USEPA. We
do not expect the same level of those older projects; however, we expect the monitoring will be
a significant increase over the current monitoring projects.
HDR understands from discussions with the County and DEQ that there has been opposition to
the project at public meetings including that from neighbors and other outside groups. We
would expect that this opposition will continue to be a hurdle if the County and WTEG proceed
with the permitting process. We understand that the land use permitting also will include local
policy maker input. The scope of this TM does not include a discussion or evaluation of public
input as it related to permitting and we assume that the County is best suited to assess those
conditions.
Financial Review
HDR performed a review of the financial aspects of the project as proposed by WTEG. The
review was conducted on the financial information provided in WTEG’s Executive Summary
dated February 7, 2013 and supplemental information provided by WTEG from follow-up
questions. This information included:
• Revenue projections;
• Staff and personnel breakdown and estimated costs;
• Capital and Project costs including:
- Estimated total organics;
WTEG Technical Review
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Folsom, CA 95630
Phone (916) 817-4700
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www.hdrinc.com
Page 24 of 33
- Plant and machinery;
- Service equipment;
- Operating costs; and
• Cash flow Year 1 to12.
WTEG’s information was provided based on the steam injection project described in their
February 7, 2013 document and discuss in the Technical Review Section of this Technical
Memorandum. Although HDR has reviewed and analyzed all available WTEG economic
information, for this report we have removed all of these economic figures as they are
proprietary to WTEG and their development efforts. HDR has provided review below by section
of the financial information WTEG provided.
Revenue Projections
In calculating revenues, WTEG assume that 355 tons of organics per day would be available
over a four (4) acre area. They assumed injecting steam into this four (4) acre parcel using
19,880 gallons of water per day. WTEG calculated that the production potential using these
assumptions was to produce 2,556 mmBtu per day of CH4 pipeline quality gas. WTEG also
assumed that they could operate 355 days per year (97.2% availability factor) and garner a
long-term contract starting in Year 1 at $7.00 per mmBtu. This translates into $17,892 per day
or $6,351,660 per year in revenues as shown by WTEG and Table 1. In future years the $7.00
per mmBtu was escalated at 2% per year.
Table 1 - WTEG’s Revenue Projections
As discussed in the Technical Review Section of this Technical Memorandum HDR ran several
landfill gas generating scenarios and arrived at much lower landfill gas generation amounts.
HDR’s opinion is that gas generation at the KLF will not match the estimated quantities
purported by WTEG. However, the steam injection and collection process should not be
detrimental or cause undo harm to the KLF. The greatest technical risk is penetration of the cell
liner, but this can be mitigated similar to installation of conventional landfill gas wells by means
of accurate as-built information and recent survey elevations. The greatest financial risk is the
effect that decreased gas production will have on the WTEG’s published financial information.
HDR has run sensitivities No. 1 and No. 2 below representing lower gas generation figures and
Knott Landfill
Potential Purchase
Product Price Quantity Units Per Day Annually *
CH4 Pipeline Gas 7.00$ 2,556 mmBtu 17,892$ 6,351,660$
355 * Days of Continuous Operation 355 Landfill Organics (tons per day)
19,880 Gal of water/day required 4 Acres Steamed Injected
Revenue Projections
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 25 of 33
how that affects the revenues and overall economics of the project. All sensitivity runs are
discussed below in the section entitled Economic Sensitivities.
WTEG also assumed that the project would operate at a 97.2% availability factor (355 days per
year). We believe for a project of this type, using somewhat new technology a 90% availability
factor might be more appropriate. This represents about 328 days per year of operation and
allows for 2 to 3 weeks of planned downtime for maintenance and 2 to 3 weeks for unplanned
downtime. HDR has run Sensitivity No. 3 to show the how the lower availability affects the
overall economics.
WTEG has assumed garnering a long-term contract for CH4 pipeline quality gas starting in Year
1 at $7.00 per mmBtu. At the time of this report, WTEG has only provided a list of three potential
buyers including: 1) the Northern California Power Agency (NCPA), 2) Noble Americas Energy
Solutions and 3) Direct Biogas. A letter of interest was provided to WTEG by Noble located in
San Diego, California. In addition, a draft gas purchase agreement between NCPA and WTEG
was presented. WTEG indicated that as part of the funding process, WTEG and the investment
group will select the buyer based on credit worthiness and rates. WTEG indicated that in recent
discussions, they have markets for green gas for their fuel cell and LNG customers t hat will pay
$7.00 - $8.00 per mmBtu, however as there is not yet a signed contract for the purchase of the
gas produced at the KLF, the price could fluctuate. HDR has run Sensitivity No. 4 below to
show the affect of the price lowered to $5.00 per mmBtu.
In WTEG’s financial model they have assumed an inflation escalator of 2% per year for
revenues starting in Year 3 of their 12 year projected model and a 3% per year inflation
escalator for expenses starting in Year 3 (some line items were escalated in Year 2 as well). As
no one can accurately predict the future price of CH4 pipeline quality gas, the assumption of a
2% per year escalation cannot be commented upon. However, we believe it is good economic
conservatism to show a lower escalation rate of 2% per year for revenues as compared to a 3%
per year escalation rate for expenses as WTEG has allowed in their projections.
Staff and Personnel Estimates
WTEG has included certain plant staff and administration personnel to operate and manage the
Project. The plant staff includes three general laborers, one each available for all three shifts
during a 24 hour period as well as one Site Engineer available for one shift per day. In addition,
WTEG included one full time General Manger and a half-time IT Specialist and a half-time
Accounting/Payroll Clerk.
Capital and Project Costs
This section contains information on the Plant and Machinery, Service Equipment, Operating
Costs and a Summary as shown below.
Plant and Machinery
WTEG has proposed the following Plant and Machinery items in their financial model.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 26 of 33
• Building;
• PPT Profiling, Steam Injection System, & Gas Collection Installation;
• Biogas Purification and Scrubbers Systems; and
• Inter-Connect and Compression Systems.
