Engineering Qualifications

KRW Consulting, Inc. (KRW) has provided environmental engineering services to industry and local government agencies throughout the western United States since 1987. Our typical project approach is straight-forward, in that, we seek solutions that are technically feasible, timely and cost effective. We focus on providing solutions to, rather than studies of, environmental problems.

Our business plan is based on service as opposed to growth. We find it very rewarding to develop and maintain relationships of trust with our clients by providing them with hands-on personalized service. As a result of this philosophy, KRW continues to grow in a controlled manner while maintaining good quality assurance of our work products.

KRW's experience in environmental engineering projects is very diverse. Some of the major market areas in which we work include the following:

As well as planning and design KRW provides full in-house construction engineering services including surveying and construction Quality Assurance and Quality Control.

Refer to the following project descriptions for more detailed information regarding KRW personnel expertise and our past project experience.

Solid Waste Landfill Projects

Hinsdale County Landfill Closure, Lake City, Colorado

Hinsdale County requested that KRW perform an engineering economic evaluation of solid waste options for the County. We evaluated three options including incineration, landfilling in compliance with Subtitle D regulations, or transfer of waste to Gunnison or Montrose County landfills. The results of our evaluation indicated that the most cost effective waste management option was closure of the existing landfill and implementation of a transfer station operation for transport of the waste out of county. We prepared a closure plan for the landfill in compliance with the Colorado Department of Health Solid Waste Regulations. The closure plan was prepared based on field evaluation of ground and surface waters, landfill cover, site drainage, and topography. The plan was approved by the Colorado Department of Health.

Gunnison County Landfill, Gunnison, Colorado

This project involved the evaluation of the existing Gunnison County Landfill in light of the EPA Subtitle D Regulations and Colorado Solid Waste Regulations. Tasks performed include construction of an adequate groundwater monitoring system for the facility, additional characterization of the site geology and hydrogeology to allow the determination of need for a liner and leachate collection system for new landfill cells, preparation of an adequate Landfill Design Operations and Closure Plan which addresses landfill cell locations, operational sequence, drainage construction, and reclamation activities, and detailed cost analysis of landfill development and operations.

KRW also performed a land transfer environmental audit of the facility for the purpose of securing purchase of the site from Bureau of Land Management. KRW prepared a Candidate Conservation Agreement with Assurances to address endangered species issues on the site. KRW provides routine groundwater statistical analysis and reporting. KRW prepared and CDPHE approved the Design and Operations Plan for the landfill expansion, which included final cover design, grading, storm water controls, and landfill gas controls.

Rooney Landfill Recreational Facility, Jefferson County Colorado, Jefferson County

KRW prepared a Site Development Plan for a sports facility to be constructed on an abandoned landfill in Jefferson County. The 80-acre landfill was closed in 1982. The site development plan included a site characterization, a landfill cap re-design, a surface water drainage system, and a methane mitigation system. The cap was reinforced to control landfill gas and facilitate recreational use on the site. This system was constructed in 2002-03.

Broad-Acre Landfill, Pueblo, Colorado

A landfill design and operations plan for this 300 acre permitted facility was evaluated to determine adequacy relative to EPA Subtitle D regulations and to Colorado Department of Health Landfill Regulations. The site was completely redesigned by KRW to facilitate compliance with these regulations and to enhance environmental containment at the site. Critical issues in the redesign were detailed hydrogeologic exploration at the site, design of earthen and geosynthetic clay liner systems, design of leachate collection and removal systems, design of final cover systems, and design of storm water drainage systems. The new landfill design was approved by the Colorado Department of Health Hazardous Materials and Waste Management Division. KRW also provided all QAQC engineering for construction of a new landfill cell at the facility.

Front Range Landfill (formerly Environmental Recycling and Disposal Landfill), Weld County, Colorado

A permit application was prepared by KRW for a recycling facility and residuals landfill for southern Weld County to service the Colorado Front Range Urban Corridor. The site includes 460 acres of which approximately 200 is proposed for landfill construction. The facility includes a full scale recycling operation for the removal of glass, plastic, paper, cardboard, aluminum, and ferrous metals from the incoming waste stream. The landfill was designed in accordance with Colorado Department of Health Regulations and in view of the proposed EPA Subtitle D Regulations for solid waste facilities. Particular attention was given to the EPA proposed siting restrictions in design of the landfill. Specifically it was necessary to address the presence of an underground coal mine which was bounded by a Laramide Fault along one edge of the property. The undermined area was delineated and appropriate set-back from the fault and undermined area was provided in the design of the landfill.

