DSHW-2024-006151

Engineering & Geosciences
14425 S. Center Point Way, Bluffdale, Utah 84065 ~ T: [phone] ~ F: [phone]

MEMORANDUM

To: Utah Division of Waste Management and Radiation Control
From: Mike Vorkink P.G., Jon Peaden
Date: May 3, 2024
Subject: Comments on Proposed Rules for Class VII Facility

GeoStrata has reviewed the draft rules that the Division of Waste Management and Radiation
Control (DWMRC) has proposed for a Class VII Landfilling facility and Surface Impoundments
found in R315-321 and R315-322. It is our understanding that the disposal facilities permitted
under the Utah Division of Oil Gas and Mining (DOGM) with ponds will be regulated by the
DWMRC. It is also understood that a Class VII facility may have a landfill permitted that will take
Exploration and Production Waste and R315-321 is specific for the landfilling requirements.
R315-322 is intended for regulation of Surface Impoundments are to be used for liquid waste such
as production water. The following are comments on specific rules that are within the proposed
class of landfill.

Comment 1. Proposed rule R315-322-5 (10)(b) says:

“(b) The owner or operator of a new solid waste surface impoundment or lateral
expansion of an existing solid waste surface impoundment shall either:

(i) meet the groundwater alternative or waiver found in Subsection R315-
302-1(2)(e)(vi)7;

(ii) monitor the groundwater beneath the impoundment as specified in Rule
R315-30824; or

(iii) install and maintain leak detection equipment and conduct monitoring
according to Section R315-322-5(12).

Due to the liquid nature of the waste and the potential that liquids will accumulate
in the impoundment it is possible that liquids could be found in the subsurface if
the liners are compromised. If an exemption is approved in part (i) at the time of
permitting and no monitoring is required a leak will not be detected unless a leak
detection system is in place or down gradient wells intercept liquid from the leak.
Having a waiver does not make sense if there is no means to identify a leak in the
future.

At a minimum, this rule should call for a leak detection system of each
impoundment if waiver is granted. We would like to see the DWMRC have a more
conservative approach to the protection of groundwater and prevent a
contamination plume of impoundment leachate in the event of a compromised liner.
It may be more appropriate to require all impoundments have downgradient
monitoring wells constructed in a way to identify problems with the liner and not
allow exemption of groundwater monitoring.

Comment 2. Proposed rule R315-322-5 (10)(i) and (12) has guidance on the use of a Leak
Detection System. It is in GeoStrata’s experience that leak detection systems are
not a reliable measure of problems with liner systems. Problems with leak detection
systems have often been remedied by construction of monitoring wells
downgradient from the impoundment. We would not recommend that leak
detections system be the only means to identifying problems with the liner or in
place of a groundwater monitoring system.
Ponds and impoundments that have HDEP lining systems that meet industry
construction standards will still have leaks. Other regulatory agencies have used
allowable leakage rates for HDPE liners to help identify problems with liners. Will
the DWMRC have an allowable leakage rate to delineate when corrective actions
will need to be taken?
The rule does not mention that the construction of the collection system for leak
detection system should include an electrically conductive geofabric or similar
material between synthetic liners to allow for a liner integrity survey.

Most of the existing evaporation ponds in the Uinta Basin were constructed with a
primary 60 ml liner and a natural clay secondary liner. The primary and secondary
liners in cells constructed in this manner are not sealed together and can have
groundwater water between the liners in areas of shallow groundwater. As a result,
differentiating the source of water in a leak detection system can be difficult. What
guidance can the DWMRC provide for impoundments that have this type of
construction?

Comment 3. In the proposed rule for Standards for Design R315-322-5 (1) it states:

“(1) Surface impoundments shall be designed for 55 acre-feet of water or less,
unless otherwise approved by the director.”

The statement at the end “unless otherwise approved by the director” leaves the rule
to be open for wide interpretation and has potential for unlimited size of a surface
impoundment without the indication of how size of impoundment should be
limited. Phrases of this type through the proposed rules and existing rules should

be carefully evaluated and have limitations if the director will allow for exceptions
to a rule. It is also unclear whether this rule applies to only liquid waste. Further
clarification on the size of an impoundment would be helpful for applicants.

Comment 4. In the proposed rule for Standards of Operation R315-322-6 (4)(a) it states:

“(a) Hydrocarbon accumulation, other than de minimis quantities, on a Class VII
solid waste surface impoundment is prohibited. Any such accumulation shall be
removed within 24 hours of the time accumulation began.”
In order to make sure that operators and regulators have the same expectation, a
clearer definition should be considered.

Comment 5. In the proposed rule for Standards of Operation R315-322-6 (5) it states:

“(5) Overspray including foam, from sprinklers, wind, or enhanced evaporation
systems, outside of lined areas shall be corrected and cleaned up immediately.”
The Utah Division of Oil Gas and Mining (DOGM) currently limits wind speed
during usage of enhanced evaporations systems. Will there be any wind speed
restrictions for using enhanced evaporation systems?
Comment 6. The E&P waste disposal operations that have been regulated by DOGM had some
regulation on several other items that are not included in the proposed rules.
DWMRC will need to provide some guidance and regulatory oversight on the
following items:
• Will netting be required for skim ponds? If so, what netting requirements
will apply to skim ponds?
• Can operators of a Class VII landfill remove waste from the landfill and if
so, what are the cleanup standards? Can solid precipitates and other solids
that accumulate in the surface impoundments be removed and placed in a
landfill?
• What analytes are to be tested when testing background soils?
• Will facilities with existing DWMRC permits need permit mods or new
permits if they want to convert an existing DOGM permitted pond to a
surface impoundment? What will be required if they want to convert the
pond to a Class VII landfill?
• How do operators reconcile differences in design standards between EPA
and DWMRC? Who has primacy?
• Many facilities have landfarms that were permitted with DOGM. The
DWMRC has stated that landfarms can be reclaimed by covering them in
soil or clay. Is any post closure monitoring required in this process?
• Is any soil testing required of both the material in the landfarm and or the
soil cap before closure?

• Can water from the landfill be transferred into surface impoundments?
• There is no guidance for off-loading, mixing bins or areas that will be used
for stabilizing the waste that is outside the landfill cell. What containment
will be acceptable for mixing waste to stabilize highly liquid waste? Will
these areas need to be lined or constructed with berms to contain spills?
• Can high liquid waste be solidified inside an operating landfill cell? If so,
what limitations will be put in place to protect the liner and operators?