WTEG has also included Engineering and Permits costs, Project Development costs and a 10%
contingency of all of the items listed above.
Building
WTEG has included a building in their financial estimate. No details were included to the size,
location or purpose of this building. HDR believes it is reasonable to include a building for the
Project but does not understand the need for a building which appears to be too large and/or
using costly construction. We believe it would be reasonable to build a smaller less expensive
building to house the equipment and some small office space.
PPT Profiling, Steam Injection System, & Gas Collection Installation
WTEG included a detailed breakdown for the cost of PPT Profiling in their February 7, 2013
Executive Summary document. This estimate for PPT Profiling appears reasonable as a
contingency was added to it of 10 percent. There were no costs provided for review for the
Steam Injection System or the Gas Collection System Installation. HDR was only provided a
total for all three cost items; not detailed by item. HDR did not receive any detailed information
on these two system components to comment on the assumed cost of installation. However, it
would appear that this cost may be reasonable, although HDR would have liked to reviewed the
details to the overall cost assumption to verify this.
Biogas Purification and Scrubbers Systems
WTEG provided a detailed cost proposal from Generon IGS, Inc. for providing a Containerized
Membrane System for Biogas Purification & Compression for a Design Product Capacity of
about 2.35 MMSCFD (1,630 SCFM). We have seen other similar systems cost almost 2 to 3
times as much as WTEG’s estimate. However, since this technology is ever evolving and
prices tend to drop as technology evolves and a detailed cost proposal was provided to back up
the cost from Generon IGS, Inc. we assume that this cost is reasonable for this item. However,
the County and WTEG should keep close on the cost of this item as it is installed.
Inter-Connect and Compression Systems
WTEG did not include any details regarding assumptions to the make-up of this total cost. It
would appear that this cost would be reasonable, however HDR would have liked to review the
details to the overall cost assumption to verify that indeed it was reasonable.
Other
This category includes Engineering and Permits, Project Development and a 10 percent
Contingency. Engineering and Permits appears to be reasonable at about 7 percent of the
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 27 of 33
capital costs for engineering, however although permitting for this first phase at the KLT appears
to be straight forward, WTEG will not know for sure until permitting is initiated. Project
Development appears reasonable and WTEG’s use of 10% as a contingency is comparable to
other projects at this stage and size.
Service Equipment
Although WTEG included this line item for Service Equipment in their financial model, no actual
cost was included for this item in WTEG’s financial information.
Operating Costs
WTEG included in their financial information regarding annual operating costs for staff and
personnel as well as operation costs including insurance, legal, utilities, technology license fees,
maintenance, service contracts, and a 10 percent contingency. These annual costs are not
recognized in full in the Cash Flow Year 1 to 12 model until Year 2 when the Project is first
shown to operate full time. It should be noted that the cost for technology license fees are not
included in the annual model. HDR is assuming that this is a one time fee for the Project and will
be included in the Capital Costs for financing.
As discussed above, the staff and personnel costs appear reasonable. So do the insurance,
legal costs, service contracts, and a 10 percent contingency. However, we believe the
maintenance and utilities costs may be on the low side of similar projects we have reviewed
previously. Although this is the case, we believe it is potentially reasonable that the
maintenance cost of this Project could be as low as projected. WTE will need to continuously
monitor these costs to keep them within budget. In addition, the Generon system specifications
provide for feed gas compression for the PSA system, as well as product gas compression to
pipeline pressures. This is stated to require 2,000 horsepower compression capacity. Basic
order of magnitude calculations with generous power-factor assumptions and electricity rates
yield electricity costs on the order of $500,000 per year to run this process. We believe this
figure is reasonable; however WTEG needs to monitor their power and water usage.
Cash flow Year 1 to12
WTEG included a cash flow model for Years 1 to 12. WTEG’s model shows that the Project
would be only operating at about 50 percent availability during Year 1. Escalation for inflation
appears for Revenues starting in Year 3, while escalation for inflation for the Operating costs
begins in Year 2 and 3, depending on the line item.
Also as discussed above, the technology license fees are not included in the annual model.
Neither is any representation of the capital costs for this Project in the form of a debt service or
other financial obligation. Although we understand that the County will not be charged for any
capital costs to develop, construct or finance the infrastructure for the Project, the Project will
incur these costs and they need to be accounted for in the cash flow to show a true
representation of the revenues and expenses (including debt service representing the
capitalized items that should be reflected in an annual amortized amount). HDR has run
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 28 of 33
Sensitivity No. 5 below to show the affect of adding the expenses for capital to the cash flow
model.
Economic Sensitivities
As discussed above, five (5) sensitivities to WTEG’s base case financial model were run by
HDR to determine how they would affect the overall economics. The actual WTEG model was
used running the different assumptions described below. The output for each sensitivity will be
shown using the Year 1 to 12 Cash Flow Model. The scenarios include:
• Sensitivities No. 1 and No. 2 representing two separate reasonable lower gas
generation figures and how these affect the revenues and overall economics of the
project;
• Sensitivity No. 3 representing how a lower but reasonable availability of 90% affects the
overall economics;
• Sensitivity No. 4 representing the affect if the contract price of pipeline CH4 were
reduced from $7.00 per mmBtu to $5.00 per mmBtu; and
• Sensitivity No. 5 representing the affect of adding the expenses for capital (which are
real costs that need to be account for) to the cash flow model.
Sensitivity No. 1
As discussed in the Technical Review Section, WTEG estimated approximately 2,556
mmBtu/day of pipeline quality gas from a 4-acre parcel of the KFL using their steam injection
process. WTEG also predicts a minimum of 60% methane in the landfill gas generated.