The Landfill Design, Operations, and Closure Plan included liner and leachate control system design, operations criteria and sequence, landfill cover design, surface water drainage design, groundwater and landfill gas monitoring specifications, reclamation and closure specifications, and a Quality Assurance/Quality Control Plan for landfill construction. The permit application was recommended for approval by the Colorado Department of Health and approved by Weld County. KRW subsequently provided QAQC engineering for construction of the first landfill cell and composite lined leachate sump.

Summit County Landfill, Twin Landfill Corporation, Summit County, Colorado

An amendment was prepared by KRW in 1989 to the Operations Plan for the Summit County Landfill. The amendment was necessary due to the identification of groundwater during over-excavation of a landfill cell. The amendment consisted of evaluation of hydrogeological conditions at the site by drilling and testing of soil borings; construction, sampling, and testing of monitoring wells; and design of two fill areas in accordance with the requirements of the proposed EPA Subtitle D Regulations and Colorado Landfill Regulations.

Both fill areas were designed with clay liners and leachate collection systems which convey leachate to double lined leachate sumps. Approval of the Revised Operations Plan has been received from the Colorado Department of Health Hazardous Materials and Waste Management Division as well as the Summit County Commissioners. Landfill construction QAQC, groundwater sampling, and statistical evaluation of groundwater data are conducted by KRW on an ongoing basis.

Summit County Landfill, Summit County

KRW completed a design of the vertical and lateral expansion of this operating Colorado landfill and inclusion of composting facilities in compliance with regulatory requirements. The design was reviewed and approved by CDPHE. KRW also is the QA/QC engineer for construction of environmental containment systems at the site. Stormwater and cell construction were completed under KRW oversight. On-going statistical evaluation of groundwater monitoring data is conducted by KRW. KRW is providing on-going consulting services for design, construction QA/QC, environmental assessment, environmental monitoring, and planning for landfill operations.

Eagle County Landfill, Eagle County, Colorado

KRW developed a landfill design, operations, and closure plan in compliance with Federal Subtitle D regulations and BLM lease requirements. A hydrogeologic assessment was performed at the site to determine the location and characteristics of the uppermost groundwater and to provide information pertinent to design of the landfill environmental containment systems. This site was unusual in that naturally existing hydrocarbons are present in the shale and groundwater. Based on hydrogeologic conditions, KRW proposed an alternative liner for the site consisting of a 1-foot soil liner compacted to a hydraulic conductivity of 1 x 10-6 cm/sec.

An alternative groundwater monitoring system was also designed and implemented including reduced monitoring frequency for background and detection monitoring. A land transfer audit was completed for proposed transfer of the BLM land to Eagle County. KRW facilitated discussions between BLM, CDPHE, and Eagle County that resulted in the approved landfilling at the site during the interim between preparation, review and approval of the new landfill plan. KRW currently provides construction QAQC for phased landfill module construction, statistical analysis of groundwater sampling data, and exploratory investigation into a further expansion into newly acquired land to the east of current operations.

Phantom Landfill, Twin Landfill Corporation

KRW completed a thorough groundwater investigation and landfill design and operations plan for the proposed Phantom Landfill, Fremont County, Colorado. The landfill design and groundwater monitoring plans were approved by the Colorado Department of Public Health and Environment. Of special interest at this site is a water-bearing unit within a geologic formation which generally does not contain water (Benton Formation). The water-bearing limestone member of this formation sub-crops at the site which required careful evaluation by KRW and intense scrutiny by CDPHE.

KRW determined the source of recharge and aquifer properties for the water bearing unit and designed and constructed a groundwater monitoring plan for the landfill. KRW successfully characterized the site and defended the resulting landfill design and monitoring program to the CDPHE in accordance with Subtitle D regulations. The site was approved by Fremont County and is currently in operation with all QAQC, engineering and groundwater statistical analysis and reporting being conducted by KRW. KRW has also designed and received CDPHE approval for a solidification area and an asbestos disposal facility at the site.

Parfet Clay Pits Closure and Golf Course Development, City of Golden, Colorado

Mined out clay pits in Golden were historically used for disposal of fly-ash and miscellaneous other relatively inert wastes. KRW was retained to perform an environmental assessment of the property to include investigation of groundwater, surface water, waste sampling, historical data review, and report preparation. Based on the assessment, a closure plan was formulated and submitted to Colorado Department of Public Health and Environment under the "Voluntary Cleanup Program".

