DSHW-2018-003183 - 0901a068807e72e5

State of Utah
GARY R. HERBERT
Governor
SPENCERJ. COX
Lieutenant Governor
Department of
Environmental Quality
Alan Matheson
Execative Director
DTVISION OF WASTE MANAGEMENT
AND RADIATION CONTROL
Scott T. Anderson
Director
April 11,2018
Scott Sensanbaugher, Director
Department of Public Works
American Fork City
275 East 200 North
American Fork. Utah 84003
RE:Request for Decision on Management of the Tibble Fork Dam Sediment
Dear Mr. Sensanbaugher:
On January 31,2018, the Division of Waste Management and Radiation Control sent you a letter
(enclosed) outlining options for management of sediment from the Tibble Fork Dam. To date, we have
not received your decision on which management option you have chosen.
Please submit to this office by April 30, 2018, American Fork City's decision on the management of this
sediment from the irrigation water basins.
If you have any questions, please call Ed Costomiris or Eric Baiden at [phone].
Sincerely,
Scott T. Anderson, Director
Division of Waste Management and Radiation Control
(Over)
195 North 1950 West'Salt Lake City, UT
Mailing Address: P.O. Box 144880'Salt Lake City, UT 84114-4880
Telephone [phone]. Fax [phone] 'T.D.D. (801) 5364284
www.deq.utah'goa
Printed on 100% recYcled PaPer
DSHW-2018-003183
STA/DSN/KI
Enclosure: January 3l,20l8l,etter(DSHW-2018-000744)
c: Ralph Clegg, EHS, MPA, Health Officer, Utah County Health Department
Bryce C. Larsen, MPA, LEHS, Environmental Health Director, Utatr County Health Department
Brad Frost, Mayor of American Fork City (Email)
Alan Jenkins, NUCWCD
JohnJacobs, NUCWCD
State of Utah
GARY R. HERBERT
Governor
SPENCERJ. COX
Lieulenant Governor
Department of
Environmental Quality
Alan Matheson
Executive Drector
DryISION OF WASTE MANAGEMENT
AND RADTATION CONTROL
Scott T. Anderson
Director
January 31,2018
Scott Sensanbaugher, Director
Department of Public Works
American Fork City
275 East 200 North
American Fork, UT 84003
RE: Management of the Tibble Fork Dam Sediment from Irrigation Water Basins
Dear Mr. Sensanbaugher:
The Division of Waste Management and Radiation Control has completed its review of the Tibble Fork
Dam Sediment Release - Comprehensive Monitoring Plan Interim and Year-End Data Report which
was prepared by the North Utah County Water Conservancy District.
In addition to other information, the Report contains analytical results of samples taken from the
American Fork City and Highland City's inigation sediment basins. Data pertaining to the sediment is
presented in Tables 8,9 and l0 of the Report. Table 9 shows the calculated toxicity characteristic
ieaching procedure (TCLP) metals results, which are based on the total metals results found in Table 8
divideilby the TCLP dilution factor of 20,to determine if the TCLP concentrations would be exceeded.
This dilution is part of the toxicity characteristic leaching procedure. The calculated values are
conservative because not all metals are present in a sample leach.
The only metal to exceed the toxicity regulatory level in Table 9 was lead. Based on the calculated
value, the lead concentrations in Table 9 ranged from 5.35 mg/l to 9.5 mgll, which exceeds the
regulatory level of 5.0 mg/I. Consequently, the actual leachability of the lead was determined by
p"ifot-ing the TCLP on two composite samples, one from each irrigation sediment basin. The
compositasamples were prepared by the contract laboratory from the individual samples listed in Table
8. The TCLP results in Table 10 show that the leachable lead in both samples to be 0.15 mg/l or less.
Therefore, the sediment in the inigation basins are not hazardous waste as defined in R3l5-26l-24 of
the Utah Administrative Code.
195 North 1950 West. Salt Lake City, UT
Mailing Address: P.O. Box 144880 . Salt Lake City, UT 84114-4880
Telephone [phone] . Fax [phone] 'T.D.D. (801) 5364284
tuuxo.ileq.utah.gozt
Printed on 100% recYcled PaPer
DSHW-20 r 8-000744
Although the sediment found in the two inigation basins is not hazardous waste, it is a solid waste and
must be managed appropriately. Based on the Report, the constituent of concem for management is
arsenic, with total concentration values ranging from 19.5 to 27.2 mg/kg-dry. The Regional Screening
Levels' established by the EPA for arsenic in residential and industrial soil applications are 0.68 mg/kg
and 3.0 mg/kg respectively. Due to the elevated levels of arsenic, the Division has determined that there
are three options for managing the sediment from the inigation basins.
Option I - Transport the Sediment to a Lined Solid Waste Landfill
Authorization would need to be obtained from the landfill manager, or his designee, prior to shipping the
sediment for placement in an HDPE-lined landfill. The City would need to keep coples of the rttipping
papers for a period of five years documenting each shipment.
The City, or its consultant, would need to submit a sampling and analysis plan (SAp) to the Director forreview and approval. The SAP needs to be developed in order to determine background concentrations
at each public works site where the City would like to place the sediment. Following approval by the
Director, the City, or its consultant, would conduct the sampling and analysis specifiied-in ttre approvedSAP. Based on the analytical results, one of two management options would b-e available.
a. "Option 2A" would apply if the arsenic concentrations of the sediment are less than the
surrounding material at the public works location. If this is demonstrated analytically, the
sediment can be placed at this location without further requirements.
b. "Option 28" would apply if the arsenic concentration of the sediment exceeds that of the
background value foun-d at the public works location. If the analytical results are within therange of acceptable risk", as defined in the Regional Screening Level document, the sediment
could be used as fill provided the City complete the following two requirements for each public
works location that meets the criteria of Option 28.
l. A Soil Management Plan (SMP) would need to be prepared and submitted to the Director forreview and approval for each public works site used for the placement of sediment.
2. An Environmental Covenant would need to be filed with the County Recorder,s Office for
each site which received sediment that had higher concentrations of arsenic than the
background value of the public works location.
This option would require American Fork City or its consultant, to submit a SAP to the Director forreview and approval to determine background concentrations. Once approved, the sampling andanalysis would be conducted according to the plan. If the background-arsenic concentratio^ u." higherthan the concentration of the sediment, the sediment can be placed in that specific area. If the arseniclevels of the sediment exceed those of the background concentrations, the sediment must be managed asspecified in Options I or 2 above.
Please notify the Division of the sediment management option that the American Fork City has chosen
to implement. If you have any questions, please call Ed Costomiris at [phone].
Sincerelv.
Division of Waste Management and Radiation Control
STA/EGC/KI
c: Ralph Clegg, EHS, MPA, Health Officer, Utah County Health Department
Bryce C. Larsen, MPA, LEHS, Environmental Health Director, Utah County Health Department
John Jacobs. NUCWCD
Alan Jenkins, NUCWCD
'The Regional Screening Levels tables provide comparison values for residential and
commercial/industrial exposures to soil, air, and tap water (drinking water).
ii The acceptable risk is defined as the cancer risk between the range of one in l0-a through one in 10-6.
T. Anderson. Director