Conversion using the nominal heating value of methane at approximately 1,000 Btu/cubic foot
yields an estimated raw landfill gas flow rate of 2,958 cubic feet per minute (cfm) at 60%
methane. For Sensitivity No. 1 HDR utilized Scenario 3 as shown in the Figure 1 graph in the
Technical Review Section. This Scenario represents recirculation of liquids and the maximum
LandGEM field bioreactor modeling values possible for K and Lo 16. Modeling of this scenario
shows that the peak landfill generation would be in 2013 with 1,994 scfm at 60% methane. This
translates to approximately 1,723 mmBtu/day of pipeline quality gas being generated.17
Although this is the maximum value modeled by LandGEM for a field bioreactor condition, it is
still less than the 2,556 mmBtu/day WTEG has used in modeling their gas revenues. This
sensitivity will only affect the base case by lowering the amount of gas produced and the
revenues generated.
Sensitivity No. 2
As discussed for Sensitivity No. 1, using the information provided by WTEG and the nominal
heating value of methane at approximately 1,000 Btu/cubic foot yields an estimated raw landfill
gas flow rate of 2,958 cubic feet per minute (cfm) at 60% methane. For Sensitivity No. 2 HDR
utilized Scenario 2 as shown in the Figure 1 graph in the Technical Review Section. This
Scenario represents recirculation of liquids and the industry-published bioreactor parameters for
16 Note that this is roughly 3 times the Miramar pilot study field results and Scenario 2 of Figure 2. 17 1,994 scfm * 600 Btu/scf * 1 Btu/1,000,000 mmBtu * 1,440 min/day = 1,723 mmBtu/day
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 29 of 33
K and Lo. Modeling of this scenario shows that the peak landfill generation would be in 2013
with 1,021 scfm. This translates to approximately 882 mmBtu/day of pipeline quality gas being
generated.18 This is the flow rate using industry published values for field bioreactors; however
this amount is much less than the 2,556 mmBtu/day WTEG has used in modeling their gas
revenues. This sensitivity will only affect the base case by lowering the amount of gas produced
and the revenues generated.
Sensitivity No. 3
WTEG assumed that the project would operate at a 97.2% availability factor (355 days per
year). We believe for a project of this type, using somewhat new technology a 90% availability
factor is more appropriate. Running this sensitivity would mean that the facility would be less
available and produce less pipeline gas for sales than WTEG originally assumed. All other costs
such as personnel, insurance, legal, etc. would remain the same except for utilities. For this
sensitivity HDR assumed reducing both the product pipeline gas and the utilities usage from
97.2% availability to 90% availability. The “Net Revenues” remains positive in this sensitivity.
Sensitivity No. 4
WTEG assumes that they will be able to garner a long-term contract for pipeline CH4 at starting
in Year 1 at $7.00 per mmBtu. There are currently no contracts signed at this price. This
sensitivity shows the affect on the revenues and the overall economics by using a figure of
$5.00 per mmBtu for the pipeline gas sold. Only the rate of cost for the sales of gas is modified
for this sensitivity. The amount of gas assumed to be produced by WTEG is used in this
sensitivity. The “Net Revenues” remains positive in this sensitivity.
Sensitivity No. 5
HDR modeled Capital costs by amortizing them to an average annual payment through
amortization of the costs using a 5 percent interest rate and a 12 year term. This would
decrease the net cash flow each year by almost half. HDR has added this amount to the
sensitivity. The amount of gas assumed to be produced by WTEG is used in this sensitivity.
HDR believes this amount should be added to all sensitivities. This reduces all “Net Revenues”.
Financial Review Summary
In summary, HDR believes that all sensitivities and the Base Case should include the required
cost for the Capital equipment and support costs. These need to be taken into account in most
18 1021 scfm * 600 Btu/scf * 1 Btu/1000000 mmBtu * 1440 min/day = 882 mmBtu/day
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 30 of 33
any cash flow to get an accurate reading of the overall economics. Although as we understand,
the County will not be paying for any of these Capital costs, the cost will still be a part of the
overall economics and the Project must be looked at with a full accounting of costs and
revenues. Accounting for these Capital costs shows that the Base Case and all other
sensitivities should be lowered.
Sensitivities using lower gas generation rates have the most impact on the overall economics. If
the Project does not generate the amount of product gas for sale as WTEG has proposed, the
Project will have a difficult time being economic feasible. One other issue that can cause an
issue with the Project being economically feasible is the price that WTEG contracts for the
pipeline gas sales price. The combination of price per mmBtu and the amount of mmBtu’s
produced drives the economic feasibility.
Risk Allocation Review
HDR has included potential risks below area of review including technological,
permitting/regulator financial as well as contractual risks.
Technical Risks
Technical risks were assessed by reviewing WTEG’s technical considerations for the Project
and all available supporting documentation and assumptions. HDR concludes that the following
potential risk should be taken into account by the County when considering this project.
• HDR’s opinion is that gas generation at the KLF will not match the estimated quantities
purported by WTEG. However, the steam injection and collection process should not be
detrimental or cause undo harm to the KLF. The greatest technical risk is penetration of
the cell liner, but this can be mitigated similar to installation of conventional landfill gas
wells by means of accurate as-built information and recent survey elevations.
• WTEG proposes an optimal liquid requirement of approximately 5,000 gallons/acre/day.
The issue of note for the proposed WTEG project at the KLF has to do with the sourcing
of this quantity of liquid. KLF currently has approximately 38 acres of lined cells which
generate a normalized annual average of approximately 287,000 gallons/month (9,500
gallons/day). This quantity is far short of the 20,000 gallons per day for a 4-acre steam
injection tract
• The proposed project does not provide the County with a working gas collection system
after WTEG leaves each 4-acre tract. The County will be relying upon WTEG’s
assertion that “all” gas has been extracted from each 4-acre tract. However, once
WTEG leaves an area, fugitive gas emissions could be higher than prior to the project
(due to the effects of the steam injection). The County should consider how this gas will
be collected and controlled.
• The proposed project does not provide for increasing flaring capacity at the site to
handle the increased gas production. Industry standard practice is that the back-up
control device has sufficient capacity to handle all LFG collected.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 31 of 33
Permitting/Regulatory Risks
Discussion with regulatory agencies (see Permitting Section) have left open the possibility of
triggering enhanced surface monitoring (at a minimum) and/or adjustment of New Source
Performance Standards (NSPS) Tier 2 reporting. Although regulatory agencies seem receptive
to the process there are still compliance risks to the County as the permit holder if WTEG does
not operate the LFG collection system adequately to maintain compliance.