The closure plan included conceptual design for construction over the landfill of a low permeability cap that will be compatible with the planned end land use as a golf course. The design phase of the project included addressing storm water management, subsurface drainage management, slope stability, long term site monitoring, and volumetric calculations for waste relocation and earth moving operations. The Colorado Department of Public Health and Environment approved the closure plan. KRW provided construction supervision services for the cap construction and is currently monitoring cap performance for the City of Golden.

South Canyon Landfill, TADCO Disposal and City of Glenwood Springs, Colorado

KRW completed the site hydrogeologic characterization to develop a groundwater monitoring plan for this facility located near Glenwood Springs, Colorado. Additional work completed for this facility includes a QA/QC Plan for construction of site "engineered containment systems" and a closure plan for site impoundments used for the past disposal of septic wastes. KRW oversaw the design-build of a leachate remediation/collection system and leachate evaporation pond.

Milner (Routt County) Landfill, Twin Landfill Corporation

KRW completed a redesign of this operating Colorado landfill to meet with Subtitle D regulatory requirements. The redesign included an expansion of the current footprint to enable filling operation for the next 80 years. The expansion area was found to be over an abandoned coal mine at 200 feet depth, which was determined, through a cooperative assignment with a mine expert, to be not affecting the proposed overlying landfill.

As part of this project, a hydrogeologic characterization of the site was completed, which included the development of a groundwater monitoring program. To date, KRW has evaluated historic site data including groundwater quality and flow data. Four new wells have been installed to aid in characterizing the site for the development of a site monitoring program.

Meeker Landfill, Rio Blanco County, Colorado

KRW provided construction QA/QC for the construction of a 4-acre landfill cap at the old Meeker landfill. KRW is currently responsible for the post-closure inspections.

Wray Gulch and Rangely Landfills, Rio Blanco County, Colorado

KRW is providing design and construction QA/QC services for the on-going landfill construction and the planned landfill expansion. The landfill expansion plan was approved by CDPHE.

Pine Gulch Landfill, Jefferson County, Colorado

The Pine Gulch Landfill (PGL), an approximately 10-acre site, was operated by Jefferson County as a landfill and then as a transfer station between 1969 and 1978. KRW performed a site investigation of this abandoned landfill. The site investigation included surveying, methane gas monitoring, groundwater monitoring, surface water monitoring, hydraulic conductivity testing, and cap soil characterization. The site investigation included a variety of improvement options for this voluntary cap improvement. KRW designed a cap improvement plan with construction documents for this site.

Composting Facility Projects

Summit County Landfill, Summit County, Colorado

KRW designed and permitted a composting facility at the Summit County Landfill, which was constructed to operate as a Class I composting facility to accept biosolids, and non-solid feedstocks, and bulking materials. The composting facility was included in the Summit County design and operations plan and approved by CDPHE. The facility includes a lined compost pad (approx. 0.5 acre), and a run-off containment pond. Grading of the site was accomplished to prevent run-on stormwater entering the compost pad.

Milner (Routt County) Landfill, Twin Landfill Corporation

KRW designed and permitted a composting facility at the Milner Landfill, which was constructed to operate as a Class I composting facility to accept biosolids, and non-solid feedstocks, and bulking materials. The composting facility was included in the Milner Landfill design and operations plan and approved by CDPHE. The facility includes a lined compost pad (approx. 2 acres), and a run-off containment pond. Grading of the site was accomplished to prevent run-on stormwater entering the compost pad.

Solid Waste Transfer Stations

Union Avenue Transfer Station, Denver Waste Transfer, Sheridan, Colorado

KRW completed the Site Development Plan for the permitting of a 3000 ton per day capacity transfer station constructed on an abandoned landfill in Sheridan, Colorado. The Plan includes the Transfer Station Design and Operations Plan. The Plan was accepted by the CDPHE and the City of Sheridan and a permit was granted in 1999.

North Washington Waste Transfer Station, Colorado Waste Systems, Adams Co., Colorado

KRW completed the Site Development Plan for the permitting of a 4000 ton per day capacity transfer station constructed on an abandoned landfill in Adams County, Colorado. The Plan includes the Transfer Station Design and Operations Plan. The facility was granted an operating permit in 2000.

Douglas County Waste Transfer Station, Colorado Waste Services, Douglas Co., Colorado

KRW completed the Site Development Plan for the permitting of a 3000 ton per day capacity transfer station constructed adjacent to an environmentally sensitive wetlands area in Douglas County, Colorado. The Plan includes the Transfer Station Design and Operations Plan. Permit review is currently in progress for this facility.

Stormwater Management Projects

Jefferson County Aggregate Mine, Conifer, Colorado

Ground and surface water discharge from the mine flow into an intermittent stream. KRW was responsible for surface water sampling and data evaluation, preparation of drainage and sedimentation specifications, and preparation of a National Pollution Discharge Elimination System (NPDES) permit application for the site.

Clear Creek Asphalt Plant, Jefferson County, Colorado

A storm water permit and storm water management plan were prepared by KRW to address the control of sediments and potential organic chemicals used in operations at this site. The work included sampling of process and storm water discharges, development of an ongoing sampling and inspection program, and engineering recommendations for process water and storm water management. KRW is responsible for routine monitoring at the site.

Twin Landfill Corporation Stormwater Permits

KRW was responsible for preparing storm water permit applications for Milner and Phantom Landfills operated by Twin Landfill Corporation. Storm water management plans have also been prepared and implemented for these facilities. KRW is responsible for routine maintenance of these permits.

Front Range Landfill, Sanifill, Inc., Weld County, Colorado

KRW prepared a construction storm water management plan and permit and a landfill operations storm water plan and permit for this landfill located near Erie, Colorado.

Mid-American Waste Systems of Colorado, Inc. Storm water Permits

KRW was responsible for preparing storm water permit applications for Broad-Acre Landfill formerly owned by Mid-American. Storm water management plans were also prepared for these facilities.

South Canyon Landfill, City of Glenwood Springs, Colorado

KRW prepared a construction storm water management plan and permit and a landfill operations storm water plan and permit for this landfill located near Glenwood Springs, Colorado. KRW is responsible for routine maintenance of these permits.

North Washington Waste Transfer Station, Colorado Waste Systems, Adams Co., Colorado

KRW completed the application for a Flood Plain Use Permit. The Flood Plain Use permit was granted by Adams County.

Construction Administration / Quality Control and Quality Assurance

BroadAcre Landfill, Pueblo, Colorado

KRW provided all QAQC engineering for construction of a new landfill cell at the facility. KRW prepared a construction certification report that was approved by CDPHE. The estimated value of the construction was $1M.

Front Range Landfill (formerly Environmental Recycling and Disposal Landfill), Weld County, Colorado

KRW provided QAQC engineering for construction of the first landfill cell and composite lined leachate sump. KRW prepared a construction certification report that was accepted by CDPHE. The estimated value of the construction was $0.75M.

Summit County Landfill, Twin Landfill Corporation, Summit County, Colorado

KRW is providing construction administration and on-going quality control/quality assurance engineering services to Summit County for the construction of the 400-acre landfill expansion. Services include bid document preparation, bid evaluation, construction oversight and inspection, and surveying. KRW will prepare a QA/QC report for the CDPHE to certify the landfill construction. The estimated value of the construction is $2.0M.

Phantom Landfill, Twin Landfill Corporation

KRW provided construction administration and quality control/quality assurance engineering services to Twin Landfill Corporation for the construction of the first two cells and the solidification basin at Phantom Landfill in Fremont County, Colorado. Services included bid document preparation, bid evaluation, construction oversight and inspection, and surveying. KRW prepared QA/QC reports for the CDPHE to certify the landfill construction. The estimated value of the construction was $1.0M.

Eagle County Landfill, Eagle County, Colorado

KRW provided construction administration and quality control/quality assurance engineering services to Eagle County for the construction of eight landfill modules and the solidification basin at Eagle County Landfill in Eagle County, Colorado. Services included construction oversight and inspection, and surveying. KRW prepared QA/QC reports and final certification reports for each module for presentation the CDPHE to approve the landfill module construction. Approval was granted for each module. Construction was performed by Eagle County personnel.

Milner Landfill, Twin Landfill Corporation, Milner, Colorado

KRW provided construction administration and quality control/quality assurance engineering services to TWIN for the construction of landfill module one at the Milner Landfill in Routt County, Colorado. Services included construction oversight and inspection, and surveying. KRW prepared QA/QC reports and final certification reports for the construction of module one for presentation the CDPHE to approve the landfill module construction. Approval was granted for each module. Construction was performed by TWIN personnel. KRW continues to provide engineering services to TWIN during subsequent landfill module construction.