Financial Risks
Financial risks were assessed by reviewing WTEG’s financial modeling for the Project and all
available supporting documentation and assumptions. HDR concludes that the following
potential risk should be taken into account by the County when considering this project.
• We understand that WTEG intends to obtain private financing for this project. WTEG did
not provide any financial or financing information for review 19. As such, the County
should require WTEG to provide a letter from their financial institution representing their
support for this project. The ability to finance this project will be a direct factor affecting
the viability of the project, and therefore a relative potential risk to the County.
• HDR has reviewed the amount of gas WTEG estimates will be produced in the Project.
From our analysis and detailed modeling we do not agree with the amounts being
estimated by WTEG, we believe the amount generated will be between approximately
35 and 65 percent of the 2,556 mmBtu/day estimated by WTEG. This may leave the
Project economically unfeasible.
• Although WTEG has indicated that they have been in discussions and negotiating for a
sales price of the pipeline gas, not contract has been signed to date. WTEG has used a
price of $7.00 per mmBtu which may be reasonable in the current market, however if the
contract is signed for much less than this amount, such as $5.00 per mmBtu, the Project
may have difficulties being financially feasible.
• WTEG should have included the required cost for the Capital equipment and support
costs in their Cash Flow Model. These need to be taken into account in most any cash
flow to get an accurate reading of the overall economics. Although as we understand,
the County will not be paying for any of the Capital costs, the cost will still be a part of
the overall economics and the Project must be looked at with a full accounting of costs
and revenues.
Contractual Risks
HDR reviewed a draft contract between WTEG and the County that was provided by the County
via email in October 2012. It contained many track changes comments, edits and clauses that
were pending and need to be resolved between the parties. Upon review HDR identified
potential risks and areas of concern and has the following recommendations to the County
regarding the agreement reviewed:
19 The review of the viability of financing of the WTEG proposed project is not within HDR’s scope of services for
the project involving developing this TM.
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 32 of 33
• Term of 15 years may be too long; needs to be consistent with term for payback of
capitalized equipment
• Clause for two automatic extensions should be just one extension based upon their
performance over the original term of the agreement.
• This agreement should only define Phase 1 as this project needs to be proven before
Phases 2 or 3 are considered.
• Definitions – specifically for locations, “commercial operations date”, “gas rights” (not a
good term).
• Since this is a “research and development” type project, the County should not allow
delegation of this contract unless consent is granted by both parties. The language
“such consent shall not be unreasonably withheld” from the contractor makes it open for
delegation to be made to anyone the contractor chooses and not who the County
approves of.
• The cure period should be consistent and be not more than 30 days without the written
approval of the County.
• The contractual clause; “County reserves the right to suspend operation of the
technology at any time should continued operation pose a significant threat to human
health or the environment.” Should include the added words, “at any time”.
• The 2 year suspension clause should be reduced to one year so the County is not tied to
the Contractor and can seek other technologies to handle the landfill and its gas. During
the one year suspension, the Contractor should be required to report progress towards
regaining operations on a periodic basis.
• County and Contractor cooperation should have County added to the clause so that the
County is cooperated with as well.
• Environmental attributes such as tax credits, grants, and rebates can be provided to the
Contractor; however the County should still be able to collect carbon credits. If not , the
County should use their potential collection of carbon credits when negotiating the final
financial terms.
• The contract should include a clause for a 3rd party review if parties do not agree on
issues pertaining to the contract.
• The WTEG requirement for 500 hours of the County’s employee is almost ¼ quarter
time employment. If this is required by the Contractor and the County is amenable to
this clause the County should include an additional clause that warrants that the
employee or the County is not responsible for any damages created by the employee as
directed by the Contractor.
• Need to have protection in the contract that Contractor’s obligations in no way interfere
with County’s responsibilities to operate and maintain the Landfill according to industrial
standards and DEQ regulations.
• Under County Obligations the following clause should be edited as shown. “Operate the
landfill in a manner that that follows the County’s needs and protocols and does not
hinder Contractor’s LFG enhancement activities and that does not interfere with the
System, provided that such requests of Contractor do not cost the County additional
monies, cause a violation of DEQ operational permits or deviate from the standards of
good industry practices.”
WTEG Technical Review
HDR Engineering, Inc. 2365 Iron Point Road, Suite 300
Folsom, CA 95630
Phone (916) 817-4700
Fax (916) 817-4747
www.hdrinc.com
Page 33 of 33
• This contract should be based upon what has been landfilled to date and does not
include the use of any new materials that is provided to the Landfill. The County has the
right to direct its waste and potential divertible materials as it wishes.
• Access to the site should be limited to only the hours the County is permitted for
operations.
• Contractor should not violate any permit conditions through operation of their project. If
Contractor triggers revision to the County’s Title 5 permit, the Contractor shall be
responsible for all costs.
• Financial terms should be negotiated to include a base payment figure by the Contractor
as suggested at $20,000 per month. However if “net revenues” from the project
increase above $200,000 per month, the County shall, in addition to the base payment
of $20,000 per month, garner a royalty payment of 10% of the net revenues from the
project. The term “net revenues” should be defined in the agreement addressing all
costs to be reflected for reducing the “gross revenues” to “net revenues”.
• Collection system requirements should be include, or clearly state what is not included.
The collection system should be subject to County approval.
• County should be aware that WTEG systems will not be in compliance with NSPS
regulatory criteria if that should be become a requirement.
• Need clear delineation of responsibility for monitoring and data collection that may be
required to comply with RD&D permit (or other permitting).
• Flare capacity – highly recommend the site have flare capacity for ALL collected
gas. Best management practice and regulatory requirement in case all conversion
technology goes down.
• Need milestones tied to termination, so that project cannot sit undeveloped for too long
waiting for WTEG funding or end-user power purchase agreement negotiations.