Parfet Clay Pits Closure and Golf Course Development, City of Golden, Colorado

KRW is providing construction administration and on-going quality control/quality assurance engineering services to the City of Golden for the construction of a landfill cap on the Parfet Clay Pits. Services include bid document preparation, bid evaluation, construction oversight and inspection, and surveying. KRW will prepare a QA/QC report for the CDPHE to certify the landfill cap construction. The estimated value of the construction is $1.6M.

South Canyon Landfill, TADCO Disposal and City of Glenwood Springs, Colorado

KRW oversaw the design-build of a leachate remediation/collection system and leachate evaporation pond. The estimated value of the construction was $1.0M.

Meeker Landfill, Rio Blanco County, Colorado

KRW provided construction QA/QC for the construction of a 4-acre landfill cap at the old Meeker landfill. KRW is currently responsible for the post-closure inspections.

Wray Gulch and West Rangely Landfills, Rio Blanco County, Colorado

KRW is providing design and construction QA/QC services for the on-going landfill construction and the planned landfill expansion.

Statistical evaluation of monitoring data

AquaStat is an environmental statistics computer program developed by KRW. Many commercially available statistics programs are "black box" programs resulting in answers that may not be defensible or understandable. However, in developing AquaStat we gained a much fuller understanding of the implications of the answers provided by the various statistical tests used.

AquaStat is based on the methods described by Gibbons (1994), Gilbert (1987), Hollander (1973) and EPA (1989 and 1992). The program operates as a plug-in to Microsoft ExcelŽ. The program allows normality testing and data transformations for normalization, outlier testing and labeling, seasonality adjustments, censored data handling, trend analyses, and control chart creation. It also allows conventional view of environmental data in a spreadsheet or chart with all the functionality of ExcelŽ.

Data is evaluated for outliers (where suspected) using Dixon's method as described by Gibbons (Gibbons, 1994). The data is evaluated for normality using the Shapiro-Wilk test as described by Gibbons (Gibbons, 1994). Where a transformation (i.e., square, square root, logarithmic) allowed normalization of data that do not follow a standard normality distribution, all statistical tests are then conducted on transformed data. Therefore, the reported mean and standard deviation are calculated, and the control charts are constructed, based on transformed data where a transformation is noted.

For example, statistical comparisons are conducted using Shewart-CUSUM control charts for each of the parameters listed in the below listed table for each monitoring well. Shewart-CUSUM charts include two control limits. The "scl" limit is the lower of the two limits and represents a target maximum for the cumulative sum (CUSUM) calculation of the data. The CUSUM is a measurement of trend in the data. The "h" limit represents the target maximum for any individual sample result. Our selected "k", "scl", and "h" values for the Shewart-CUSUM chart construction are more conservative than allowed by EPA thereby increasing the power of the statistical test to provide early detection of landfill impact.

A control limit exceedance exhibited by a parameter is accepted (statistical evidence of groundwater impact is assumed) if verification sampling in the following quarter confirms the exceedance. If the verification sample does not confirm the exceedance, the exceedance is labeled as an outlier. One exception to this general procedure is the case where an ongoing upward trend is statistically significant and the exceedance is a result of that trend. In this case, the exceedance will not be labeled as an outlier.

Table - Minimum List of Parameters Analyzed Using Shewart-CUSUM Control Charts*

Alkalinity as CaCO3, Potassium (K)
Chloride (Cl) Sodium (Na)
Sulfate (SO4) Total Organic Carbon (TOC)
Nitrate/Nitrite-N (NO3/NO2-N) Conductivity
Calcium (Ca) pH
Magnesium (Mg) Total Dissolved Solids (TDS)
*Metals were also analyzed where sufficient detections were available in the background set.

Shewart-CUSUM control charts are also constructed for metals for wells where the detection rate for these parameters was, for example, greater than 25 percent. The normality assumptions are violated in construction of the control charts when the percentage of non-detects is greater than 50%; nevertheless, the charts are useful in showing data trends. Water level (WL) time series charts are also constructed for visual depiction of fluctuations in the groundwater table.

Projects where the AquaStat has been utilized include the Eagle County Landfill, Milner Landfill, Phantom Landfill, Gunnison County Landfill, Summit County Landfill, and the Fossil Trace Golf Course.

With each of these projects, KRW was intimately involved with the client personnel, project decisions, and the associated regulatory agencies.
Engineering Client Reference List
Land Surveying Qualifications
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