• Not clear if County will allow WTEG to utilize/sell the LFG currently collected in the
County system
• Language that clearly denotes space for the Contractors operations. Usually denoted by
a map, with a simple sublease for a nominal ($1/year) fee.
• If for any reason, the collection system in that area becomes required by regulation
(NSPS most likely), the County will need access to monitoring data.
• Recommend County petition to keep all “subsurface” attributes upon termination of the
contract. This will preserve a collection system in place if WTEG is displaced.
• Recommend section on migration control and surface emissions and odors as primary
goals of County and that WTEG may be required to modify operations to address (and
these modifications could lead to less LFG conversion and sale). Language can be
negotiated.
ATTACHMENT A
Figure 1 LandGEM Model Summary and Assumptions
Component1
Percent by
Weight
Wet
Faction per
Kg MSW
Moisture
Content
(% by wt)2
Dry
Faction
100 Kg
Rate, (yr
based
M × k × η (m3/dry
M × L
MC
MSW-Food Waste 9.0% 70.0% 13.63 122.67 220 594
MSW-Paper 26.4% 5.5% 21.56 569.18 136 3393
MSW-Yard Waste 7.2% 60.0% 18.73 134.86 144 414
MSW-Wood 1.2% 20.0% 7.16 118 113
MSW-Misc 16.2% 5.0% 0.05 170 2616
C&D-Wood5 40.0% 20.0% 7.16 286.40 118 3776
Total 100.0% 78.88 10,906
Job No. No.
HDR Engineering, Inc.
Project Deschutes Computed KS Date 1/24/2012
Subject Calculation of site specific "Lo" & Lab "k" Checked JM/CL Date 2/15/2013
Task Sheet 1 Of 3
The efficiency of actual landfill compared to laboratory scale experiment (η)= 100% (assumed variable)
t,w lab t,d o
C&D (Wood) fraction = 40 %
MSW fraction = 60 %
Bulk waste reaction rate = 11.23 yr-1
Bulk waste L0 = 138 m3/dry Mg
Bulk waste L0 = 109 m3/wet Mg
Notes
1. Waste composition is based on Table 4-2 of the "Solid Waste Engineering Principles & Mgmt Issues" by Tchobanoglous et. al (1997) - Book Published by McGraw-Hill.
2. Moisture content is based on Table 4-3 of the "Solid Waste Engineering Principles & Mgmt Issues" by Tchobanoglous et. al (1997) - Book Published by McGraw-Hill.
3. Reaction rate (k) values are based on Lab scale experiments performed by Cruz et. al. (2010) and Owens et. al. (1993).
4. Methane generation potential (Lo) values are based on Cruz et. al. (2010), Eleazer et. al. (1997), Owens et. al. and Staley et. al. (2006). The average is used as
applicable when reported.
5. Misc wastes consists of Textile, Leather, Plastics, Metals and residue. These components are not readily biodegradable but have high energy content. Therefore, k and
Lo were picked based on LandGEM.
6. Per 12-27-12 email from Timm Shimke: "I estimate that we average about a 60% MSW and 40% C&D split although our C&D stream contains very little inert materials.
Rock, dirt, asphalt and concrete have always been directed to other disposal sites." Therefore, C&D Waste is assumed as primarily wood.
References
1. F. De La Cruz, M. Barlaz, "Estimation of Waste Component-Specific Landfill Decay Rates Using Laboratory-Scale Decomposition data", Environmental Science and
Technology, vol. 44, no. 12, 2010, pp. 4722-4728.
2. W. Eleazer, W. Odle ΙΙΙ, Y. Shengwang, M. Barlaz, "Biodegradability of Municipal Solid Waste Components in Laboratory-Scale Landfills", Environmental Science
and Technology, 31, 911-917, 1997.
3. B. Staley, Fangxiangxu, S. Cowie, M. Barlaz, G. Hater, "Release of Trace Organic Compounds during the Decomposition of Municipal Solid Waste Components",
Environmental Science and Technology, 40, 5984-5991, 2006.
4. J. Owens, D. Chynoweth, "Biochemical Methane Potential of Municipal Solid Waste (MSW) Components", Water Science and Technology , Vol.27, No. 2, pp. 1-14,
1993.
Job No. No.
HDR Engineering, Inc.
Project Deschutes Computed KS Date 1/24/2012
Subject Modeling Scenarios Checked JM/CL Date 2/15/2013
Task Sheet 2 Of 3
HDR Assumptions
Heat Content of Methane = 1000 BTU/scf
Percent Methane in Landfill Gas = 60%
Claimed Parameters by the Developer
Claimed landfill gas flowrate = 2556 mmBTU/day COLLECTION FROM 4 ACRE AREA
Landfill gas (LFG) flowrate = 2,958 scfm COLLECTION FROM 4 ACRE AREA
To evaluate the spectrum of landfill gas generation, five scenarios were considered for LandGEM modeling. The Methane Generation Rate (k) and Methane
Generation Potential (Lo) for the five scenarios were developed as discussed below:
Scenario No. Description k (per yr) Lo (m3/Mg)
1
Scenario is based on typical landfill conditions used to model LFG flowrates anticipated to design
initial LFG collection systems at landfill facilities (AP-42 Parameters). Assumes NO re-circulation
of liquids.
0.04
100
2
1 Scenario is based on published landfill bioreactor conditions. k value is based on published data
and Lo value is developed based on Deshutes site specific conditions2 (see k & L sheet)
0.30
109
3 Scenario is based on LandGEM maximum bioreactor values (wet conditions and high energy waste
types) - a hypothetical high energy bioreactor 0.70
170
4
Scenario is based on lab maximum conditions specified on k & L Sheet 11.23
109
5 Scenario represents absolute maximum methane generation. k value developed based on lab data &
Lo is based on LandGEM maximum 11.23
170
Notes:
1. k value is based on: Faour, Ayman A., Reinhart, Debra R., and You, Huaxin. (2007) “First‐order kinetic gas generation model parameters for wet landfills.”
Waste Management 27 (2007), 946–953.
2. k & L Sheet calculates laboratory conditions. Note that Lo is inherent property of waste material (based on constituents) and will remain same for waste
regardless of lab or field conditions.
0
Job No. No.
HDR Engineering, Inc.
Project Deschutes Computed KS Date 1/24/2013
Subject LandGEM Results Checked JM/CL Date 2/15/2013
Task Sheet 3 Of 3
Proposed LFG Generation from 4-Acre Tract at KLF
LFG Generation Spectrum
4,500
4,000
3,500
3,000
2,500
2,000
1,500
1,000
500
0
Year
Scenario 1 - Typical AP-42 parameters K (methane degradation rate) & Lo (methane generation potential). No recirculation of liquids.
Scenario 2 - Recirculation of liquids. Published field bioreactor parameters K and Lo
Scenario 3 - Recirculation of liquids. Maximum field bioreactor LandGEM values for parameters K and Lo
Scenario 4 - Maximum lab values for parameters K and Lo. Optimum lab conditions for site-specific KLF waste.
Scenario 5 - Absolute maximum values of Scenarios 1 through 4 for parameters K and Lo. Optimum lab conditions for generic MSW.
Proposed - Proposed value of 2,958 scfm based on WTEG estimate of 2,556 mmBtu/day at 60% methane.
ATTACHMENT B
Figure 2 LandGEM Model Summary and Assumptions
Component1
Percent by
Weight
Wet
Faction per
Kg MSW
Moisture
Content
(% by wt)2
Dry
Faction
100 Kg
Rate, (yr
based
M × k × η (m3/dry
M × L
MC
MSW-Food Waste 15.0% 70.0% 13.63 204.45 220 990
MSW-Paper 44.0% 5.5% 21.56 948.64 136 5655
MSW-Yard Waste 12.0% 60.0% 18.73 224.76 144 689
MSW-Wood 2.0% 20.0% 7.16 14.32 118 189
MSW-Misc5 27.0% 5.0% 0.05 170 4361
Total 100.0% 78.13 11,883
Job No. No.
HDR Engineering, Inc.
Project Miramar Computed KS Date 1/30/2013
Subject Calculation of site specific "Lo" & Lab "k" Checked JM/CL Date 2/15/2013
Task Sheet 1 Of 3
The efficiency of actual landfill compared to laboratory scale experiment (η)= 100% (assumed variable)
t,w lab t,d o
Bulk waste reaction rate = 13.94 yr-1
Bulk waste L0 = 152 m3/dry Mg
Bulk waste L0 = 119 m3/wet Mg
Notes
1. Waste composition is based on Table 4-2 of the "Solid Waste Engineering Principles & Mgmt Issues" by Tchobanoglous et. al (1997) - Book Published by McGraw-Hill.
2. Moisture content is based on Table 4-3 of the "Solid Waste Engineering Principles & Mgmt Issues" by Tchobanoglous et. al (1997) - Book Published by McGraw-Hill.
3. Reaction rate (k) values are based on Lab scale experiments performed by Cruz et. al. (2010) and Owens et. al. (1993).
4. Methane generation potential (Lo) values are based on Cruz et. al. (2010), Eleazer et. al. (1997), Owens et. al. and Staley et. al. (2006). The average is used as
applicable when reported.
5. Misc wastes consists of Textile, Leather, Plastics, Metals and residue. These components are not readily biodegradable but have high energy content. Therefore, k and
Lo were picked based on LandGEM.
References
1. F. De La Cruz, M. Barlaz, "Estimation of Waste Component-Specific Landfill Decay Rates Using Laboratory-Scale Decomposition data", Environmental Science and
Technology, vol. 44, no. 12, 2010, pp. 4722-4728.
2. W. Eleazer, W. Odle ΙΙΙ, Y. Shengwang, M. Barlaz, "Biodegradability of Municipal Solid Waste Components in Laboratory-Scale Landfills", Environmental Science
and Technology, 31, 911-917, 1997.
3. B. Staley, Fangxiangxu, S. Cowie, M. Barlaz, G. Hater, "Release of Trace Organic Compounds during the Decomposition of Municipal Solid Waste Components",
Environmental Science and Technology, 40, 5984-5991, 2006.
4. J. Owens, D. Chynoweth, "Biochemical Methane Potential of Municipal Solid Waste (MSW) Components", Water Science and Technology , Vol.27, No. 2, pp. 1-14,
1993.
Job No. No.
HDR Engineering, Inc.
Project Miramar Computed KS Date 1/30/2013
Subject Modeling Scenarios Checked JM/CL Date 2/15/2013
Task Sheet 2 Of 3
HDR Assumptions
Waste volume based on 1 Acre Cubed Cell & 50 ft depth = 80,667 cy
Density of landfilled waste = 1890 lb/cy
Total Design Capacity of 1 Acre Cell = 76,230 tons
Assumed Capacity of the Cell in Years = 1 Year (very conservative assumption)
Parameters Provided by the Developer
Landfill gas flowrate with 1,500 Gal/day water = 228 scfm COLLECTION FROM 1 ACRE AREA
Landfill gas flowrate with 5,000 Gal/day water = 1,080 scfm COLLECTION FROM 1 ACRE AREA
Methane Content = 66 %
To evaluate the spectrum of landfill gas generation, five scenarios were considered for LandGEM modeling. The Methane Generation Rate (k) and Methane
Generation Potential (Lo) for the five scenarios were developed as discussed below:
Scenario No. Description k (per yr) Lo (m3/Mg)
1
Scenario is based on typical landfill conditions used to model LFG flowrates anticipated to design
initial LFG collection systems at landfill facilities (AP-42 Parameters). Assumes NO re-circulation
of liquids.
0.04
100
2
1 Scenario is based on published landfill bioreactor conditions. k value is based on published data
and Lo value is developed based on Deshutes site specific conditions2 (see k & L sheet)
0.30
119
3 Scenario is based on LandGEM maximum bioreactor values (wet conditions and high energy waste
types) - a hypothetical high energy bioreactor 0.70
170
4
Scenario is based on lab maximum conditions specified on k & L Sheet 13.94
119
5 Scenario represents absolute maximum methane generation. k value developed based on lab data &
Lo is based on LandGEM maximum 13.94
170
Notes:
1. k value is based on: Faour, Ayman A., Reinhart, Debra R., and You, Huaxin. (2007) “First‐order kinetic gas generation model parameters for wet landfills.”
Waste Management 27 (2007), 946–953.
2. k & L Sheet calculates laboratory conditions. Note that Lo is inherent property of waste material (based on constituents) and will remain same for waste
regardless of lab or field conditions.
1 ca pa ame e me degrada on a e &me a po en a No ec a o qu d
Job No. No.
HDR Engineering, Inc.
Project Miramar Computed KS Date 1/30/2013
Subject LandGEM Results Checked JM/CL Date 2/15/2013
Task Sheet 3 Of 3
2,500
Miramar Pilot Study LFG Generation from 1-Acre Tract
LFG Generation Spectrum
2,000
1,500
1,000
500
0
Year
Scenario 1 - Typical AP-42 parameters K (methane degradation rate) & Lo (methane generation potential). No recirculation of liquids.
Scenario 2 - Recirculation of liquids. Published field bioreactor parameters K and Lo
Scenario 3 - Recirculation of liquids. Maximum field bioreactor LandGEM values for parameters K and Lo
Scenario 4 - Maximum lab values for parameters K and Lo. Optimum lab conditions for site-specific KLF waste.
Scenario 5 - Absolute maximum values of Scenarios 1 through 4 for parameters K and Lo. Optimum lab conditions for generic MSW.
Observed - Observed flow of 228 scfm at Miramar Pilot Study reported by WTEG after adding 1,500 gal/day steam injection.
Claimed - Claimed possible flow of 1,080 scfm at Miramar Pilot Study. Theoretical addition of 5,000 gal/day steam injection. Not actually realized.
ATTACHMENT C
Telephone Conversation Record - Joe Gingerich, Oregon DEQ,
12/11/2012
Project: Deschutes Co LFGTE Steam Injection
Review
Telephone Record
Project No: 000102.0000195546
Date: 12/11/12 Subject: County-WTEG steam injection proposal
Call to: Joe Gingerich, OR DEQ Phone No: 503-236-5563
Call from: Mark Urquhart, HDR Phone No: 916-817-4933
Discussion, Agreement and/or Action:
Called Joe after return call from telecommuting. I introduced myself and discussed that I wanted his
thoughts on permitting requirements for project. Summary of feedback and discussions is below:
1. The unlined phases of the project he would expect would be difficult if not impossible to permit
under RD&D. RD&D would cover recirculation and potentially injection into lined landfill.
2. OR is an “approved” state under Federal regulations and can issue permits under RD&D. The
Columbia Landfill has an RD&D permitted project. When I asked if he thought there might be
some USEPA involvement he thought not, as DEQ has authority to issue RD&D permit without
USEPA oversight.
3. Joe said from what he is familiar with about this project it sounds like it may be a good idea if it
makes the landfill decompose and become less of a threat to environment sooner. He said he
may support “helping to make a good idea happen” as long is it protects the environment
according to permits.
4. I asked about additional emission monitoring given increase in gas production and he said that
would be handled under the Title V permitting. That is all under DEQ but Mark Fisher of the
Bend office would handle the air permitting aspects.
5. Joe said that he would see the process as an “iterative” process where the project would start
small and then if successful could be continued.
6. Joe noted that “we have neighbors” that are concerned about health impacts. He that the air
emissions compliance aspects would have to be addressed.
7. Joe said he is comfortable about doing a project such as this at the Knott Landfill because it is
well designed. It has “overkill” in a liner drainage system with large rock and a drainage net and
good LCRS and liner slopes. He would expect very little head on the liner.
8. When I asked about timing he said that the permit renewal for this site (only needed when
changes) has been in the works for a while and the thinking may be to wait until the WTEG gets
bundled in to process the renewal. He said that it would be possible to hold one hearing for the
permit renewal covering both air quality and solid waste issues. Timing to write the permit may
be 60 to 90 days but if it gets controversial via public hearings that it is hard to gauge the timing.
ATTACHMENT D
Telephone Conversation Record - Mark Fisher, Oregon DEQ,
1/30/2013
Project: Deschutes Co LFGTE Steam Injection
Review
Project No:
Telephone Record
Date: 1-30-13 Subject: County-WTEG steam injection proposal
Call to: Mark Fisher, Oregon DEQ, Air Permitting Phone No: (541) 633-2022
Call from: Joel Miller and Mark Urquhart, HDR Phone No:
Discussion, Agreement and/or Action:
HDR (Mark Urquhart and Joel Miller) spoke with Mark Fisher of the Oregon DEQ about the proposed WTEG
project. Specifically focused on the steam injection and the emissions units anticipated for “Phase 1” project
defined by WTEG. Summary of feedback and discussions is below:
Agenda (and associated discussions):
1. Introductions
2. Clarification of current air permitting status
a. Title V
b. Tier 2
c. Notice of Intent to Construct
d. Pending RD&D Application (not yet submitted)
3. Question: Are there any current compliance issues with KLF? If so what is the status and
requirements. Might any affect the WTEG project?
Mark Fisher stated that there have been recent odor complaints from neighbors. Attributes this to the
inability of the site to collect all of the LFG being generated because flare capacity is too small. Also
stated that the landfill is a pro-active permittee and that no enforcement actions have been taken for this
odor complaint.
4. Discussion of future WTEG initial startup period and “Phase 1” WTEG project (to be proposed under
RD&D application)
Discussion of the role of the RD&D application and the preferred permitting mechanism. Mark stated that
all RD&D permitting is handled from the Solid Waste Group (Joe Gingerich), but that certain conditions
might be introduced from the air group (mentioned additional surface emissions).
Mark stated that the preferred method for permitting these activities through the air group is by means of
a Notice of Intent to Construct (Form ND-901). This should be completed in conjunction with RD&D
application. Title V permit would not be modified until next renewal. The Notice of Intent to Construct will
be reviewed against established emission limits for the site (as set by the existing Title V permit).
5. Proposed potential additional emission sources/units for WTEG Phase 1 Project
a. Gas-fired boiler (heating of leachate)
b. Generon Scrubber – Carbon dioxide removal and emissions (assume not sequestered).
Current estimate of up to 1,775 scfm carbon dioxide emissions.
c. Front and back end compression will be electric – assume no emissions.
d. Possible increase in flared LFG when processing units are down.
e. Possible IC engine generator (not clear if this is part of project) (may invoke Subpart ZZZZ
regulations)
6. EPA GHG Reporting Rule – assume no change – must monitor collected and destroyed gas.
Mark noted that Oregon has their own GHG Reporting Rule in addition to the Federal rule.
7. Issue/Question: will the enhanced generation of LFG in controllable areas of the landfill (4-acre
tracts) affect the NSPS 50 Mg/yr NMOC limit (for the entire landfill), or will the requirement for
installation of a GCCS on the entire landfill still be governed by the Tier 1 and Tier 2 reporting (as
normal).
Mark stated that, at a minimum, the existing Tier 2 Report would require modification or the new Tier 2
Report (due in 2013) would need to take LFG samples from the steam injection areas. Discussion was
not conclusive on how the NMOC value would affect the Tier 2 Report or if additional modifications to the
report would be required based on the proposed LFG generation rates in these areas. Tier 2 Report
relies on NMOC concentration in the LFG (likely not affected by steam injection) and estimated quantity of
LFG to estimate a yearly NMOC emission rate. Tier 2 report also governs the requirement for a landfill to
install a landfill gas collection and control system (on the whole landfill).
8. Question: RD&D permit proposes surface emission monitoring in initial stages. Will this be required
through build-out Phase 1 enhancement of LFG, or will this also continue to be governed (for the
entire landfill) by the Tier 1 and Tier 2 reporting (as normal).
Mark stated that, at a minimum, likely requirement would be for surface emission monitoring on the
current 4-acre steam injection area as well as the previous 4-acres. This would likely be a condition of
approval.
Additional Discussion:
Mark stated that the de-minimis carbon dioxide emissions are 2,766 tons/year at this site. IF WTEG would
like to install a scrubber that emits carbon dioxide, the emission rate may be an issue.
Mark stated that surface emissions monitoring on the steam injection areas would be a likely condition on
approval
Mark stated that upgrade of a flare system would be required to have capacity for all collected LFG (even if
flare is only used as backup). This would need to be addressed in the Notice of Intent to Construct.
WASIE
to
TO: MR. TIMM SCHIMKE
DESCHUTES COUNTY DIRECTOR OF SOUD WASTE
SUBJECT: RESPONSE TO HDR TECHNICAL REVIEW
DATE: APRIL 18,2013
This memorandum is in response to the HDR Engineering, Inc. (HDR) Technical
review of the proposed Landfill Stabilization Project (the "Project") at the Deschutes
County Knott Landfill (KLF).
WTEG understands HDR's concern about the possibility that gas generation rates
may not be as high as WTEG expects. HDR's only source of comparison is a
typical bioreactor approach to increased gas production. HDR and the County do
not have experience with the proposed "steam injection" which generates the
increased gas production predicted. Based on our prior experience, WTEG expects
to perform as projected.
WTEG has requested a RD&D permit status to record gas productions, monitor and
assure public health and safety, as well as, compliance with all regulatory
agencies. This will allow WTEG to demonstrate to the County and the DEQ the
process, in a safe and environmentally responsible manner. WTEG is pleased that
HDR has concluded that our proposal will not increase any environmental or health
risks at the landfill.
8 Corporate Park. • SUite 300 • Irvine, California 92018 • (949) 274-9634
WASTE to
WTEG has thoroughly vetted the "Steam Injection" process with its investment
groups to obtain funding from several sources. It should be clear that the financial
risk will be borne by the investment group and not by the County.
Operationally, all areas of the landfill will maintain compliance at all times. WTEG
will work closely with the County and DEQ to monitor the landfill during all phases
of operation. In addition, WTEG will also continue to conduct Piezo-Penetrometer
Tests (PPT) to monitor progress and check for gas migration as the landfill stabilizes,
including those areas that have been treated. Existing wells that are not performing
correctly in the gas collection system will be replaced as we monitor the system and
oxygen levels. As described in the RD&D permit, the DEQ and County will determine
the compliance data to be collected and monitored, pre and post project.
WTEG agrees with HDR's assessment of flare capacity. Permitting requires a backup
method with the capacity to destroy the collected gas. WTEG will increase the backup
flare capacity to be compliant, or use the gas collected in another approved method. For
example, WTEG has not determined whether the Project will generate its own power or
purchase power from the grid. If WTEG elects to generate its own power, that same
generator can be used in conjunction with the existing flare to consume collected gas
during an emergency shut-down.
WTEG agrees that no one can predict the future price of CH4 pipeline quality gas in
today's market. It has never been our intent to rely solely upon this method to generate
sustained revenue generation. WTEG and County are evaluating much stronger off-take
products (not covered in HDR analysis) which will significantly increase revenue and
mitigate risk. Some of this technology is currently being developed and funded by the
same investment groups that have expressed interest in the KLF project.
8 Corporate Park. Suite 300 • Irvine, califomia 92018 • (949) 274-9634
WASIE to
WTEG believes the risks identified by HDR can be mitigated through contract. WTEG
and County will continue to work together to finalize a contract that will address these
pOints and allow WTEG to move into a "funding" phase. WTEG appreCiates the due
diligence done by the County and HDR as we move forward.
Regards,
Randy Lutz
L. Randall Lutz
Waste to Energy Group, LLC.
Chief Executive Officer
949.274.9634 Office
949.293.9740 Mobile
8 Corporate Park. Suite 300 • Irvine, califomia 92018 • (949) 274-9634